Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * scsi_lib.c Copyright (C) 1999 Eric Youngdale |
| 3 | * |
| 4 | * SCSI queueing library. |
| 5 | * Initial versions: Eric Youngdale (eric@andante.org). |
| 6 | * Based upon conversations with large numbers |
| 7 | * of people at Linux Expo. |
| 8 | */ |
| 9 | |
| 10 | #include <linux/bio.h> |
James Bottomley | d3f46f3 | 2008-01-15 11:11:46 -0600 | [diff] [blame] | 11 | #include <linux/bitops.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <linux/blkdev.h> |
| 13 | #include <linux/completion.h> |
| 14 | #include <linux/kernel.h> |
| 15 | #include <linux/mempool.h> |
| 16 | #include <linux/slab.h> |
| 17 | #include <linux/init.h> |
| 18 | #include <linux/pci.h> |
| 19 | #include <linux/delay.h> |
James Bottomley | faead26 | 2006-02-14 10:42:07 -0600 | [diff] [blame] | 20 | #include <linux/hardirq.h> |
Jens Axboe | c6132da | 2007-10-16 11:08:49 +0200 | [diff] [blame] | 21 | #include <linux/scatterlist.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | |
| 23 | #include <scsi/scsi.h> |
Christoph Hellwig | beb4048 | 2006-06-10 18:01:03 +0200 | [diff] [blame] | 24 | #include <scsi/scsi_cmnd.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | #include <scsi/scsi_dbg.h> |
| 26 | #include <scsi/scsi_device.h> |
| 27 | #include <scsi/scsi_driver.h> |
| 28 | #include <scsi/scsi_eh.h> |
| 29 | #include <scsi/scsi_host.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | |
| 31 | #include "scsi_priv.h" |
| 32 | #include "scsi_logging.h" |
| 33 | |
| 34 | |
Tobias Klauser | 6391a11 | 2006-06-08 22:23:48 -0700 | [diff] [blame] | 35 | #define SG_MEMPOOL_NR ARRAY_SIZE(scsi_sg_pools) |
Jens Axboe | 5972511 | 2007-04-02 10:06:42 +0200 | [diff] [blame] | 36 | #define SG_MEMPOOL_SIZE 2 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | |
| 38 | struct scsi_host_sg_pool { |
| 39 | size_t size; |
Jens Axboe | a8474ce | 2007-08-07 09:02:51 +0200 | [diff] [blame] | 40 | char *name; |
Christoph Lameter | e18b890 | 2006-12-06 20:33:20 -0800 | [diff] [blame] | 41 | struct kmem_cache *slab; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | mempool_t *pool; |
| 43 | }; |
| 44 | |
James Bottomley | d3f46f3 | 2008-01-15 11:11:46 -0600 | [diff] [blame] | 45 | #define SP(x) { x, "sgpool-" __stringify(x) } |
| 46 | #if (SCSI_MAX_SG_SEGMENTS < 32) |
| 47 | #error SCSI_MAX_SG_SEGMENTS is too small (must be 32 or greater) |
| 48 | #endif |
Adrian Bunk | 52c1da3 | 2005-06-23 22:05:33 -0700 | [diff] [blame] | 49 | static struct scsi_host_sg_pool scsi_sg_pools[] = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | SP(8), |
| 51 | SP(16), |
FUJITA Tomonori | fd820f4 | 2007-09-18 12:14:37 +0200 | [diff] [blame] | 52 | #if (SCSI_MAX_SG_SEGMENTS > 32) |
James Bottomley | d3f46f3 | 2008-01-15 11:11:46 -0600 | [diff] [blame] | 53 | SP(32), |
FUJITA Tomonori | fd820f4 | 2007-09-18 12:14:37 +0200 | [diff] [blame] | 54 | #if (SCSI_MAX_SG_SEGMENTS > 64) |
James Bottomley | d3f46f3 | 2008-01-15 11:11:46 -0600 | [diff] [blame] | 55 | SP(64), |
| 56 | #if (SCSI_MAX_SG_SEGMENTS > 128) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | SP(128), |
James Bottomley | d3f46f3 | 2008-01-15 11:11:46 -0600 | [diff] [blame] | 58 | #if (SCSI_MAX_SG_SEGMENTS > 256) |
| 59 | #error SCSI_MAX_SG_SEGMENTS is too large (256 MAX) |
FUJITA Tomonori | fd820f4 | 2007-09-18 12:14:37 +0200 | [diff] [blame] | 60 | #endif |
| 61 | #endif |
| 62 | #endif |
James Bottomley | d3f46f3 | 2008-01-15 11:11:46 -0600 | [diff] [blame] | 63 | #endif |
| 64 | SP(SCSI_MAX_SG_SEGMENTS) |
Jens Axboe | a8474ce | 2007-08-07 09:02:51 +0200 | [diff] [blame] | 65 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 66 | #undef SP |
| 67 | |
Martin K. Petersen | 7027ad7 | 2008-07-17 17:08:48 -0400 | [diff] [blame] | 68 | struct kmem_cache *scsi_sdb_cache; |
Boaz Harrosh | 6f9a35e | 2007-12-13 13:50:53 +0200 | [diff] [blame] | 69 | |
Tejun Heo | a1bf9d1d | 2005-04-24 02:08:52 -0500 | [diff] [blame] | 70 | static void scsi_run_queue(struct request_queue *q); |
James Bottomley | e91442b | 2005-09-09 10:44:16 -0500 | [diff] [blame] | 71 | |
| 72 | /* |
| 73 | * Function: scsi_unprep_request() |
| 74 | * |
| 75 | * Purpose: Remove all preparation done for a request, including its |
| 76 | * associated scsi_cmnd, so that it can be requeued. |
| 77 | * |
| 78 | * Arguments: req - request to unprepare |
| 79 | * |
| 80 | * Lock status: Assumed that no locks are held upon entry. |
| 81 | * |
| 82 | * Returns: Nothing. |
| 83 | */ |
| 84 | static void scsi_unprep_request(struct request *req) |
| 85 | { |
| 86 | struct scsi_cmnd *cmd = req->special; |
| 87 | |
James Bottomley | 28018c2 | 2010-07-01 19:49:17 +0900 | [diff] [blame] | 88 | blk_unprep_request(req); |
Christoph Hellwig | beb4048 | 2006-06-10 18:01:03 +0200 | [diff] [blame] | 89 | req->special = NULL; |
James Bottomley | e91442b | 2005-09-09 10:44:16 -0500 | [diff] [blame] | 90 | |
James Bottomley | e91442b | 2005-09-09 10:44:16 -0500 | [diff] [blame] | 91 | scsi_put_command(cmd); |
| 92 | } |
Tejun Heo | a1bf9d1d | 2005-04-24 02:08:52 -0500 | [diff] [blame] | 93 | |
James Bottomley | 4f5299a | 2009-01-02 10:42:21 -0600 | [diff] [blame] | 94 | /** |
| 95 | * __scsi_queue_insert - private queue insertion |
| 96 | * @cmd: The SCSI command being requeued |
| 97 | * @reason: The reason for the requeue |
| 98 | * @unbusy: Whether the queue should be unbusied |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 99 | * |
James Bottomley | 4f5299a | 2009-01-02 10:42:21 -0600 | [diff] [blame] | 100 | * This is a private queue insertion. The public interface |
| 101 | * scsi_queue_insert() always assumes the queue should be unbusied |
| 102 | * because it's always called before the completion. This function is |
| 103 | * for a requeue after completion, which should only occur in this |
| 104 | * file. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 105 | */ |
James Bottomley | 4f5299a | 2009-01-02 10:42:21 -0600 | [diff] [blame] | 106 | static int __scsi_queue_insert(struct scsi_cmnd *cmd, int reason, int unbusy) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | { |
| 108 | struct Scsi_Host *host = cmd->device->host; |
| 109 | struct scsi_device *device = cmd->device; |
Mike Christie | f0c0a37 | 2008-08-17 15:24:38 -0500 | [diff] [blame] | 110 | struct scsi_target *starget = scsi_target(device); |
Tejun Heo | a1bf9d1d | 2005-04-24 02:08:52 -0500 | [diff] [blame] | 111 | struct request_queue *q = device->request_queue; |
| 112 | unsigned long flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 113 | |
| 114 | SCSI_LOG_MLQUEUE(1, |
| 115 | printk("Inserting command %p into mlqueue\n", cmd)); |
| 116 | |
| 117 | /* |
Tejun Heo | d8c37e7 | 2005-05-14 00:46:08 +0900 | [diff] [blame] | 118 | * Set the appropriate busy bit for the device/host. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | * |
| 120 | * If the host/device isn't busy, assume that something actually |
| 121 | * completed, and that we should be able to queue a command now. |
| 122 | * |
| 123 | * Note that the prior mid-layer assumption that any host could |
| 124 | * always queue at least one command is now broken. The mid-layer |
| 125 | * will implement a user specifiable stall (see |
| 126 | * scsi_host.max_host_blocked and scsi_device.max_device_blocked) |
| 127 | * if a command is requeued with no other commands outstanding |
| 128 | * either for the device or for the host. |
| 129 | */ |
Mike Christie | f0c0a37 | 2008-08-17 15:24:38 -0500 | [diff] [blame] | 130 | switch (reason) { |
| 131 | case SCSI_MLQUEUE_HOST_BUSY: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | host->host_blocked = host->max_host_blocked; |
Mike Christie | f0c0a37 | 2008-08-17 15:24:38 -0500 | [diff] [blame] | 133 | break; |
| 134 | case SCSI_MLQUEUE_DEVICE_BUSY: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 135 | device->device_blocked = device->max_device_blocked; |
Mike Christie | f0c0a37 | 2008-08-17 15:24:38 -0500 | [diff] [blame] | 136 | break; |
| 137 | case SCSI_MLQUEUE_TARGET_BUSY: |
| 138 | starget->target_blocked = starget->max_target_blocked; |
| 139 | break; |
| 140 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 141 | |
| 142 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 143 | * Decrement the counters, since these commands are no longer |
| 144 | * active on the host/device. |
| 145 | */ |
James Bottomley | 4f5299a | 2009-01-02 10:42:21 -0600 | [diff] [blame] | 146 | if (unbusy) |
| 147 | scsi_device_unbusy(device); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 148 | |
| 149 | /* |
Tejun Heo | a1bf9d1d | 2005-04-24 02:08:52 -0500 | [diff] [blame] | 150 | * Requeue this command. It will go before all other commands |
| 151 | * that are already in the queue. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | * |
| 153 | * NOTE: there is magic here about the way the queue is plugged if |
| 154 | * we have no outstanding commands. |
| 155 | * |
Tejun Heo | a1bf9d1d | 2005-04-24 02:08:52 -0500 | [diff] [blame] | 156 | * Although we *don't* plug the queue, we call the request |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 157 | * function. The SCSI request function detects the blocked condition |
| 158 | * and plugs the queue appropriately. |
Tejun Heo | a1bf9d1d | 2005-04-24 02:08:52 -0500 | [diff] [blame] | 159 | */ |
| 160 | spin_lock_irqsave(q->queue_lock, flags); |
James Bottomley | 59897da | 2005-09-14 12:57:42 -0400 | [diff] [blame] | 161 | blk_requeue_request(q, cmd->request); |
Tejun Heo | a1bf9d1d | 2005-04-24 02:08:52 -0500 | [diff] [blame] | 162 | spin_unlock_irqrestore(q->queue_lock, flags); |
| 163 | |
| 164 | scsi_run_queue(q); |
| 165 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 166 | return 0; |
| 167 | } |
| 168 | |
James Bottomley | 4f5299a | 2009-01-02 10:42:21 -0600 | [diff] [blame] | 169 | /* |
| 170 | * Function: scsi_queue_insert() |
| 171 | * |
| 172 | * Purpose: Insert a command in the midlevel queue. |
| 173 | * |
| 174 | * Arguments: cmd - command that we are adding to queue. |
| 175 | * reason - why we are inserting command to queue. |
| 176 | * |
| 177 | * Lock status: Assumed that lock is not held upon entry. |
| 178 | * |
| 179 | * Returns: Nothing. |
| 180 | * |
| 181 | * Notes: We do this for one of two cases. Either the host is busy |
| 182 | * and it cannot accept any more commands for the time being, |
| 183 | * or the device returned QUEUE_FULL and can accept no more |
| 184 | * commands. |
| 185 | * Notes: This could be called either from an interrupt context or a |
| 186 | * normal process context. |
| 187 | */ |
| 188 | int scsi_queue_insert(struct scsi_cmnd *cmd, int reason) |
| 189 | { |
| 190 | return __scsi_queue_insert(cmd, reason, 1); |
| 191 | } |
James Bottomley | 3921603 | 2005-06-15 18:48:29 -0500 | [diff] [blame] | 192 | /** |
James Bottomley | 33aa687 | 2005-08-28 11:31:14 -0500 | [diff] [blame] | 193 | * scsi_execute - insert request and wait for the result |
James Bottomley | 3921603 | 2005-06-15 18:48:29 -0500 | [diff] [blame] | 194 | * @sdev: scsi device |
| 195 | * @cmd: scsi command |
| 196 | * @data_direction: data direction |
| 197 | * @buffer: data buffer |
| 198 | * @bufflen: len of buffer |
| 199 | * @sense: optional sense buffer |
| 200 | * @timeout: request timeout in seconds |
| 201 | * @retries: number of times to retry request |
James Bottomley | 33aa687 | 2005-08-28 11:31:14 -0500 | [diff] [blame] | 202 | * @flags: or into request flags; |
FUJITA Tomonori | f4f4e47 | 2008-12-04 14:24:39 +0900 | [diff] [blame] | 203 | * @resid: optional residual length |
James Bottomley | 3921603 | 2005-06-15 18:48:29 -0500 | [diff] [blame] | 204 | * |
Michael Opdenacker | 59c5159 | 2007-05-09 08:57:56 +0200 | [diff] [blame] | 205 | * returns the req->errors value which is the scsi_cmnd result |
James Bottomley | ea73a9f | 2005-08-28 11:33:52 -0500 | [diff] [blame] | 206 | * field. |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 207 | */ |
James Bottomley | 33aa687 | 2005-08-28 11:31:14 -0500 | [diff] [blame] | 208 | int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd, |
| 209 | int data_direction, void *buffer, unsigned bufflen, |
FUJITA Tomonori | f4f4e47 | 2008-12-04 14:24:39 +0900 | [diff] [blame] | 210 | unsigned char *sense, int timeout, int retries, int flags, |
| 211 | int *resid) |
James Bottomley | 3921603 | 2005-06-15 18:48:29 -0500 | [diff] [blame] | 212 | { |
| 213 | struct request *req; |
| 214 | int write = (data_direction == DMA_TO_DEVICE); |
| 215 | int ret = DRIVER_ERROR << 24; |
| 216 | |
| 217 | req = blk_get_request(sdev->request_queue, write, __GFP_WAIT); |
| 218 | |
| 219 | if (bufflen && blk_rq_map_kern(sdev->request_queue, req, |
| 220 | buffer, bufflen, __GFP_WAIT)) |
| 221 | goto out; |
| 222 | |
| 223 | req->cmd_len = COMMAND_SIZE(cmd[0]); |
| 224 | memcpy(req->cmd, cmd, req->cmd_len); |
| 225 | req->sense = sense; |
| 226 | req->sense_len = 0; |
Mike Christie | 17e01f2 | 2005-11-11 05:31:37 -0600 | [diff] [blame] | 227 | req->retries = retries; |
James Bottomley | 3921603 | 2005-06-15 18:48:29 -0500 | [diff] [blame] | 228 | req->timeout = timeout; |
Jens Axboe | 4aff5e2 | 2006-08-10 08:44:47 +0200 | [diff] [blame] | 229 | req->cmd_type = REQ_TYPE_BLOCK_PC; |
| 230 | req->cmd_flags |= flags | REQ_QUIET | REQ_PREEMPT; |
James Bottomley | 3921603 | 2005-06-15 18:48:29 -0500 | [diff] [blame] | 231 | |
| 232 | /* |
| 233 | * head injection *required* here otherwise quiesce won't work |
| 234 | */ |
| 235 | blk_execute_rq(req->q, NULL, req, 1); |
| 236 | |
Alan Stern | bdb2b8c | 2008-06-24 14:03:14 -0400 | [diff] [blame] | 237 | /* |
| 238 | * Some devices (USB mass-storage in particular) may transfer |
| 239 | * garbage data together with a residue indicating that the data |
| 240 | * is invalid. Prevent the garbage from being misinterpreted |
| 241 | * and prevent security leaks by zeroing out the excess data. |
| 242 | */ |
Tejun Heo | c3a4d78 | 2009-05-07 22:24:37 +0900 | [diff] [blame] | 243 | if (unlikely(req->resid_len > 0 && req->resid_len <= bufflen)) |
| 244 | memset(buffer + (bufflen - req->resid_len), 0, req->resid_len); |
Alan Stern | bdb2b8c | 2008-06-24 14:03:14 -0400 | [diff] [blame] | 245 | |
FUJITA Tomonori | f4f4e47 | 2008-12-04 14:24:39 +0900 | [diff] [blame] | 246 | if (resid) |
Tejun Heo | c3a4d78 | 2009-05-07 22:24:37 +0900 | [diff] [blame] | 247 | *resid = req->resid_len; |
James Bottomley | 3921603 | 2005-06-15 18:48:29 -0500 | [diff] [blame] | 248 | ret = req->errors; |
| 249 | out: |
| 250 | blk_put_request(req); |
| 251 | |
| 252 | return ret; |
| 253 | } |
James Bottomley | 33aa687 | 2005-08-28 11:31:14 -0500 | [diff] [blame] | 254 | EXPORT_SYMBOL(scsi_execute); |
James Bottomley | 3921603 | 2005-06-15 18:48:29 -0500 | [diff] [blame] | 255 | |
James Bottomley | ea73a9f | 2005-08-28 11:33:52 -0500 | [diff] [blame] | 256 | |
| 257 | int scsi_execute_req(struct scsi_device *sdev, const unsigned char *cmd, |
| 258 | int data_direction, void *buffer, unsigned bufflen, |
FUJITA Tomonori | f4f4e47 | 2008-12-04 14:24:39 +0900 | [diff] [blame] | 259 | struct scsi_sense_hdr *sshdr, int timeout, int retries, |
| 260 | int *resid) |
James Bottomley | ea73a9f | 2005-08-28 11:33:52 -0500 | [diff] [blame] | 261 | { |
| 262 | char *sense = NULL; |
akpm@osdl.org | 1ccb48b | 2005-06-26 00:12:51 -0700 | [diff] [blame] | 263 | int result; |
| 264 | |
James Bottomley | ea73a9f | 2005-08-28 11:33:52 -0500 | [diff] [blame] | 265 | if (sshdr) { |
Jes Sorensen | 24669f75 | 2006-01-16 10:31:18 -0500 | [diff] [blame] | 266 | sense = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO); |
James Bottomley | ea73a9f | 2005-08-28 11:33:52 -0500 | [diff] [blame] | 267 | if (!sense) |
| 268 | return DRIVER_ERROR << 24; |
James Bottomley | ea73a9f | 2005-08-28 11:33:52 -0500 | [diff] [blame] | 269 | } |
akpm@osdl.org | 1ccb48b | 2005-06-26 00:12:51 -0700 | [diff] [blame] | 270 | result = scsi_execute(sdev, cmd, data_direction, buffer, bufflen, |
FUJITA Tomonori | f4f4e47 | 2008-12-04 14:24:39 +0900 | [diff] [blame] | 271 | sense, timeout, retries, 0, resid); |
James Bottomley | ea73a9f | 2005-08-28 11:33:52 -0500 | [diff] [blame] | 272 | if (sshdr) |
James Bottomley | e514385 | 2005-08-09 11:55:36 -0500 | [diff] [blame] | 273 | scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, sshdr); |
James Bottomley | ea73a9f | 2005-08-28 11:33:52 -0500 | [diff] [blame] | 274 | |
| 275 | kfree(sense); |
| 276 | return result; |
| 277 | } |
| 278 | EXPORT_SYMBOL(scsi_execute_req); |
| 279 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 280 | /* |
| 281 | * Function: scsi_init_cmd_errh() |
| 282 | * |
| 283 | * Purpose: Initialize cmd fields related to error handling. |
| 284 | * |
| 285 | * Arguments: cmd - command that is ready to be queued. |
| 286 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 287 | * Notes: This function has the job of initializing a number of |
| 288 | * fields related to error handling. Typically this will |
| 289 | * be called once for each command, as required. |
| 290 | */ |
Christoph Hellwig | 631c228 | 2006-07-08 20:42:15 +0200 | [diff] [blame] | 291 | static void scsi_init_cmd_errh(struct scsi_cmnd *cmd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 292 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 293 | cmd->serial_number = 0; |
Boaz Harrosh | 30b0c37 | 2007-12-13 13:47:40 +0200 | [diff] [blame] | 294 | scsi_set_resid(cmd, 0); |
FUJITA Tomonori | b80ca4f | 2008-01-13 15:46:13 +0900 | [diff] [blame] | 295 | memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 296 | if (cmd->cmd_len == 0) |
Boaz Harrosh | db4742d | 2008-04-30 11:27:26 +0300 | [diff] [blame] | 297 | cmd->cmd_len = scsi_command_size(cmd->cmnd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 298 | } |
| 299 | |
| 300 | void scsi_device_unbusy(struct scsi_device *sdev) |
| 301 | { |
| 302 | struct Scsi_Host *shost = sdev->host; |
Mike Christie | f0c0a37 | 2008-08-17 15:24:38 -0500 | [diff] [blame] | 303 | struct scsi_target *starget = scsi_target(sdev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 304 | unsigned long flags; |
| 305 | |
| 306 | spin_lock_irqsave(shost->host_lock, flags); |
| 307 | shost->host_busy--; |
Mike Christie | f0c0a37 | 2008-08-17 15:24:38 -0500 | [diff] [blame] | 308 | starget->target_busy--; |
James Bottomley | 939647e | 2005-09-18 15:05:20 -0500 | [diff] [blame] | 309 | if (unlikely(scsi_host_in_recovery(shost) && |
Tejun Heo | ee7863b | 2006-05-15 20:57:20 +0900 | [diff] [blame] | 310 | (shost->host_failed || shost->host_eh_scheduled))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 311 | scsi_eh_wakeup(shost); |
| 312 | spin_unlock(shost->host_lock); |
| 152587d | 2005-04-12 16:22:06 -0500 | [diff] [blame] | 313 | spin_lock(sdev->request_queue->queue_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 314 | sdev->device_busy--; |
| 152587d | 2005-04-12 16:22:06 -0500 | [diff] [blame] | 315 | spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 316 | } |
| 317 | |
| 318 | /* |
| 319 | * Called for single_lun devices on IO completion. Clear starget_sdev_user, |
| 320 | * and call blk_run_queue for all the scsi_devices on the target - |
| 321 | * including current_sdev first. |
| 322 | * |
| 323 | * Called with *no* scsi locks held. |
| 324 | */ |
| 325 | static void scsi_single_lun_run(struct scsi_device *current_sdev) |
| 326 | { |
| 327 | struct Scsi_Host *shost = current_sdev->host; |
| 328 | struct scsi_device *sdev, *tmp; |
| 329 | struct scsi_target *starget = scsi_target(current_sdev); |
| 330 | unsigned long flags; |
| 331 | |
| 332 | spin_lock_irqsave(shost->host_lock, flags); |
| 333 | starget->starget_sdev_user = NULL; |
| 334 | spin_unlock_irqrestore(shost->host_lock, flags); |
| 335 | |
| 336 | /* |
| 337 | * Call blk_run_queue for all LUNs on the target, starting with |
| 338 | * current_sdev. We race with others (to set starget_sdev_user), |
| 339 | * but in most cases, we will be first. Ideally, each LU on the |
| 340 | * target would get some limited time or requests on the target. |
| 341 | */ |
| 342 | blk_run_queue(current_sdev->request_queue); |
| 343 | |
| 344 | spin_lock_irqsave(shost->host_lock, flags); |
| 345 | if (starget->starget_sdev_user) |
| 346 | goto out; |
| 347 | list_for_each_entry_safe(sdev, tmp, &starget->devices, |
| 348 | same_target_siblings) { |
| 349 | if (sdev == current_sdev) |
| 350 | continue; |
| 351 | if (scsi_device_get(sdev)) |
| 352 | continue; |
| 353 | |
| 354 | spin_unlock_irqrestore(shost->host_lock, flags); |
| 355 | blk_run_queue(sdev->request_queue); |
| 356 | spin_lock_irqsave(shost->host_lock, flags); |
| 357 | |
| 358 | scsi_device_put(sdev); |
| 359 | } |
| 360 | out: |
| 361 | spin_unlock_irqrestore(shost->host_lock, flags); |
| 362 | } |
| 363 | |
Kiyoshi Ueda | 9d11251 | 2008-10-04 14:11:06 -0400 | [diff] [blame] | 364 | static inline int scsi_device_is_busy(struct scsi_device *sdev) |
| 365 | { |
| 366 | if (sdev->device_busy >= sdev->queue_depth || sdev->device_blocked) |
| 367 | return 1; |
| 368 | |
| 369 | return 0; |
| 370 | } |
| 371 | |
Mike Christie | f0c0a37 | 2008-08-17 15:24:38 -0500 | [diff] [blame] | 372 | static inline int scsi_target_is_busy(struct scsi_target *starget) |
| 373 | { |
| 374 | return ((starget->can_queue > 0 && |
| 375 | starget->target_busy >= starget->can_queue) || |
| 376 | starget->target_blocked); |
| 377 | } |
| 378 | |
Kiyoshi Ueda | 9d11251 | 2008-10-04 14:11:06 -0400 | [diff] [blame] | 379 | static inline int scsi_host_is_busy(struct Scsi_Host *shost) |
| 380 | { |
| 381 | if ((shost->can_queue > 0 && shost->host_busy >= shost->can_queue) || |
| 382 | shost->host_blocked || shost->host_self_blocked) |
| 383 | return 1; |
| 384 | |
| 385 | return 0; |
| 386 | } |
| 387 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 388 | /* |
| 389 | * Function: scsi_run_queue() |
| 390 | * |
| 391 | * Purpose: Select a proper request queue to serve next |
| 392 | * |
| 393 | * Arguments: q - last request's queue |
| 394 | * |
| 395 | * Returns: Nothing |
| 396 | * |
| 397 | * Notes: The previous command was completely finished, start |
| 398 | * a new one if possible. |
| 399 | */ |
| 400 | static void scsi_run_queue(struct request_queue *q) |
| 401 | { |
Mike Christie | 2a3a59e | 2008-11-11 13:42:35 -0600 | [diff] [blame] | 402 | struct scsi_device *sdev = q->queuedata; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 403 | struct Scsi_Host *shost = sdev->host; |
Mike Christie | 2a3a59e | 2008-11-11 13:42:35 -0600 | [diff] [blame] | 404 | LIST_HEAD(starved_list); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 405 | unsigned long flags; |
| 406 | |
Tony Battersby | 25d7c36 | 2007-11-12 10:00:44 -0500 | [diff] [blame] | 407 | if (scsi_target(sdev)->single_lun) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 408 | scsi_single_lun_run(sdev); |
| 409 | |
| 410 | spin_lock_irqsave(shost->host_lock, flags); |
Mike Christie | 2a3a59e | 2008-11-11 13:42:35 -0600 | [diff] [blame] | 411 | list_splice_init(&shost->starved_list, &starved_list); |
| 412 | |
| 413 | while (!list_empty(&starved_list)) { |
Nick Piggin | 75ad23b | 2008-04-29 14:48:33 +0200 | [diff] [blame] | 414 | int flagset; |
| 415 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 416 | /* |
| 417 | * As long as shost is accepting commands and we have |
| 418 | * starved queues, call blk_run_queue. scsi_request_fn |
| 419 | * drops the queue_lock and can add us back to the |
| 420 | * starved_list. |
| 421 | * |
| 422 | * host_lock protects the starved_list and starved_entry. |
| 423 | * scsi_request_fn must get the host_lock before checking |
| 424 | * or modifying starved_list or starved_entry. |
| 425 | */ |
Mike Christie | 2a3a59e | 2008-11-11 13:42:35 -0600 | [diff] [blame] | 426 | if (scsi_host_is_busy(shost)) |
Mike Christie | f0c0a37 | 2008-08-17 15:24:38 -0500 | [diff] [blame] | 427 | break; |
Mike Christie | f0c0a37 | 2008-08-17 15:24:38 -0500 | [diff] [blame] | 428 | |
Mike Christie | 2a3a59e | 2008-11-11 13:42:35 -0600 | [diff] [blame] | 429 | sdev = list_entry(starved_list.next, |
| 430 | struct scsi_device, starved_entry); |
| 431 | list_del_init(&sdev->starved_entry); |
Mike Christie | f0c0a37 | 2008-08-17 15:24:38 -0500 | [diff] [blame] | 432 | if (scsi_target_is_busy(scsi_target(sdev))) { |
| 433 | list_move_tail(&sdev->starved_entry, |
| 434 | &shost->starved_list); |
| 435 | continue; |
| 436 | } |
| 437 | |
Nick Piggin | 75ad23b | 2008-04-29 14:48:33 +0200 | [diff] [blame] | 438 | spin_unlock(shost->host_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 439 | |
Nick Piggin | 75ad23b | 2008-04-29 14:48:33 +0200 | [diff] [blame] | 440 | spin_lock(sdev->request_queue->queue_lock); |
| 441 | flagset = test_bit(QUEUE_FLAG_REENTER, &q->queue_flags) && |
| 442 | !test_bit(QUEUE_FLAG_REENTER, |
| 443 | &sdev->request_queue->queue_flags); |
| 444 | if (flagset) |
| 445 | queue_flag_set(QUEUE_FLAG_REENTER, sdev->request_queue); |
| 446 | __blk_run_queue(sdev->request_queue); |
| 447 | if (flagset) |
| 448 | queue_flag_clear(QUEUE_FLAG_REENTER, sdev->request_queue); |
| 449 | spin_unlock(sdev->request_queue->queue_lock); |
Andreas Herrmann | 04846f2 | 2006-08-09 17:31:16 +0200 | [diff] [blame] | 450 | |
Nick Piggin | 75ad23b | 2008-04-29 14:48:33 +0200 | [diff] [blame] | 451 | spin_lock(shost->host_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 452 | } |
Mike Christie | 2a3a59e | 2008-11-11 13:42:35 -0600 | [diff] [blame] | 453 | /* put any unprocessed entries back */ |
| 454 | list_splice(&starved_list, &shost->starved_list); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 455 | spin_unlock_irqrestore(shost->host_lock, flags); |
| 456 | |
| 457 | blk_run_queue(q); |
| 458 | } |
| 459 | |
| 460 | /* |
| 461 | * Function: scsi_requeue_command() |
| 462 | * |
| 463 | * Purpose: Handle post-processing of completed commands. |
| 464 | * |
| 465 | * Arguments: q - queue to operate on |
| 466 | * cmd - command that may need to be requeued. |
| 467 | * |
| 468 | * Returns: Nothing |
| 469 | * |
| 470 | * Notes: After command completion, there may be blocks left |
| 471 | * over which weren't finished by the previous command |
| 472 | * this can be for a number of reasons - the main one is |
| 473 | * I/O errors in the middle of the request, in which case |
| 474 | * we need to request the blocks that come after the bad |
| 475 | * sector. |
James Bottomley | e91442b | 2005-09-09 10:44:16 -0500 | [diff] [blame] | 476 | * Notes: Upon return, cmd is a stale pointer. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 477 | */ |
| 478 | static void scsi_requeue_command(struct request_queue *q, struct scsi_cmnd *cmd) |
| 479 | { |
James Bottomley | e91442b | 2005-09-09 10:44:16 -0500 | [diff] [blame] | 480 | struct request *req = cmd->request; |
Tejun Heo | 283369c | 2005-04-24 02:06:36 -0500 | [diff] [blame] | 481 | unsigned long flags; |
| 482 | |
Tejun Heo | 283369c | 2005-04-24 02:06:36 -0500 | [diff] [blame] | 483 | spin_lock_irqsave(q->queue_lock, flags); |
James Bottomley | 02bd349 | 2008-12-12 13:28:29 -0600 | [diff] [blame] | 484 | scsi_unprep_request(req); |
James Bottomley | e91442b | 2005-09-09 10:44:16 -0500 | [diff] [blame] | 485 | blk_requeue_request(q, req); |
Tejun Heo | 283369c | 2005-04-24 02:06:36 -0500 | [diff] [blame] | 486 | spin_unlock_irqrestore(q->queue_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 487 | |
| 488 | scsi_run_queue(q); |
| 489 | } |
| 490 | |
| 491 | void scsi_next_command(struct scsi_cmnd *cmd) |
| 492 | { |
Linus Torvalds | 49d7bc6 | 2005-12-12 11:25:04 -0800 | [diff] [blame] | 493 | struct scsi_device *sdev = cmd->device; |
| 494 | struct request_queue *q = sdev->request_queue; |
| 495 | |
| 496 | /* need to hold a reference on the device before we let go of the cmd */ |
| 497 | get_device(&sdev->sdev_gendev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 498 | |
| 499 | scsi_put_command(cmd); |
| 500 | scsi_run_queue(q); |
Linus Torvalds | 49d7bc6 | 2005-12-12 11:25:04 -0800 | [diff] [blame] | 501 | |
| 502 | /* ok to remove device now */ |
| 503 | put_device(&sdev->sdev_gendev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 504 | } |
| 505 | |
| 506 | void scsi_run_host_queues(struct Scsi_Host *shost) |
| 507 | { |
| 508 | struct scsi_device *sdev; |
| 509 | |
| 510 | shost_for_each_device(sdev, shost) |
| 511 | scsi_run_queue(sdev->request_queue); |
| 512 | } |
| 513 | |
James Bottomley | 79ed242 | 2009-01-06 13:15:20 -0600 | [diff] [blame] | 514 | static void __scsi_release_buffers(struct scsi_cmnd *, int); |
| 515 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 516 | /* |
| 517 | * Function: scsi_end_request() |
| 518 | * |
| 519 | * Purpose: Post-processing of completed commands (usually invoked at end |
| 520 | * of upper level post-processing and scsi_io_completion). |
| 521 | * |
| 522 | * Arguments: cmd - command that is complete. |
Kiyoshi Ueda | 610d8b0 | 2007-12-11 17:52:09 -0500 | [diff] [blame] | 523 | * error - 0 if I/O indicates success, < 0 for I/O error. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 524 | * bytes - number of bytes of completed I/O |
| 525 | * requeue - indicates whether we should requeue leftovers. |
| 526 | * |
| 527 | * Lock status: Assumed that lock is not held upon entry. |
| 528 | * |
James Bottomley | e91442b | 2005-09-09 10:44:16 -0500 | [diff] [blame] | 529 | * Returns: cmd if requeue required, NULL otherwise. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 530 | * |
| 531 | * Notes: This is called for block device requests in order to |
| 532 | * mark some number of sectors as complete. |
| 533 | * |
| 534 | * We are guaranteeing that the request queue will be goosed |
| 535 | * at some point during this call. |
James Bottomley | e91442b | 2005-09-09 10:44:16 -0500 | [diff] [blame] | 536 | * Notes: If cmd was requeued, upon return it will be a stale pointer. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 537 | */ |
Kiyoshi Ueda | 610d8b0 | 2007-12-11 17:52:09 -0500 | [diff] [blame] | 538 | static struct scsi_cmnd *scsi_end_request(struct scsi_cmnd *cmd, int error, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 539 | int bytes, int requeue) |
| 540 | { |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 541 | struct request_queue *q = cmd->device->request_queue; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 542 | struct request *req = cmd->request; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 543 | |
| 544 | /* |
| 545 | * If there are blocks left over at the end, set up the command |
| 546 | * to queue the remainder of them. |
| 547 | */ |
Kiyoshi Ueda | 610d8b0 | 2007-12-11 17:52:09 -0500 | [diff] [blame] | 548 | if (blk_end_request(req, error, bytes)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 549 | /* kill remainder if no retrys */ |
Mike Christie | 4a27446 | 2008-08-19 18:45:31 -0500 | [diff] [blame] | 550 | if (error && scsi_noretry_cmd(cmd)) |
Tejun Heo | e458824 | 2009-05-12 08:49:32 +0200 | [diff] [blame] | 551 | blk_end_request_all(req, error); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 552 | else { |
James Bottomley | e91442b | 2005-09-09 10:44:16 -0500 | [diff] [blame] | 553 | if (requeue) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 554 | /* |
| 555 | * Bleah. Leftovers again. Stick the |
| 556 | * leftovers in the front of the |
| 557 | * queue, and goose the queue again. |
| 558 | */ |
James Bottomley | 79ed242 | 2009-01-06 13:15:20 -0600 | [diff] [blame] | 559 | scsi_release_buffers(cmd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 560 | scsi_requeue_command(q, cmd); |
James Bottomley | e91442b | 2005-09-09 10:44:16 -0500 | [diff] [blame] | 561 | cmd = NULL; |
| 562 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 563 | return cmd; |
| 564 | } |
| 565 | } |
| 566 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 567 | /* |
| 568 | * This will goose the queue request function at the end, so we don't |
| 569 | * need to worry about launching another command. |
| 570 | */ |
James Bottomley | 79ed242 | 2009-01-06 13:15:20 -0600 | [diff] [blame] | 571 | __scsi_release_buffers(cmd, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 572 | scsi_next_command(cmd); |
| 573 | return NULL; |
| 574 | } |
| 575 | |
Jens Axboe | a8474ce | 2007-08-07 09:02:51 +0200 | [diff] [blame] | 576 | static inline unsigned int scsi_sgtable_index(unsigned short nents) |
| 577 | { |
| 578 | unsigned int index; |
| 579 | |
James Bottomley | d3f46f3 | 2008-01-15 11:11:46 -0600 | [diff] [blame] | 580 | BUG_ON(nents > SCSI_MAX_SG_SEGMENTS); |
| 581 | |
| 582 | if (nents <= 8) |
Jens Axboe | a8474ce | 2007-08-07 09:02:51 +0200 | [diff] [blame] | 583 | index = 0; |
James Bottomley | d3f46f3 | 2008-01-15 11:11:46 -0600 | [diff] [blame] | 584 | else |
| 585 | index = get_count_order(nents) - 3; |
Jens Axboe | a8474ce | 2007-08-07 09:02:51 +0200 | [diff] [blame] | 586 | |
| 587 | return index; |
| 588 | } |
| 589 | |
Jens Axboe | 5ed7959 | 2007-11-15 09:13:11 +0100 | [diff] [blame] | 590 | static void scsi_sg_free(struct scatterlist *sgl, unsigned int nents) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 591 | { |
| 592 | struct scsi_host_sg_pool *sgp; |
Jens Axboe | 5ed7959 | 2007-11-15 09:13:11 +0100 | [diff] [blame] | 593 | |
| 594 | sgp = scsi_sg_pools + scsi_sgtable_index(nents); |
| 595 | mempool_free(sgl, sgp->pool); |
| 596 | } |
| 597 | |
| 598 | static struct scatterlist *scsi_sg_alloc(unsigned int nents, gfp_t gfp_mask) |
| 599 | { |
| 600 | struct scsi_host_sg_pool *sgp; |
| 601 | |
| 602 | sgp = scsi_sg_pools + scsi_sgtable_index(nents); |
| 603 | return mempool_alloc(sgp->pool, gfp_mask); |
| 604 | } |
| 605 | |
Boaz Harrosh | 30b0c37 | 2007-12-13 13:47:40 +0200 | [diff] [blame] | 606 | static int scsi_alloc_sgtable(struct scsi_data_buffer *sdb, int nents, |
| 607 | gfp_t gfp_mask) |
Jens Axboe | 5ed7959 | 2007-11-15 09:13:11 +0100 | [diff] [blame] | 608 | { |
| 609 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 610 | |
Boaz Harrosh | 30b0c37 | 2007-12-13 13:47:40 +0200 | [diff] [blame] | 611 | BUG_ON(!nents); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 612 | |
Boaz Harrosh | 30b0c37 | 2007-12-13 13:47:40 +0200 | [diff] [blame] | 613 | ret = __sg_alloc_table(&sdb->table, nents, SCSI_MAX_SG_SEGMENTS, |
| 614 | gfp_mask, scsi_sg_alloc); |
Jens Axboe | 5ed7959 | 2007-11-15 09:13:11 +0100 | [diff] [blame] | 615 | if (unlikely(ret)) |
Boaz Harrosh | 30b0c37 | 2007-12-13 13:47:40 +0200 | [diff] [blame] | 616 | __sg_free_table(&sdb->table, SCSI_MAX_SG_SEGMENTS, |
James Bottomley | 7cedb1f | 2008-01-13 14:15:28 -0600 | [diff] [blame] | 617 | scsi_sg_free); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 618 | |
Jens Axboe | a8474ce | 2007-08-07 09:02:51 +0200 | [diff] [blame] | 619 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 620 | } |
| 621 | |
Boaz Harrosh | 30b0c37 | 2007-12-13 13:47:40 +0200 | [diff] [blame] | 622 | static void scsi_free_sgtable(struct scsi_data_buffer *sdb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 623 | { |
Boaz Harrosh | 30b0c37 | 2007-12-13 13:47:40 +0200 | [diff] [blame] | 624 | __sg_free_table(&sdb->table, SCSI_MAX_SG_SEGMENTS, scsi_sg_free); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 625 | } |
| 626 | |
James Bottomley | 79ed242 | 2009-01-06 13:15:20 -0600 | [diff] [blame] | 627 | static void __scsi_release_buffers(struct scsi_cmnd *cmd, int do_bidi_check) |
| 628 | { |
| 629 | |
| 630 | if (cmd->sdb.table.nents) |
| 631 | scsi_free_sgtable(&cmd->sdb); |
| 632 | |
| 633 | memset(&cmd->sdb, 0, sizeof(cmd->sdb)); |
| 634 | |
| 635 | if (do_bidi_check && scsi_bidi_cmnd(cmd)) { |
| 636 | struct scsi_data_buffer *bidi_sdb = |
| 637 | cmd->request->next_rq->special; |
| 638 | scsi_free_sgtable(bidi_sdb); |
| 639 | kmem_cache_free(scsi_sdb_cache, bidi_sdb); |
| 640 | cmd->request->next_rq->special = NULL; |
| 641 | } |
| 642 | |
| 643 | if (scsi_prot_sg_count(cmd)) |
| 644 | scsi_free_sgtable(cmd->prot_sdb); |
| 645 | } |
| 646 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 647 | /* |
| 648 | * Function: scsi_release_buffers() |
| 649 | * |
| 650 | * Purpose: Completion processing for block device I/O requests. |
| 651 | * |
| 652 | * Arguments: cmd - command that we are bailing. |
| 653 | * |
| 654 | * Lock status: Assumed that no lock is held upon entry. |
| 655 | * |
| 656 | * Returns: Nothing |
| 657 | * |
| 658 | * Notes: In the event that an upper level driver rejects a |
| 659 | * command, we must release resources allocated during |
| 660 | * the __init_io() function. Primarily this would involve |
| 661 | * the scatter-gather table, and potentially any bounce |
| 662 | * buffers. |
| 663 | */ |
Boaz Harrosh | bb52d82 | 2007-12-13 16:14:27 -0800 | [diff] [blame] | 664 | void scsi_release_buffers(struct scsi_cmnd *cmd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 665 | { |
James Bottomley | 79ed242 | 2009-01-06 13:15:20 -0600 | [diff] [blame] | 666 | __scsi_release_buffers(cmd, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 667 | } |
Boaz Harrosh | bb52d82 | 2007-12-13 16:14:27 -0800 | [diff] [blame] | 668 | EXPORT_SYMBOL(scsi_release_buffers); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 669 | |
| 670 | /* |
| 671 | * Function: scsi_io_completion() |
| 672 | * |
| 673 | * Purpose: Completion processing for block device I/O requests. |
| 674 | * |
| 675 | * Arguments: cmd - command that is finished. |
| 676 | * |
| 677 | * Lock status: Assumed that no lock is held upon entry. |
| 678 | * |
| 679 | * Returns: Nothing |
| 680 | * |
| 681 | * Notes: This function is matched in terms of capabilities to |
| 682 | * the function that created the scatter-gather list. |
| 683 | * In other words, if there are no bounce buffers |
| 684 | * (the normal case for most drivers), we don't need |
| 685 | * the logic to deal with cleaning up afterwards. |
| 686 | * |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 687 | * We must call scsi_end_request(). This will finish off |
| 688 | * the specified number of sectors. If we are done, the |
| 689 | * command block will be released and the queue function |
| 690 | * will be goosed. If we are not done then we have to |
| 691 | * figure out what to do next: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 692 | * |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 693 | * a) We can call scsi_requeue_command(). The request |
| 694 | * will be unprepared and put back on the queue. Then |
| 695 | * a new command will be created for it. This should |
| 696 | * be used if we made forward progress, or if we want |
| 697 | * to switch from READ(10) to READ(6) for example. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 698 | * |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 699 | * b) We can call scsi_queue_insert(). The request will |
| 700 | * be put back on the queue and retried using the same |
| 701 | * command as before, possibly after a delay. |
| 702 | * |
| 703 | * c) We can call blk_end_request() with -EIO to fail |
| 704 | * the remainder of the request. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 705 | */ |
Luben Tuikov | 03aba2f | 2006-06-23 09:39:09 -0700 | [diff] [blame] | 706 | void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 707 | { |
| 708 | int result = cmd->result; |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 709 | struct request_queue *q = cmd->device->request_queue; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 710 | struct request *req = cmd->request; |
James Bottomley | fa8e36c | 2008-04-02 18:11:52 -0500 | [diff] [blame] | 711 | int error = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 712 | struct scsi_sense_hdr sshdr; |
| 713 | int sense_valid = 0; |
| 714 | int sense_deferred = 0; |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 715 | enum {ACTION_FAIL, ACTION_REPREP, ACTION_RETRY, |
| 716 | ACTION_DELAYED_RETRY} action; |
| 717 | char *description = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 718 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 719 | if (result) { |
| 720 | sense_valid = scsi_command_normalize_sense(cmd, &sshdr); |
| 721 | if (sense_valid) |
| 722 | sense_deferred = scsi_sense_is_deferred(&sshdr); |
| 723 | } |
Christoph Hellwig | 631c228 | 2006-07-08 20:42:15 +0200 | [diff] [blame] | 724 | |
Christoph Hellwig | 33659eb | 2010-08-07 18:17:56 +0200 | [diff] [blame] | 725 | if (req->cmd_type == REQ_TYPE_BLOCK_PC) { /* SG_IO ioctl from block level */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 726 | req->errors = result; |
| 727 | if (result) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 728 | if (sense_valid && req->sense) { |
| 729 | /* |
| 730 | * SG_IO wants current and deferred errors |
| 731 | */ |
| 732 | int len = 8 + cmd->sense_buffer[7]; |
| 733 | |
| 734 | if (len > SCSI_SENSE_BUFFERSIZE) |
| 735 | len = SCSI_SENSE_BUFFERSIZE; |
| 736 | memcpy(req->sense, cmd->sense_buffer, len); |
| 737 | req->sense_len = len; |
| 738 | } |
James Bottomley | fa8e36c | 2008-04-02 18:11:52 -0500 | [diff] [blame] | 739 | if (!sense_deferred) |
| 740 | error = -EIO; |
Pete Wyckoff | b22f687 | 2007-03-13 16:53:28 -0400 | [diff] [blame] | 741 | } |
FUJITA Tomonori | e6bb7a96 | 2009-05-11 17:56:08 +0900 | [diff] [blame] | 742 | |
| 743 | req->resid_len = scsi_get_resid(cmd); |
| 744 | |
Boaz Harrosh | 6f9a35e | 2007-12-13 13:50:53 +0200 | [diff] [blame] | 745 | if (scsi_bidi_cmnd(cmd)) { |
FUJITA Tomonori | e6bb7a96 | 2009-05-11 17:56:08 +0900 | [diff] [blame] | 746 | /* |
| 747 | * Bidi commands Must be complete as a whole, |
| 748 | * both sides at once. |
| 749 | */ |
| 750 | req->next_rq->resid_len = scsi_in(cmd)->resid; |
| 751 | |
Boaz Harrosh | 63c43b0 | 2009-12-15 17:25:43 +0200 | [diff] [blame] | 752 | scsi_release_buffers(cmd); |
FUJITA Tomonori | e6bb7a96 | 2009-05-11 17:56:08 +0900 | [diff] [blame] | 753 | blk_end_request_all(req, 0); |
| 754 | |
FUJITA Tomonori | e6bb7a96 | 2009-05-11 17:56:08 +0900 | [diff] [blame] | 755 | scsi_next_command(cmd); |
Boaz Harrosh | 6f9a35e | 2007-12-13 13:50:53 +0200 | [diff] [blame] | 756 | return; |
| 757 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 758 | } |
| 759 | |
Christoph Hellwig | 33659eb | 2010-08-07 18:17:56 +0200 | [diff] [blame] | 760 | /* no bidi support for !REQ_TYPE_BLOCK_PC yet */ |
| 761 | BUG_ON(blk_bidi_rq(req)); |
Boaz Harrosh | 30b0c37 | 2007-12-13 13:47:40 +0200 | [diff] [blame] | 762 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 763 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 764 | * Next deal with any sectors which we were able to correctly |
| 765 | * handle. |
| 766 | */ |
Tejun Heo | 83096eb | 2009-05-07 22:24:39 +0900 | [diff] [blame] | 767 | SCSI_LOG_HLCOMPLETE(1, printk("%u sectors total, " |
James Bottomley | d6b0c53 | 2006-07-02 10:06:28 -0500 | [diff] [blame] | 768 | "%d bytes done.\n", |
Tejun Heo | 83096eb | 2009-05-07 22:24:39 +0900 | [diff] [blame] | 769 | blk_rq_sectors(req), good_bytes)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 770 | |
James Bottomley | a9bddd7 | 2009-03-30 16:55:51 +0000 | [diff] [blame] | 771 | /* |
| 772 | * Recovered errors need reporting, but they're always treated |
| 773 | * as success, so fiddle the result code here. For BLOCK_PC |
| 774 | * we already took a copy of the original into rq->errors which |
| 775 | * is what gets returned to the user |
| 776 | */ |
Douglas Gilbert | e7efe59 | 2010-01-03 13:51:15 -0500 | [diff] [blame] | 777 | if (sense_valid && (sshdr.sense_key == RECOVERED_ERROR)) { |
| 778 | /* if ATA PASS-THROUGH INFORMATION AVAILABLE skip |
| 779 | * print since caller wants ATA registers. Only occurs on |
| 780 | * SCSI ATA PASS_THROUGH commands when CK_COND=1 |
| 781 | */ |
| 782 | if ((sshdr.asc == 0x0) && (sshdr.ascq == 0x1d)) |
| 783 | ; |
| 784 | else if (!(req->cmd_flags & REQ_QUIET)) |
James Bottomley | a9bddd7 | 2009-03-30 16:55:51 +0000 | [diff] [blame] | 785 | scsi_print_sense("", cmd); |
| 786 | result = 0; |
| 787 | /* BLOCK_PC may have set error */ |
| 788 | error = 0; |
| 789 | } |
| 790 | |
| 791 | /* |
| 792 | * A number of bytes were successfully read. If there |
James Bottomley | d6b0c53 | 2006-07-02 10:06:28 -0500 | [diff] [blame] | 793 | * are leftovers and there is some kind of error |
| 794 | * (result != 0), retry the rest. |
| 795 | */ |
James Bottomley | fa8e36c | 2008-04-02 18:11:52 -0500 | [diff] [blame] | 796 | if (scsi_end_request(cmd, error, good_bytes, result == 0) == NULL) |
James Bottomley | d6b0c53 | 2006-07-02 10:06:28 -0500 | [diff] [blame] | 797 | return; |
Luben Tuikov | 03aba2f | 2006-06-23 09:39:09 -0700 | [diff] [blame] | 798 | |
Martin K. Petersen | 3e695f8 | 2009-01-04 03:04:31 -0500 | [diff] [blame] | 799 | error = -EIO; |
| 800 | |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 801 | if (host_byte(result) == DID_RESET) { |
| 802 | /* Third party bus reset or reset for error recovery |
| 803 | * reasons. Just retry the command and see what |
| 804 | * happens. |
| 805 | */ |
| 806 | action = ACTION_RETRY; |
| 807 | } else if (sense_valid && !sense_deferred) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 808 | switch (sshdr.sense_key) { |
| 809 | case UNIT_ATTENTION: |
| 810 | if (cmd->device->removable) { |
Luben Tuikov | 03aba2f | 2006-06-23 09:39:09 -0700 | [diff] [blame] | 811 | /* Detected disc change. Set a bit |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 812 | * and quietly refuse further access. |
| 813 | */ |
| 814 | cmd->device->changed = 1; |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 815 | description = "Media Changed"; |
| 816 | action = ACTION_FAIL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 817 | } else { |
Luben Tuikov | 03aba2f | 2006-06-23 09:39:09 -0700 | [diff] [blame] | 818 | /* Must have been a power glitch, or a |
| 819 | * bus reset. Could not have been a |
| 820 | * media change, so we just retry the |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 821 | * command and see what happens. |
Luben Tuikov | 03aba2f | 2006-06-23 09:39:09 -0700 | [diff] [blame] | 822 | */ |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 823 | action = ACTION_RETRY; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 824 | } |
| 825 | break; |
| 826 | case ILLEGAL_REQUEST: |
Luben Tuikov | 03aba2f | 2006-06-23 09:39:09 -0700 | [diff] [blame] | 827 | /* If we had an ILLEGAL REQUEST returned, then |
| 828 | * we may have performed an unsupported |
| 829 | * command. The only thing this should be |
| 830 | * would be a ten byte read where only a six |
| 831 | * byte read was supported. Also, on a system |
| 832 | * where READ CAPACITY failed, we may have |
| 833 | * read past the end of the disk. |
| 834 | */ |
Jens Axboe | 26a6801 | 2005-11-29 21:03:34 +0100 | [diff] [blame] | 835 | if ((cmd->device->use_10_for_rw && |
| 836 | sshdr.asc == 0x20 && sshdr.ascq == 0x00) && |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 837 | (cmd->cmnd[0] == READ_10 || |
| 838 | cmd->cmnd[0] == WRITE_10)) { |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 839 | /* This will issue a new 6-byte command. */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 840 | cmd->device->use_10_for_rw = 0; |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 841 | action = ACTION_REPREP; |
Martin K. Petersen | 3e695f8 | 2009-01-04 03:04:31 -0500 | [diff] [blame] | 842 | } else if (sshdr.asc == 0x10) /* DIX */ { |
| 843 | description = "Host Data Integrity Failure"; |
| 844 | action = ACTION_FAIL; |
| 845 | error = -EILSEQ; |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 846 | } else |
| 847 | action = ACTION_FAIL; |
| 848 | break; |
Martin K. Petersen | 511e44f | 2008-07-17 04:28:33 -0400 | [diff] [blame] | 849 | case ABORTED_COMMAND: |
James Bottomley | 126c0982 | 2009-02-19 21:48:54 +0000 | [diff] [blame] | 850 | action = ACTION_FAIL; |
Martin K. Petersen | 511e44f | 2008-07-17 04:28:33 -0400 | [diff] [blame] | 851 | if (sshdr.asc == 0x10) { /* DIF */ |
Martin K. Petersen | 3e695f8 | 2009-01-04 03:04:31 -0500 | [diff] [blame] | 852 | description = "Target Data Integrity Failure"; |
Martin K. Petersen | 3e695f8 | 2009-01-04 03:04:31 -0500 | [diff] [blame] | 853 | error = -EILSEQ; |
James Bottomley | 126c0982 | 2009-02-19 21:48:54 +0000 | [diff] [blame] | 854 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 855 | break; |
| 856 | case NOT_READY: |
Luben Tuikov | 03aba2f | 2006-06-23 09:39:09 -0700 | [diff] [blame] | 857 | /* If the device is in the process of becoming |
James Bottomley | f3e93f7 | 2006-04-25 16:48:30 -0500 | [diff] [blame] | 858 | * ready, or has a temporary blockage, retry. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 859 | */ |
James Bottomley | f3e93f7 | 2006-04-25 16:48:30 -0500 | [diff] [blame] | 860 | if (sshdr.asc == 0x04) { |
| 861 | switch (sshdr.ascq) { |
| 862 | case 0x01: /* becoming ready */ |
| 863 | case 0x04: /* format in progress */ |
| 864 | case 0x05: /* rebuild in progress */ |
| 865 | case 0x06: /* recalculation in progress */ |
| 866 | case 0x07: /* operation in progress */ |
| 867 | case 0x08: /* Long write in progress */ |
| 868 | case 0x09: /* self test in progress */ |
Martin K. Petersen | d8705f1 | 2009-11-26 12:00:41 -0500 | [diff] [blame] | 869 | case 0x14: /* space allocation in progress */ |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 870 | action = ACTION_DELAYED_RETRY; |
James Bottomley | f3e93f7 | 2006-04-25 16:48:30 -0500 | [diff] [blame] | 871 | break; |
Alan Stern | 3dbf6a5 | 2008-12-15 10:31:28 -0500 | [diff] [blame] | 872 | default: |
| 873 | description = "Device not ready"; |
| 874 | action = ACTION_FAIL; |
| 875 | break; |
James Bottomley | f3e93f7 | 2006-04-25 16:48:30 -0500 | [diff] [blame] | 876 | } |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 877 | } else { |
| 878 | description = "Device not ready"; |
| 879 | action = ACTION_FAIL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 880 | } |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 881 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 882 | case VOLUME_OVERFLOW: |
Luben Tuikov | 03aba2f | 2006-06-23 09:39:09 -0700 | [diff] [blame] | 883 | /* See SSC3rXX or current. */ |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 884 | action = ACTION_FAIL; |
| 885 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 886 | default: |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 887 | description = "Unhandled sense code"; |
| 888 | action = ACTION_FAIL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 889 | break; |
| 890 | } |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 891 | } else { |
| 892 | description = "Unhandled error code"; |
| 893 | action = ACTION_FAIL; |
Luben Tuikov | 03aba2f | 2006-06-23 09:39:09 -0700 | [diff] [blame] | 894 | } |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 895 | |
| 896 | switch (action) { |
| 897 | case ACTION_FAIL: |
| 898 | /* Give up and fail the remainder of the request */ |
James Bottomley | 79ed242 | 2009-01-06 13:15:20 -0600 | [diff] [blame] | 899 | scsi_release_buffers(cmd); |
Jens Axboe | 4aff5e2 | 2006-08-10 08:44:47 +0200 | [diff] [blame] | 900 | if (!(req->cmd_flags & REQ_QUIET)) { |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 901 | if (description) |
Alan Stern | 3dbf6a5 | 2008-12-15 10:31:28 -0500 | [diff] [blame] | 902 | scmd_printk(KERN_INFO, cmd, "%s\n", |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 903 | description); |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 904 | scsi_print_result(cmd); |
James Bottomley | 3173d8c | 2005-09-04 11:32:05 -0500 | [diff] [blame] | 905 | if (driver_byte(result) & DRIVER_SENSE) |
| 906 | scsi_print_sense("", cmd); |
Martin K. Petersen | 002b1eb | 2009-05-23 11:45:07 -0400 | [diff] [blame] | 907 | scsi_print_command(cmd); |
James Bottomley | 3173d8c | 2005-09-04 11:32:05 -0500 | [diff] [blame] | 908 | } |
Mike Christie | ad63082 | 2009-09-28 15:50:52 -0500 | [diff] [blame] | 909 | if (blk_end_request_err(req, error)) |
Tejun Heo | da6c5c7 | 2009-09-11 14:26:40 +0200 | [diff] [blame] | 910 | scsi_requeue_command(q, cmd); |
| 911 | else |
| 912 | scsi_next_command(cmd); |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 913 | break; |
| 914 | case ACTION_REPREP: |
| 915 | /* Unprep the request and put it back at the head of the queue. |
| 916 | * A new command will be prepared and issued. |
| 917 | */ |
James Bottomley | 79ed242 | 2009-01-06 13:15:20 -0600 | [diff] [blame] | 918 | scsi_release_buffers(cmd); |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 919 | scsi_requeue_command(q, cmd); |
| 920 | break; |
| 921 | case ACTION_RETRY: |
| 922 | /* Retry the same command immediately */ |
James Bottomley | 4f5299a | 2009-01-02 10:42:21 -0600 | [diff] [blame] | 923 | __scsi_queue_insert(cmd, SCSI_MLQUEUE_EH_RETRY, 0); |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 924 | break; |
| 925 | case ACTION_DELAYED_RETRY: |
| 926 | /* Retry the same command after a delay */ |
James Bottomley | 4f5299a | 2009-01-02 10:42:21 -0600 | [diff] [blame] | 927 | __scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY, 0); |
Alan Stern | b60af5b | 2008-11-03 15:56:47 -0500 | [diff] [blame] | 928 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 929 | } |
| 930 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 931 | |
Boaz Harrosh | 6f9a35e | 2007-12-13 13:50:53 +0200 | [diff] [blame] | 932 | static int scsi_init_sgtable(struct request *req, struct scsi_data_buffer *sdb, |
| 933 | gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 934 | { |
Boaz Harrosh | 6f9a35e | 2007-12-13 13:50:53 +0200 | [diff] [blame] | 935 | int count; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 936 | |
| 937 | /* |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 938 | * If sg table allocation fails, requeue request later. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 939 | */ |
Boaz Harrosh | 30b0c37 | 2007-12-13 13:47:40 +0200 | [diff] [blame] | 940 | if (unlikely(scsi_alloc_sgtable(sdb, req->nr_phys_segments, |
| 941 | gfp_mask))) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 942 | return BLKPREP_DEFER; |
Alan Stern | 7c72ce8 | 2005-10-14 11:23:27 -0400 | [diff] [blame] | 943 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 944 | |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 945 | req->buffer = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 946 | |
| 947 | /* |
| 948 | * Next, walk the list, and fill in the addresses and sizes of |
| 949 | * each segment. |
| 950 | */ |
Boaz Harrosh | 30b0c37 | 2007-12-13 13:47:40 +0200 | [diff] [blame] | 951 | count = blk_rq_map_sg(req->q, req, sdb->table.sgl); |
| 952 | BUG_ON(count > sdb->table.nents); |
| 953 | sdb->table.nents = count; |
Tejun Heo | 1011c1b | 2009-05-07 22:24:45 +0900 | [diff] [blame] | 954 | sdb->length = blk_rq_bytes(req); |
Rusty Russell | 4a03d90 | 2007-11-19 11:28:48 +1100 | [diff] [blame] | 955 | return BLKPREP_OK; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 956 | } |
Boaz Harrosh | 6f9a35e | 2007-12-13 13:50:53 +0200 | [diff] [blame] | 957 | |
| 958 | /* |
| 959 | * Function: scsi_init_io() |
| 960 | * |
| 961 | * Purpose: SCSI I/O initialize function. |
| 962 | * |
| 963 | * Arguments: cmd - Command descriptor we wish to initialize |
| 964 | * |
| 965 | * Returns: 0 on success |
| 966 | * BLKPREP_DEFER if the failure is retryable |
| 967 | * BLKPREP_KILL if the failure is fatal |
| 968 | */ |
| 969 | int scsi_init_io(struct scsi_cmnd *cmd, gfp_t gfp_mask) |
| 970 | { |
Martin K. Petersen | 13f05c8 | 2010-09-10 20:50:10 +0200 | [diff] [blame] | 971 | struct request *rq = cmd->request; |
| 972 | |
| 973 | int error = scsi_init_sgtable(rq, &cmd->sdb, gfp_mask); |
Boaz Harrosh | 6f9a35e | 2007-12-13 13:50:53 +0200 | [diff] [blame] | 974 | if (error) |
| 975 | goto err_exit; |
| 976 | |
Martin K. Petersen | 13f05c8 | 2010-09-10 20:50:10 +0200 | [diff] [blame] | 977 | if (blk_bidi_rq(rq)) { |
Boaz Harrosh | 6f9a35e | 2007-12-13 13:50:53 +0200 | [diff] [blame] | 978 | struct scsi_data_buffer *bidi_sdb = kmem_cache_zalloc( |
Martin K. Petersen | 6362abd | 2008-06-05 23:30:03 -0400 | [diff] [blame] | 979 | scsi_sdb_cache, GFP_ATOMIC); |
Boaz Harrosh | 6f9a35e | 2007-12-13 13:50:53 +0200 | [diff] [blame] | 980 | if (!bidi_sdb) { |
| 981 | error = BLKPREP_DEFER; |
| 982 | goto err_exit; |
| 983 | } |
| 984 | |
Martin K. Petersen | 13f05c8 | 2010-09-10 20:50:10 +0200 | [diff] [blame] | 985 | rq->next_rq->special = bidi_sdb; |
| 986 | error = scsi_init_sgtable(rq->next_rq, bidi_sdb, GFP_ATOMIC); |
Boaz Harrosh | 6f9a35e | 2007-12-13 13:50:53 +0200 | [diff] [blame] | 987 | if (error) |
| 988 | goto err_exit; |
| 989 | } |
| 990 | |
Martin K. Petersen | 13f05c8 | 2010-09-10 20:50:10 +0200 | [diff] [blame] | 991 | if (blk_integrity_rq(rq)) { |
Martin K. Petersen | 7027ad7 | 2008-07-17 17:08:48 -0400 | [diff] [blame] | 992 | struct scsi_data_buffer *prot_sdb = cmd->prot_sdb; |
| 993 | int ivecs, count; |
| 994 | |
| 995 | BUG_ON(prot_sdb == NULL); |
Martin K. Petersen | 13f05c8 | 2010-09-10 20:50:10 +0200 | [diff] [blame] | 996 | ivecs = blk_rq_count_integrity_sg(rq->q, rq->bio); |
Martin K. Petersen | 7027ad7 | 2008-07-17 17:08:48 -0400 | [diff] [blame] | 997 | |
| 998 | if (scsi_alloc_sgtable(prot_sdb, ivecs, gfp_mask)) { |
| 999 | error = BLKPREP_DEFER; |
| 1000 | goto err_exit; |
| 1001 | } |
| 1002 | |
Martin K. Petersen | 13f05c8 | 2010-09-10 20:50:10 +0200 | [diff] [blame] | 1003 | count = blk_rq_map_integrity_sg(rq->q, rq->bio, |
Martin K. Petersen | 7027ad7 | 2008-07-17 17:08:48 -0400 | [diff] [blame] | 1004 | prot_sdb->table.sgl); |
| 1005 | BUG_ON(unlikely(count > ivecs)); |
Martin K. Petersen | 13f05c8 | 2010-09-10 20:50:10 +0200 | [diff] [blame] | 1006 | BUG_ON(unlikely(count > queue_max_integrity_segments(rq->q))); |
Martin K. Petersen | 7027ad7 | 2008-07-17 17:08:48 -0400 | [diff] [blame] | 1007 | |
| 1008 | cmd->prot_sdb = prot_sdb; |
| 1009 | cmd->prot_sdb->table.nents = count; |
| 1010 | } |
| 1011 | |
Boaz Harrosh | 6f9a35e | 2007-12-13 13:50:53 +0200 | [diff] [blame] | 1012 | return BLKPREP_OK ; |
| 1013 | |
| 1014 | err_exit: |
| 1015 | scsi_release_buffers(cmd); |
FUJITA Tomonori | 610a634 | 2010-07-08 10:16:17 +0200 | [diff] [blame] | 1016 | cmd->request->special = NULL; |
James Bottomley | 3a5c19c | 2010-08-16 10:06:26 -0500 | [diff] [blame] | 1017 | scsi_put_command(cmd); |
Boaz Harrosh | 6f9a35e | 2007-12-13 13:50:53 +0200 | [diff] [blame] | 1018 | return error; |
| 1019 | } |
Boaz Harrosh | bb52d82 | 2007-12-13 16:14:27 -0800 | [diff] [blame] | 1020 | EXPORT_SYMBOL(scsi_init_io); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1021 | |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1022 | static struct scsi_cmnd *scsi_get_cmd_from_req(struct scsi_device *sdev, |
| 1023 | struct request *req) |
| 1024 | { |
| 1025 | struct scsi_cmnd *cmd; |
| 1026 | |
| 1027 | if (!req->special) { |
| 1028 | cmd = scsi_get_command(sdev, GFP_ATOMIC); |
| 1029 | if (unlikely(!cmd)) |
| 1030 | return NULL; |
| 1031 | req->special = cmd; |
| 1032 | } else { |
| 1033 | cmd = req->special; |
| 1034 | } |
| 1035 | |
| 1036 | /* pull a tag out of the request if we have one */ |
| 1037 | cmd->tag = req->tag; |
| 1038 | cmd->request = req; |
| 1039 | |
Boaz Harrosh | 64a87b2 | 2008-04-30 11:19:47 +0300 | [diff] [blame] | 1040 | cmd->cmnd = req->cmd; |
| 1041 | |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1042 | return cmd; |
| 1043 | } |
| 1044 | |
James Bottomley | 7f9a6bc | 2007-08-04 10:06:25 -0500 | [diff] [blame] | 1045 | int scsi_setup_blk_pc_cmnd(struct scsi_device *sdev, struct request *req) |
James Bottomley | 7b16318 | 2005-12-15 20:17:02 -0600 | [diff] [blame] | 1046 | { |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1047 | struct scsi_cmnd *cmd; |
James Bottomley | 7f9a6bc | 2007-08-04 10:06:25 -0500 | [diff] [blame] | 1048 | int ret = scsi_prep_state_check(sdev, req); |
| 1049 | |
| 1050 | if (ret != BLKPREP_OK) |
| 1051 | return ret; |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1052 | |
| 1053 | cmd = scsi_get_cmd_from_req(sdev, req); |
| 1054 | if (unlikely(!cmd)) |
| 1055 | return BLKPREP_DEFER; |
| 1056 | |
| 1057 | /* |
| 1058 | * BLOCK_PC requests may transfer data, in which case they must |
| 1059 | * a bio attached to them. Or they might contain a SCSI command |
| 1060 | * that does not transfer data, in which case they may optionally |
| 1061 | * submit a request without an attached bio. |
| 1062 | */ |
| 1063 | if (req->bio) { |
| 1064 | int ret; |
| 1065 | |
| 1066 | BUG_ON(!req->nr_phys_segments); |
| 1067 | |
Boaz Harrosh | bb52d82 | 2007-12-13 16:14:27 -0800 | [diff] [blame] | 1068 | ret = scsi_init_io(cmd, GFP_ATOMIC); |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1069 | if (unlikely(ret)) |
| 1070 | return ret; |
| 1071 | } else { |
Tejun Heo | b079041 | 2009-05-07 22:24:42 +0900 | [diff] [blame] | 1072 | BUG_ON(blk_rq_bytes(req)); |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1073 | |
Boaz Harrosh | 30b0c37 | 2007-12-13 13:47:40 +0200 | [diff] [blame] | 1074 | memset(&cmd->sdb, 0, sizeof(cmd->sdb)); |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1075 | req->buffer = NULL; |
| 1076 | } |
James Bottomley | 7b16318 | 2005-12-15 20:17:02 -0600 | [diff] [blame] | 1077 | |
James Bottomley | 7b16318 | 2005-12-15 20:17:02 -0600 | [diff] [blame] | 1078 | cmd->cmd_len = req->cmd_len; |
Tejun Heo | b079041 | 2009-05-07 22:24:42 +0900 | [diff] [blame] | 1079 | if (!blk_rq_bytes(req)) |
James Bottomley | 7b16318 | 2005-12-15 20:17:02 -0600 | [diff] [blame] | 1080 | cmd->sc_data_direction = DMA_NONE; |
| 1081 | else if (rq_data_dir(req) == WRITE) |
| 1082 | cmd->sc_data_direction = DMA_TO_DEVICE; |
| 1083 | else |
| 1084 | cmd->sc_data_direction = DMA_FROM_DEVICE; |
| 1085 | |
Tejun Heo | b079041 | 2009-05-07 22:24:42 +0900 | [diff] [blame] | 1086 | cmd->transfersize = blk_rq_bytes(req); |
James Bottomley | 7b16318 | 2005-12-15 20:17:02 -0600 | [diff] [blame] | 1087 | cmd->allowed = req->retries; |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1088 | return BLKPREP_OK; |
| 1089 | } |
James Bottomley | 7f9a6bc | 2007-08-04 10:06:25 -0500 | [diff] [blame] | 1090 | EXPORT_SYMBOL(scsi_setup_blk_pc_cmnd); |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1091 | |
| 1092 | /* |
| 1093 | * Setup a REQ_TYPE_FS command. These are simple read/write request |
| 1094 | * from filesystems that still need to be translated to SCSI CDBs from |
| 1095 | * the ULD. |
| 1096 | */ |
James Bottomley | 7f9a6bc | 2007-08-04 10:06:25 -0500 | [diff] [blame] | 1097 | int scsi_setup_fs_cmnd(struct scsi_device *sdev, struct request *req) |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1098 | { |
| 1099 | struct scsi_cmnd *cmd; |
James Bottomley | 7f9a6bc | 2007-08-04 10:06:25 -0500 | [diff] [blame] | 1100 | int ret = scsi_prep_state_check(sdev, req); |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1101 | |
James Bottomley | 7f9a6bc | 2007-08-04 10:06:25 -0500 | [diff] [blame] | 1102 | if (ret != BLKPREP_OK) |
| 1103 | return ret; |
Chandra Seetharaman | a6a8d9f | 2008-05-01 14:49:46 -0700 | [diff] [blame] | 1104 | |
| 1105 | if (unlikely(sdev->scsi_dh_data && sdev->scsi_dh_data->scsi_dh |
| 1106 | && sdev->scsi_dh_data->scsi_dh->prep_fn)) { |
| 1107 | ret = sdev->scsi_dh_data->scsi_dh->prep_fn(sdev, req); |
| 1108 | if (ret != BLKPREP_OK) |
| 1109 | return ret; |
| 1110 | } |
| 1111 | |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1112 | /* |
| 1113 | * Filesystem requests must transfer data. |
| 1114 | */ |
| 1115 | BUG_ON(!req->nr_phys_segments); |
| 1116 | |
| 1117 | cmd = scsi_get_cmd_from_req(sdev, req); |
| 1118 | if (unlikely(!cmd)) |
| 1119 | return BLKPREP_DEFER; |
| 1120 | |
Boaz Harrosh | 64a87b2 | 2008-04-30 11:19:47 +0300 | [diff] [blame] | 1121 | memset(cmd->cmnd, 0, BLK_MAX_CDB); |
Boaz Harrosh | bb52d82 | 2007-12-13 16:14:27 -0800 | [diff] [blame] | 1122 | return scsi_init_io(cmd, GFP_ATOMIC); |
James Bottomley | 7b16318 | 2005-12-15 20:17:02 -0600 | [diff] [blame] | 1123 | } |
James Bottomley | 7f9a6bc | 2007-08-04 10:06:25 -0500 | [diff] [blame] | 1124 | EXPORT_SYMBOL(scsi_setup_fs_cmnd); |
James Bottomley | 7b16318 | 2005-12-15 20:17:02 -0600 | [diff] [blame] | 1125 | |
James Bottomley | 7f9a6bc | 2007-08-04 10:06:25 -0500 | [diff] [blame] | 1126 | int scsi_prep_state_check(struct scsi_device *sdev, struct request *req) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1127 | { |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1128 | int ret = BLKPREP_OK; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1129 | |
| 1130 | /* |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1131 | * If the device is not in running state we will reject some |
| 1132 | * or all commands. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1133 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1134 | if (unlikely(sdev->sdev_state != SDEV_RUNNING)) { |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1135 | switch (sdev->sdev_state) { |
| 1136 | case SDEV_OFFLINE: |
| 1137 | /* |
| 1138 | * If the device is offline we refuse to process any |
| 1139 | * commands. The device must be brought online |
| 1140 | * before trying any recovery commands. |
| 1141 | */ |
| 1142 | sdev_printk(KERN_ERR, sdev, |
| 1143 | "rejecting I/O to offline device\n"); |
| 1144 | ret = BLKPREP_KILL; |
| 1145 | break; |
| 1146 | case SDEV_DEL: |
| 1147 | /* |
| 1148 | * If the device is fully deleted, we refuse to |
| 1149 | * process any commands as well. |
| 1150 | */ |
James Bottomley | 9ccfc75 | 2005-10-02 11:45:08 -0500 | [diff] [blame] | 1151 | sdev_printk(KERN_ERR, sdev, |
| 1152 | "rejecting I/O to dead device\n"); |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1153 | ret = BLKPREP_KILL; |
| 1154 | break; |
| 1155 | case SDEV_QUIESCE: |
| 1156 | case SDEV_BLOCK: |
James Bottomley | 6f4267e | 2008-08-22 16:53:31 -0500 | [diff] [blame] | 1157 | case SDEV_CREATED_BLOCK: |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1158 | /* |
| 1159 | * If the devices is blocked we defer normal commands. |
| 1160 | */ |
| 1161 | if (!(req->cmd_flags & REQ_PREEMPT)) |
| 1162 | ret = BLKPREP_DEFER; |
| 1163 | break; |
| 1164 | default: |
| 1165 | /* |
| 1166 | * For any other not fully online state we only allow |
| 1167 | * special commands. In particular any user initiated |
| 1168 | * command is not allowed. |
| 1169 | */ |
| 1170 | if (!(req->cmd_flags & REQ_PREEMPT)) |
| 1171 | ret = BLKPREP_KILL; |
| 1172 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1173 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1174 | } |
James Bottomley | 7f9a6bc | 2007-08-04 10:06:25 -0500 | [diff] [blame] | 1175 | return ret; |
| 1176 | } |
| 1177 | EXPORT_SYMBOL(scsi_prep_state_check); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1178 | |
James Bottomley | 7f9a6bc | 2007-08-04 10:06:25 -0500 | [diff] [blame] | 1179 | int scsi_prep_return(struct request_queue *q, struct request *req, int ret) |
| 1180 | { |
| 1181 | struct scsi_device *sdev = q->queuedata; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1182 | |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1183 | switch (ret) { |
| 1184 | case BLKPREP_KILL: |
| 1185 | req->errors = DID_NO_CONNECT << 16; |
James Bottomley | 7f9a6bc | 2007-08-04 10:06:25 -0500 | [diff] [blame] | 1186 | /* release the command and kill it */ |
| 1187 | if (req->special) { |
| 1188 | struct scsi_cmnd *cmd = req->special; |
| 1189 | scsi_release_buffers(cmd); |
| 1190 | scsi_put_command(cmd); |
| 1191 | req->special = NULL; |
| 1192 | } |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1193 | break; |
| 1194 | case BLKPREP_DEFER: |
| 1195 | /* |
Tejun Heo | 9934c8c | 2009-05-08 11:54:16 +0900 | [diff] [blame] | 1196 | * If we defer, the blk_peek_request() returns NULL, but the |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1197 | * queue must be restarted, so we plug here if no returning |
| 1198 | * command will automatically do that. |
| 1199 | */ |
| 1200 | if (sdev->device_busy == 0) |
| 1201 | blk_plug_device(q); |
| 1202 | break; |
| 1203 | default: |
| 1204 | req->cmd_flags |= REQ_DONTPREP; |
| 1205 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1206 | |
Christoph Hellwig | 3b00315 | 2006-11-04 20:10:55 +0100 | [diff] [blame] | 1207 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1208 | } |
James Bottomley | 7f9a6bc | 2007-08-04 10:06:25 -0500 | [diff] [blame] | 1209 | EXPORT_SYMBOL(scsi_prep_return); |
| 1210 | |
James Bottomley | 751bf4d | 2008-01-02 11:14:30 -0600 | [diff] [blame] | 1211 | int scsi_prep_fn(struct request_queue *q, struct request *req) |
James Bottomley | 7f9a6bc | 2007-08-04 10:06:25 -0500 | [diff] [blame] | 1212 | { |
| 1213 | struct scsi_device *sdev = q->queuedata; |
| 1214 | int ret = BLKPREP_KILL; |
| 1215 | |
| 1216 | if (req->cmd_type == REQ_TYPE_BLOCK_PC) |
| 1217 | ret = scsi_setup_blk_pc_cmnd(sdev, req); |
| 1218 | return scsi_prep_return(q, req, ret); |
| 1219 | } |
Hannes Reinecke | b391277 | 2009-06-18 09:57:18 +0200 | [diff] [blame] | 1220 | EXPORT_SYMBOL(scsi_prep_fn); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1221 | |
| 1222 | /* |
| 1223 | * scsi_dev_queue_ready: if we can send requests to sdev, return 1 else |
| 1224 | * return 0. |
| 1225 | * |
| 1226 | * Called with the queue_lock held. |
| 1227 | */ |
| 1228 | static inline int scsi_dev_queue_ready(struct request_queue *q, |
| 1229 | struct scsi_device *sdev) |
| 1230 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1231 | if (sdev->device_busy == 0 && sdev->device_blocked) { |
| 1232 | /* |
| 1233 | * unblock after device_blocked iterates to zero |
| 1234 | */ |
| 1235 | if (--sdev->device_blocked == 0) { |
| 1236 | SCSI_LOG_MLQUEUE(3, |
James Bottomley | 9ccfc75 | 2005-10-02 11:45:08 -0500 | [diff] [blame] | 1237 | sdev_printk(KERN_INFO, sdev, |
| 1238 | "unblocking device at zero depth\n")); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1239 | } else { |
| 1240 | blk_plug_device(q); |
| 1241 | return 0; |
| 1242 | } |
| 1243 | } |
Kiyoshi Ueda | 9d11251 | 2008-10-04 14:11:06 -0400 | [diff] [blame] | 1244 | if (scsi_device_is_busy(sdev)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1245 | return 0; |
| 1246 | |
| 1247 | return 1; |
| 1248 | } |
| 1249 | |
Mike Christie | f0c0a37 | 2008-08-17 15:24:38 -0500 | [diff] [blame] | 1250 | |
| 1251 | /* |
| 1252 | * scsi_target_queue_ready: checks if there we can send commands to target |
| 1253 | * @sdev: scsi device on starget to check. |
| 1254 | * |
| 1255 | * Called with the host lock held. |
| 1256 | */ |
| 1257 | static inline int scsi_target_queue_ready(struct Scsi_Host *shost, |
| 1258 | struct scsi_device *sdev) |
| 1259 | { |
| 1260 | struct scsi_target *starget = scsi_target(sdev); |
| 1261 | |
| 1262 | if (starget->single_lun) { |
| 1263 | if (starget->starget_sdev_user && |
| 1264 | starget->starget_sdev_user != sdev) |
| 1265 | return 0; |
| 1266 | starget->starget_sdev_user = sdev; |
| 1267 | } |
| 1268 | |
| 1269 | if (starget->target_busy == 0 && starget->target_blocked) { |
| 1270 | /* |
| 1271 | * unblock after target_blocked iterates to zero |
| 1272 | */ |
| 1273 | if (--starget->target_blocked == 0) { |
| 1274 | SCSI_LOG_MLQUEUE(3, starget_printk(KERN_INFO, starget, |
| 1275 | "unblocking target at zero depth\n")); |
Mike Christie | b4efdd5 | 2009-04-09 15:57:10 -0500 | [diff] [blame] | 1276 | } else |
Mike Christie | f0c0a37 | 2008-08-17 15:24:38 -0500 | [diff] [blame] | 1277 | return 0; |
Mike Christie | f0c0a37 | 2008-08-17 15:24:38 -0500 | [diff] [blame] | 1278 | } |
| 1279 | |
| 1280 | if (scsi_target_is_busy(starget)) { |
| 1281 | if (list_empty(&sdev->starved_entry)) { |
| 1282 | list_add_tail(&sdev->starved_entry, |
| 1283 | &shost->starved_list); |
| 1284 | return 0; |
| 1285 | } |
| 1286 | } |
| 1287 | |
| 1288 | /* We're OK to process the command, so we can't be starved */ |
| 1289 | if (!list_empty(&sdev->starved_entry)) |
| 1290 | list_del_init(&sdev->starved_entry); |
| 1291 | return 1; |
| 1292 | } |
| 1293 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1294 | /* |
| 1295 | * scsi_host_queue_ready: if we can send requests to shost, return 1 else |
| 1296 | * return 0. We must end up running the queue again whenever 0 is |
| 1297 | * returned, else IO can hang. |
| 1298 | * |
| 1299 | * Called with host_lock held. |
| 1300 | */ |
| 1301 | static inline int scsi_host_queue_ready(struct request_queue *q, |
| 1302 | struct Scsi_Host *shost, |
| 1303 | struct scsi_device *sdev) |
| 1304 | { |
James Bottomley | 939647e | 2005-09-18 15:05:20 -0500 | [diff] [blame] | 1305 | if (scsi_host_in_recovery(shost)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1306 | return 0; |
| 1307 | if (shost->host_busy == 0 && shost->host_blocked) { |
| 1308 | /* |
| 1309 | * unblock after host_blocked iterates to zero |
| 1310 | */ |
| 1311 | if (--shost->host_blocked == 0) { |
| 1312 | SCSI_LOG_MLQUEUE(3, |
| 1313 | printk("scsi%d unblocking host at zero depth\n", |
| 1314 | shost->host_no)); |
| 1315 | } else { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1316 | return 0; |
| 1317 | } |
| 1318 | } |
Kiyoshi Ueda | 9d11251 | 2008-10-04 14:11:06 -0400 | [diff] [blame] | 1319 | if (scsi_host_is_busy(shost)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1320 | if (list_empty(&sdev->starved_entry)) |
| 1321 | list_add_tail(&sdev->starved_entry, &shost->starved_list); |
| 1322 | return 0; |
| 1323 | } |
| 1324 | |
| 1325 | /* We're OK to process the command, so we can't be starved */ |
| 1326 | if (!list_empty(&sdev->starved_entry)) |
| 1327 | list_del_init(&sdev->starved_entry); |
| 1328 | |
| 1329 | return 1; |
| 1330 | } |
| 1331 | |
| 1332 | /* |
Kiyoshi Ueda | 6c5121b | 2008-10-04 14:11:35 -0400 | [diff] [blame] | 1333 | * Busy state exporting function for request stacking drivers. |
| 1334 | * |
| 1335 | * For efficiency, no lock is taken to check the busy state of |
| 1336 | * shost/starget/sdev, since the returned value is not guaranteed and |
| 1337 | * may be changed after request stacking drivers call the function, |
| 1338 | * regardless of taking lock or not. |
| 1339 | * |
| 1340 | * When scsi can't dispatch I/Os anymore and needs to kill I/Os |
| 1341 | * (e.g. !sdev), scsi needs to return 'not busy'. |
| 1342 | * Otherwise, request stacking drivers may hold requests forever. |
| 1343 | */ |
| 1344 | static int scsi_lld_busy(struct request_queue *q) |
| 1345 | { |
| 1346 | struct scsi_device *sdev = q->queuedata; |
| 1347 | struct Scsi_Host *shost; |
| 1348 | struct scsi_target *starget; |
| 1349 | |
| 1350 | if (!sdev) |
| 1351 | return 0; |
| 1352 | |
| 1353 | shost = sdev->host; |
| 1354 | starget = scsi_target(sdev); |
| 1355 | |
| 1356 | if (scsi_host_in_recovery(shost) || scsi_host_is_busy(shost) || |
| 1357 | scsi_target_is_busy(starget) || scsi_device_is_busy(sdev)) |
| 1358 | return 1; |
| 1359 | |
| 1360 | return 0; |
| 1361 | } |
| 1362 | |
| 1363 | /* |
James Bottomley | e91442b | 2005-09-09 10:44:16 -0500 | [diff] [blame] | 1364 | * Kill a request for a dead device |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1365 | */ |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 1366 | static void scsi_kill_request(struct request *req, struct request_queue *q) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1367 | { |
James Bottomley | e91442b | 2005-09-09 10:44:16 -0500 | [diff] [blame] | 1368 | struct scsi_cmnd *cmd = req->special; |
Jiri Slaby | 03b1470 | 2009-09-23 16:15:35 +0200 | [diff] [blame] | 1369 | struct scsi_device *sdev; |
| 1370 | struct scsi_target *starget; |
| 1371 | struct Scsi_Host *shost; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1372 | |
Tejun Heo | 9934c8c | 2009-05-08 11:54:16 +0900 | [diff] [blame] | 1373 | blk_start_request(req); |
James Bottomley | 788ce43 | 2005-09-09 13:40:23 -0500 | [diff] [blame] | 1374 | |
Jiri Slaby | 03b1470 | 2009-09-23 16:15:35 +0200 | [diff] [blame] | 1375 | sdev = cmd->device; |
| 1376 | starget = scsi_target(sdev); |
| 1377 | shost = sdev->host; |
James Bottomley | e91442b | 2005-09-09 10:44:16 -0500 | [diff] [blame] | 1378 | scsi_init_cmd_errh(cmd); |
| 1379 | cmd->result = DID_NO_CONNECT << 16; |
| 1380 | atomic_inc(&cmd->device->iorequest_cnt); |
Tejun Heo | e36e0c8 | 2006-04-11 17:27:53 +0900 | [diff] [blame] | 1381 | |
| 1382 | /* |
| 1383 | * SCSI request completion path will do scsi_device_unbusy(), |
| 1384 | * bump busy counts. To bump the counters, we need to dance |
| 1385 | * with the locks as normal issue path does. |
| 1386 | */ |
| 1387 | sdev->device_busy++; |
| 1388 | spin_unlock(sdev->request_queue->queue_lock); |
| 1389 | spin_lock(shost->host_lock); |
| 1390 | shost->host_busy++; |
Mike Christie | f0c0a37 | 2008-08-17 15:24:38 -0500 | [diff] [blame] | 1391 | starget->target_busy++; |
Tejun Heo | e36e0c8 | 2006-04-11 17:27:53 +0900 | [diff] [blame] | 1392 | spin_unlock(shost->host_lock); |
| 1393 | spin_lock(sdev->request_queue->queue_lock); |
| 1394 | |
Jens Axboe | 242f9dc | 2008-09-14 05:55:09 -0700 | [diff] [blame] | 1395 | blk_complete_request(req); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1396 | } |
| 1397 | |
Jens Axboe | 1aea643 | 2006-01-09 16:03:03 +0100 | [diff] [blame] | 1398 | static void scsi_softirq_done(struct request *rq) |
| 1399 | { |
Jens Axboe | 242f9dc | 2008-09-14 05:55:09 -0700 | [diff] [blame] | 1400 | struct scsi_cmnd *cmd = rq->special; |
| 1401 | unsigned long wait_for = (cmd->allowed + 1) * rq->timeout; |
Jens Axboe | 1aea643 | 2006-01-09 16:03:03 +0100 | [diff] [blame] | 1402 | int disposition; |
| 1403 | |
| 1404 | INIT_LIST_HEAD(&cmd->eh_entry); |
| 1405 | |
Jens Axboe | 242f9dc | 2008-09-14 05:55:09 -0700 | [diff] [blame] | 1406 | atomic_inc(&cmd->device->iodone_cnt); |
| 1407 | if (cmd->result) |
| 1408 | atomic_inc(&cmd->device->ioerr_cnt); |
| 1409 | |
Jens Axboe | 1aea643 | 2006-01-09 16:03:03 +0100 | [diff] [blame] | 1410 | disposition = scsi_decide_disposition(cmd); |
| 1411 | if (disposition != SUCCESS && |
| 1412 | time_before(cmd->jiffies_at_alloc + wait_for, jiffies)) { |
| 1413 | sdev_printk(KERN_ERR, cmd->device, |
| 1414 | "timing out command, waited %lus\n", |
| 1415 | wait_for/HZ); |
| 1416 | disposition = SUCCESS; |
| 1417 | } |
| 1418 | |
| 1419 | scsi_log_completion(cmd, disposition); |
| 1420 | |
| 1421 | switch (disposition) { |
| 1422 | case SUCCESS: |
| 1423 | scsi_finish_command(cmd); |
| 1424 | break; |
| 1425 | case NEEDS_RETRY: |
Christoph Hellwig | 596f482 | 2007-01-02 12:56:00 +0100 | [diff] [blame] | 1426 | scsi_queue_insert(cmd, SCSI_MLQUEUE_EH_RETRY); |
Jens Axboe | 1aea643 | 2006-01-09 16:03:03 +0100 | [diff] [blame] | 1427 | break; |
| 1428 | case ADD_TO_MLQUEUE: |
| 1429 | scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY); |
| 1430 | break; |
| 1431 | default: |
| 1432 | if (!scsi_eh_scmd_add(cmd, 0)) |
| 1433 | scsi_finish_command(cmd); |
| 1434 | } |
| 1435 | } |
| 1436 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1437 | /* |
| 1438 | * Function: scsi_request_fn() |
| 1439 | * |
| 1440 | * Purpose: Main strategy routine for SCSI. |
| 1441 | * |
| 1442 | * Arguments: q - Pointer to actual queue. |
| 1443 | * |
| 1444 | * Returns: Nothing |
| 1445 | * |
| 1446 | * Lock status: IO request lock assumed to be held when called. |
| 1447 | */ |
| 1448 | static void scsi_request_fn(struct request_queue *q) |
| 1449 | { |
| 1450 | struct scsi_device *sdev = q->queuedata; |
| 1451 | struct Scsi_Host *shost; |
| 1452 | struct scsi_cmnd *cmd; |
| 1453 | struct request *req; |
| 1454 | |
| 1455 | if (!sdev) { |
| 1456 | printk("scsi: killing requests for dead queue\n"); |
Tejun Heo | 9934c8c | 2009-05-08 11:54:16 +0900 | [diff] [blame] | 1457 | while ((req = blk_peek_request(q)) != NULL) |
James Bottomley | e91442b | 2005-09-09 10:44:16 -0500 | [diff] [blame] | 1458 | scsi_kill_request(req, q); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1459 | return; |
| 1460 | } |
| 1461 | |
| 1462 | if(!get_device(&sdev->sdev_gendev)) |
| 1463 | /* We must be tearing the block queue down already */ |
| 1464 | return; |
| 1465 | |
| 1466 | /* |
| 1467 | * To start with, we keep looping until the queue is empty, or until |
| 1468 | * the host is no longer able to accept any more requests. |
| 1469 | */ |
| 1470 | shost = sdev->host; |
| 1471 | while (!blk_queue_plugged(q)) { |
| 1472 | int rtn; |
| 1473 | /* |
| 1474 | * get next queueable request. We do this early to make sure |
| 1475 | * that the request is fully prepared even if we cannot |
| 1476 | * accept it. |
| 1477 | */ |
Tejun Heo | 9934c8c | 2009-05-08 11:54:16 +0900 | [diff] [blame] | 1478 | req = blk_peek_request(q); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1479 | if (!req || !scsi_dev_queue_ready(q, sdev)) |
| 1480 | break; |
| 1481 | |
| 1482 | if (unlikely(!scsi_device_online(sdev))) { |
James Bottomley | 9ccfc75 | 2005-10-02 11:45:08 -0500 | [diff] [blame] | 1483 | sdev_printk(KERN_ERR, sdev, |
| 1484 | "rejecting I/O to offline device\n"); |
James Bottomley | e91442b | 2005-09-09 10:44:16 -0500 | [diff] [blame] | 1485 | scsi_kill_request(req, q); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1486 | continue; |
| 1487 | } |
| 1488 | |
| 1489 | |
| 1490 | /* |
| 1491 | * Remove the request from the request list. |
| 1492 | */ |
| 1493 | if (!(blk_queue_tagged(q) && !blk_queue_start_tag(q, req))) |
Tejun Heo | 9934c8c | 2009-05-08 11:54:16 +0900 | [diff] [blame] | 1494 | blk_start_request(req); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1495 | sdev->device_busy++; |
| 1496 | |
| 1497 | spin_unlock(q->queue_lock); |
James Bottomley | e91442b | 2005-09-09 10:44:16 -0500 | [diff] [blame] | 1498 | cmd = req->special; |
| 1499 | if (unlikely(cmd == NULL)) { |
| 1500 | printk(KERN_CRIT "impossible request in %s.\n" |
| 1501 | "please mail a stack trace to " |
Jens Axboe | 4aff5e2 | 2006-08-10 08:44:47 +0200 | [diff] [blame] | 1502 | "linux-scsi@vger.kernel.org\n", |
Harvey Harrison | cadbd4a | 2008-07-03 23:47:27 -0700 | [diff] [blame] | 1503 | __func__); |
Jens Axboe | 4aff5e2 | 2006-08-10 08:44:47 +0200 | [diff] [blame] | 1504 | blk_dump_rq_flags(req, "foo"); |
James Bottomley | e91442b | 2005-09-09 10:44:16 -0500 | [diff] [blame] | 1505 | BUG(); |
| 1506 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1507 | spin_lock(shost->host_lock); |
| 1508 | |
Mike Christie | ecefe8a | 2008-07-11 19:50:35 -0500 | [diff] [blame] | 1509 | /* |
| 1510 | * We hit this when the driver is using a host wide |
| 1511 | * tag map. For device level tag maps the queue_depth check |
| 1512 | * in the device ready fn would prevent us from trying |
| 1513 | * to allocate a tag. Since the map is a shared host resource |
| 1514 | * we add the dev to the starved list so it eventually gets |
| 1515 | * a run when a tag is freed. |
| 1516 | */ |
Mike Christie | 6bd522f | 2008-07-22 15:34:38 -0500 | [diff] [blame] | 1517 | if (blk_queue_tagged(q) && !blk_rq_tagged(req)) { |
Mike Christie | ecefe8a | 2008-07-11 19:50:35 -0500 | [diff] [blame] | 1518 | if (list_empty(&sdev->starved_entry)) |
| 1519 | list_add_tail(&sdev->starved_entry, |
| 1520 | &shost->starved_list); |
| 1521 | goto not_ready; |
| 1522 | } |
| 1523 | |
Mike Christie | f0c0a37 | 2008-08-17 15:24:38 -0500 | [diff] [blame] | 1524 | if (!scsi_target_queue_ready(shost, sdev)) |
| 1525 | goto not_ready; |
| 1526 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1527 | if (!scsi_host_queue_ready(q, shost, sdev)) |
| 1528 | goto not_ready; |
Mike Christie | f0c0a37 | 2008-08-17 15:24:38 -0500 | [diff] [blame] | 1529 | |
| 1530 | scsi_target(sdev)->target_busy++; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1531 | shost->host_busy++; |
| 1532 | |
| 1533 | /* |
| 1534 | * XXX(hch): This is rather suboptimal, scsi_dispatch_cmd will |
| 1535 | * take the lock again. |
| 1536 | */ |
| 1537 | spin_unlock_irq(shost->host_lock); |
| 1538 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1539 | /* |
| 1540 | * Finally, initialize any error handling parameters, and set up |
| 1541 | * the timers for timeouts. |
| 1542 | */ |
| 1543 | scsi_init_cmd_errh(cmd); |
| 1544 | |
| 1545 | /* |
| 1546 | * Dispatch the command to the low-level driver. |
| 1547 | */ |
| 1548 | rtn = scsi_dispatch_cmd(cmd); |
| 1549 | spin_lock_irq(q->queue_lock); |
| 1550 | if(rtn) { |
| 1551 | /* we're refusing the command; because of |
| 1552 | * the way locks get dropped, we need to |
| 1553 | * check here if plugging is required */ |
| 1554 | if(sdev->device_busy == 0) |
| 1555 | blk_plug_device(q); |
| 1556 | |
| 1557 | break; |
| 1558 | } |
| 1559 | } |
| 1560 | |
| 1561 | goto out; |
| 1562 | |
| 1563 | not_ready: |
| 1564 | spin_unlock_irq(shost->host_lock); |
| 1565 | |
| 1566 | /* |
| 1567 | * lock q, handle tag, requeue req, and decrement device_busy. We |
| 1568 | * must return with queue_lock held. |
| 1569 | * |
| 1570 | * Decrementing device_busy without checking it is OK, as all such |
| 1571 | * cases (host limits or settings) should run the queue at some |
| 1572 | * later time. |
| 1573 | */ |
| 1574 | spin_lock_irq(q->queue_lock); |
| 1575 | blk_requeue_request(q, req); |
| 1576 | sdev->device_busy--; |
| 1577 | if(sdev->device_busy == 0) |
| 1578 | blk_plug_device(q); |
| 1579 | out: |
| 1580 | /* must be careful here...if we trigger the ->remove() function |
| 1581 | * we cannot be holding the q lock */ |
| 1582 | spin_unlock_irq(q->queue_lock); |
| 1583 | put_device(&sdev->sdev_gendev); |
| 1584 | spin_lock_irq(q->queue_lock); |
| 1585 | } |
| 1586 | |
| 1587 | u64 scsi_calculate_bounce_limit(struct Scsi_Host *shost) |
| 1588 | { |
| 1589 | struct device *host_dev; |
| 1590 | u64 bounce_limit = 0xffffffff; |
| 1591 | |
| 1592 | if (shost->unchecked_isa_dma) |
| 1593 | return BLK_BOUNCE_ISA; |
| 1594 | /* |
| 1595 | * Platforms with virtual-DMA translation |
| 1596 | * hardware have no practical limit. |
| 1597 | */ |
| 1598 | if (!PCI_DMA_BUS_IS_PHYS) |
| 1599 | return BLK_BOUNCE_ANY; |
| 1600 | |
| 1601 | host_dev = scsi_get_device(shost); |
| 1602 | if (host_dev && host_dev->dma_mask) |
| 1603 | bounce_limit = *host_dev->dma_mask; |
| 1604 | |
| 1605 | return bounce_limit; |
| 1606 | } |
| 1607 | EXPORT_SYMBOL(scsi_calculate_bounce_limit); |
| 1608 | |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 1609 | struct request_queue *__scsi_alloc_queue(struct Scsi_Host *shost, |
| 1610 | request_fn_proc *request_fn) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1611 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1612 | struct request_queue *q; |
FUJITA Tomonori | 860ac56 | 2008-02-04 22:28:05 -0800 | [diff] [blame] | 1613 | struct device *dev = shost->shost_gendev.parent; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1614 | |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 1615 | q = blk_init_queue(request_fn, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1616 | if (!q) |
| 1617 | return NULL; |
| 1618 | |
Jens Axboe | a8474ce | 2007-08-07 09:02:51 +0200 | [diff] [blame] | 1619 | /* |
| 1620 | * this limit is imposed by hardware restrictions |
| 1621 | */ |
Martin K. Petersen | 8a78362 | 2010-02-26 00:20:39 -0500 | [diff] [blame] | 1622 | blk_queue_max_segments(q, min_t(unsigned short, shost->sg_tablesize, |
| 1623 | SCSI_MAX_SG_CHAIN_SEGMENTS)); |
Jens Axboe | a8474ce | 2007-08-07 09:02:51 +0200 | [diff] [blame] | 1624 | |
Martin K. Petersen | 13f05c8 | 2010-09-10 20:50:10 +0200 | [diff] [blame] | 1625 | if (scsi_host_prot_dma(shost)) { |
| 1626 | shost->sg_prot_tablesize = |
| 1627 | min_not_zero(shost->sg_prot_tablesize, |
| 1628 | (unsigned short)SCSI_MAX_PROT_SG_SEGMENTS); |
| 1629 | BUG_ON(shost->sg_prot_tablesize < shost->sg_tablesize); |
| 1630 | blk_queue_max_integrity_segments(q, shost->sg_prot_tablesize); |
| 1631 | } |
| 1632 | |
Martin K. Petersen | 086fa5f | 2010-02-26 00:20:38 -0500 | [diff] [blame] | 1633 | blk_queue_max_hw_sectors(q, shost->max_sectors); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1634 | blk_queue_bounce_limit(q, scsi_calculate_bounce_limit(shost)); |
| 1635 | blk_queue_segment_boundary(q, shost->dma_boundary); |
FUJITA Tomonori | 99c84db | 2008-02-04 22:28:17 -0800 | [diff] [blame] | 1636 | dma_set_seg_boundary(dev, shost->dma_boundary); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1637 | |
FUJITA Tomonori | 860ac56 | 2008-02-04 22:28:05 -0800 | [diff] [blame] | 1638 | blk_queue_max_segment_size(q, dma_get_max_seg_size(dev)); |
| 1639 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1640 | if (!shost->use_clustering) |
Martin K. Petersen | e692cb6 | 2010-12-01 19:41:49 +0100 | [diff] [blame] | 1641 | q->limits.cluster = 0; |
James Bottomley | 465ff31 | 2008-01-01 10:00:10 -0600 | [diff] [blame] | 1642 | |
| 1643 | /* |
| 1644 | * set a reasonable default alignment on word boundaries: the |
| 1645 | * host and device may alter it using |
| 1646 | * blk_queue_update_dma_alignment() later. |
| 1647 | */ |
| 1648 | blk_queue_dma_alignment(q, 0x03); |
| 1649 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1650 | return q; |
| 1651 | } |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 1652 | EXPORT_SYMBOL(__scsi_alloc_queue); |
| 1653 | |
| 1654 | struct request_queue *scsi_alloc_queue(struct scsi_device *sdev) |
| 1655 | { |
| 1656 | struct request_queue *q; |
| 1657 | |
| 1658 | q = __scsi_alloc_queue(sdev->host, scsi_request_fn); |
| 1659 | if (!q) |
| 1660 | return NULL; |
| 1661 | |
| 1662 | blk_queue_prep_rq(q, scsi_prep_fn); |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 1663 | blk_queue_softirq_done(q, scsi_softirq_done); |
Jens Axboe | 242f9dc | 2008-09-14 05:55:09 -0700 | [diff] [blame] | 1664 | blk_queue_rq_timed_out(q, scsi_times_out); |
Kiyoshi Ueda | 6c5121b | 2008-10-04 14:11:35 -0400 | [diff] [blame] | 1665 | blk_queue_lld_busy(q, scsi_lld_busy); |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 1666 | return q; |
| 1667 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1668 | |
| 1669 | void scsi_free_queue(struct request_queue *q) |
| 1670 | { |
| 1671 | blk_cleanup_queue(q); |
| 1672 | } |
| 1673 | |
| 1674 | /* |
| 1675 | * Function: scsi_block_requests() |
| 1676 | * |
| 1677 | * Purpose: Utility function used by low-level drivers to prevent further |
| 1678 | * commands from being queued to the device. |
| 1679 | * |
| 1680 | * Arguments: shost - Host in question |
| 1681 | * |
| 1682 | * Returns: Nothing |
| 1683 | * |
| 1684 | * Lock status: No locks are assumed held. |
| 1685 | * |
| 1686 | * Notes: There is no timer nor any other means by which the requests |
| 1687 | * get unblocked other than the low-level driver calling |
| 1688 | * scsi_unblock_requests(). |
| 1689 | */ |
| 1690 | void scsi_block_requests(struct Scsi_Host *shost) |
| 1691 | { |
| 1692 | shost->host_self_blocked = 1; |
| 1693 | } |
| 1694 | EXPORT_SYMBOL(scsi_block_requests); |
| 1695 | |
| 1696 | /* |
| 1697 | * Function: scsi_unblock_requests() |
| 1698 | * |
| 1699 | * Purpose: Utility function used by low-level drivers to allow further |
| 1700 | * commands from being queued to the device. |
| 1701 | * |
| 1702 | * Arguments: shost - Host in question |
| 1703 | * |
| 1704 | * Returns: Nothing |
| 1705 | * |
| 1706 | * Lock status: No locks are assumed held. |
| 1707 | * |
| 1708 | * Notes: There is no timer nor any other means by which the requests |
| 1709 | * get unblocked other than the low-level driver calling |
| 1710 | * scsi_unblock_requests(). |
| 1711 | * |
| 1712 | * This is done as an API function so that changes to the |
| 1713 | * internals of the scsi mid-layer won't require wholesale |
| 1714 | * changes to drivers that use this feature. |
| 1715 | */ |
| 1716 | void scsi_unblock_requests(struct Scsi_Host *shost) |
| 1717 | { |
| 1718 | shost->host_self_blocked = 0; |
| 1719 | scsi_run_host_queues(shost); |
| 1720 | } |
| 1721 | EXPORT_SYMBOL(scsi_unblock_requests); |
| 1722 | |
| 1723 | int __init scsi_init_queue(void) |
| 1724 | { |
| 1725 | int i; |
| 1726 | |
Martin K. Petersen | 6362abd | 2008-06-05 23:30:03 -0400 | [diff] [blame] | 1727 | scsi_sdb_cache = kmem_cache_create("scsi_data_buffer", |
| 1728 | sizeof(struct scsi_data_buffer), |
| 1729 | 0, 0, NULL); |
| 1730 | if (!scsi_sdb_cache) { |
| 1731 | printk(KERN_ERR "SCSI: can't init scsi sdb cache\n"); |
FUJITA Tomonori | f078727 | 2008-12-14 01:23:45 +0900 | [diff] [blame] | 1732 | return -ENOMEM; |
Boaz Harrosh | 6f9a35e | 2007-12-13 13:50:53 +0200 | [diff] [blame] | 1733 | } |
| 1734 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1735 | for (i = 0; i < SG_MEMPOOL_NR; i++) { |
| 1736 | struct scsi_host_sg_pool *sgp = scsi_sg_pools + i; |
| 1737 | int size = sgp->size * sizeof(struct scatterlist); |
| 1738 | |
| 1739 | sgp->slab = kmem_cache_create(sgp->name, size, 0, |
Paul Mundt | 20c2df8 | 2007-07-20 10:11:58 +0900 | [diff] [blame] | 1740 | SLAB_HWCACHE_ALIGN, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1741 | if (!sgp->slab) { |
| 1742 | printk(KERN_ERR "SCSI: can't init sg slab %s\n", |
| 1743 | sgp->name); |
Martin K. Petersen | 6362abd | 2008-06-05 23:30:03 -0400 | [diff] [blame] | 1744 | goto cleanup_sdb; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1745 | } |
| 1746 | |
Matthew Dobson | 93d2341 | 2006-03-26 01:37:50 -0800 | [diff] [blame] | 1747 | sgp->pool = mempool_create_slab_pool(SG_MEMPOOL_SIZE, |
| 1748 | sgp->slab); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1749 | if (!sgp->pool) { |
| 1750 | printk(KERN_ERR "SCSI: can't init sg mempool %s\n", |
| 1751 | sgp->name); |
Martin K. Petersen | 6362abd | 2008-06-05 23:30:03 -0400 | [diff] [blame] | 1752 | goto cleanup_sdb; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1753 | } |
| 1754 | } |
| 1755 | |
| 1756 | return 0; |
FUJITA Tomonori | 3d9dd6e | 2008-01-25 23:25:14 +0900 | [diff] [blame] | 1757 | |
Martin K. Petersen | 6362abd | 2008-06-05 23:30:03 -0400 | [diff] [blame] | 1758 | cleanup_sdb: |
FUJITA Tomonori | 3d9dd6e | 2008-01-25 23:25:14 +0900 | [diff] [blame] | 1759 | for (i = 0; i < SG_MEMPOOL_NR; i++) { |
| 1760 | struct scsi_host_sg_pool *sgp = scsi_sg_pools + i; |
| 1761 | if (sgp->pool) |
| 1762 | mempool_destroy(sgp->pool); |
| 1763 | if (sgp->slab) |
| 1764 | kmem_cache_destroy(sgp->slab); |
| 1765 | } |
Martin K. Petersen | 6362abd | 2008-06-05 23:30:03 -0400 | [diff] [blame] | 1766 | kmem_cache_destroy(scsi_sdb_cache); |
FUJITA Tomonori | 3d9dd6e | 2008-01-25 23:25:14 +0900 | [diff] [blame] | 1767 | |
| 1768 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1769 | } |
| 1770 | |
| 1771 | void scsi_exit_queue(void) |
| 1772 | { |
| 1773 | int i; |
| 1774 | |
Martin K. Petersen | 6362abd | 2008-06-05 23:30:03 -0400 | [diff] [blame] | 1775 | kmem_cache_destroy(scsi_sdb_cache); |
Mike Christie | aa7b5cd | 2005-11-11 05:31:41 -0600 | [diff] [blame] | 1776 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1777 | for (i = 0; i < SG_MEMPOOL_NR; i++) { |
| 1778 | struct scsi_host_sg_pool *sgp = scsi_sg_pools + i; |
| 1779 | mempool_destroy(sgp->pool); |
| 1780 | kmem_cache_destroy(sgp->slab); |
| 1781 | } |
| 1782 | } |
James Bottomley | 5baba83 | 2006-03-18 14:10:35 -0600 | [diff] [blame] | 1783 | |
| 1784 | /** |
| 1785 | * scsi_mode_select - issue a mode select |
| 1786 | * @sdev: SCSI device to be queried |
| 1787 | * @pf: Page format bit (1 == standard, 0 == vendor specific) |
| 1788 | * @sp: Save page bit (0 == don't save, 1 == save) |
| 1789 | * @modepage: mode page being requested |
| 1790 | * @buffer: request buffer (may not be smaller than eight bytes) |
| 1791 | * @len: length of request buffer. |
| 1792 | * @timeout: command timeout |
| 1793 | * @retries: number of retries before failing |
| 1794 | * @data: returns a structure abstracting the mode header data |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1795 | * @sshdr: place to put sense data (or NULL if no sense to be collected). |
James Bottomley | 5baba83 | 2006-03-18 14:10:35 -0600 | [diff] [blame] | 1796 | * must be SCSI_SENSE_BUFFERSIZE big. |
| 1797 | * |
| 1798 | * Returns zero if successful; negative error number or scsi |
| 1799 | * status on error |
| 1800 | * |
| 1801 | */ |
| 1802 | int |
| 1803 | scsi_mode_select(struct scsi_device *sdev, int pf, int sp, int modepage, |
| 1804 | unsigned char *buffer, int len, int timeout, int retries, |
| 1805 | struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr) |
| 1806 | { |
| 1807 | unsigned char cmd[10]; |
| 1808 | unsigned char *real_buffer; |
| 1809 | int ret; |
| 1810 | |
| 1811 | memset(cmd, 0, sizeof(cmd)); |
| 1812 | cmd[1] = (pf ? 0x10 : 0) | (sp ? 0x01 : 0); |
| 1813 | |
| 1814 | if (sdev->use_10_for_ms) { |
| 1815 | if (len > 65535) |
| 1816 | return -EINVAL; |
| 1817 | real_buffer = kmalloc(8 + len, GFP_KERNEL); |
| 1818 | if (!real_buffer) |
| 1819 | return -ENOMEM; |
| 1820 | memcpy(real_buffer + 8, buffer, len); |
| 1821 | len += 8; |
| 1822 | real_buffer[0] = 0; |
| 1823 | real_buffer[1] = 0; |
| 1824 | real_buffer[2] = data->medium_type; |
| 1825 | real_buffer[3] = data->device_specific; |
| 1826 | real_buffer[4] = data->longlba ? 0x01 : 0; |
| 1827 | real_buffer[5] = 0; |
| 1828 | real_buffer[6] = data->block_descriptor_length >> 8; |
| 1829 | real_buffer[7] = data->block_descriptor_length; |
| 1830 | |
| 1831 | cmd[0] = MODE_SELECT_10; |
| 1832 | cmd[7] = len >> 8; |
| 1833 | cmd[8] = len; |
| 1834 | } else { |
| 1835 | if (len > 255 || data->block_descriptor_length > 255 || |
| 1836 | data->longlba) |
| 1837 | return -EINVAL; |
| 1838 | |
| 1839 | real_buffer = kmalloc(4 + len, GFP_KERNEL); |
| 1840 | if (!real_buffer) |
| 1841 | return -ENOMEM; |
| 1842 | memcpy(real_buffer + 4, buffer, len); |
| 1843 | len += 4; |
| 1844 | real_buffer[0] = 0; |
| 1845 | real_buffer[1] = data->medium_type; |
| 1846 | real_buffer[2] = data->device_specific; |
| 1847 | real_buffer[3] = data->block_descriptor_length; |
| 1848 | |
| 1849 | |
| 1850 | cmd[0] = MODE_SELECT; |
| 1851 | cmd[4] = len; |
| 1852 | } |
| 1853 | |
| 1854 | ret = scsi_execute_req(sdev, cmd, DMA_TO_DEVICE, real_buffer, len, |
FUJITA Tomonori | f4f4e47 | 2008-12-04 14:24:39 +0900 | [diff] [blame] | 1855 | sshdr, timeout, retries, NULL); |
James Bottomley | 5baba83 | 2006-03-18 14:10:35 -0600 | [diff] [blame] | 1856 | kfree(real_buffer); |
| 1857 | return ret; |
| 1858 | } |
| 1859 | EXPORT_SYMBOL_GPL(scsi_mode_select); |
| 1860 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1861 | /** |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1862 | * scsi_mode_sense - issue a mode sense, falling back from 10 to six bytes if necessary. |
James Bottomley | 1cf7269 | 2005-08-28 11:27:01 -0500 | [diff] [blame] | 1863 | * @sdev: SCSI device to be queried |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1864 | * @dbd: set if mode sense will allow block descriptors to be returned |
| 1865 | * @modepage: mode page being requested |
| 1866 | * @buffer: request buffer (may not be smaller than eight bytes) |
| 1867 | * @len: length of request buffer. |
| 1868 | * @timeout: command timeout |
| 1869 | * @retries: number of retries before failing |
| 1870 | * @data: returns a structure abstracting the mode header data |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1871 | * @sshdr: place to put sense data (or NULL if no sense to be collected). |
James Bottomley | 1cf7269 | 2005-08-28 11:27:01 -0500 | [diff] [blame] | 1872 | * must be SCSI_SENSE_BUFFERSIZE big. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1873 | * |
| 1874 | * Returns zero if unsuccessful, or the header offset (either 4 |
| 1875 | * or 8 depending on whether a six or ten byte command was |
| 1876 | * issued) if successful. |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1877 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1878 | int |
James Bottomley | 1cf7269 | 2005-08-28 11:27:01 -0500 | [diff] [blame] | 1879 | scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1880 | unsigned char *buffer, int len, int timeout, int retries, |
James Bottomley | 5baba83 | 2006-03-18 14:10:35 -0600 | [diff] [blame] | 1881 | struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr) |
| 1882 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1883 | unsigned char cmd[12]; |
| 1884 | int use_10_for_ms; |
| 1885 | int header_length; |
James Bottomley | 1cf7269 | 2005-08-28 11:27:01 -0500 | [diff] [blame] | 1886 | int result; |
James Bottomley | ea73a9f | 2005-08-28 11:33:52 -0500 | [diff] [blame] | 1887 | struct scsi_sense_hdr my_sshdr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1888 | |
| 1889 | memset(data, 0, sizeof(*data)); |
| 1890 | memset(&cmd[0], 0, 12); |
| 1891 | cmd[1] = dbd & 0x18; /* allows DBD and LLBA bits */ |
| 1892 | cmd[2] = modepage; |
| 1893 | |
James Bottomley | ea73a9f | 2005-08-28 11:33:52 -0500 | [diff] [blame] | 1894 | /* caller might not be interested in sense, but we need it */ |
| 1895 | if (!sshdr) |
| 1896 | sshdr = &my_sshdr; |
| 1897 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1898 | retry: |
James Bottomley | 1cf7269 | 2005-08-28 11:27:01 -0500 | [diff] [blame] | 1899 | use_10_for_ms = sdev->use_10_for_ms; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1900 | |
| 1901 | if (use_10_for_ms) { |
| 1902 | if (len < 8) |
| 1903 | len = 8; |
| 1904 | |
| 1905 | cmd[0] = MODE_SENSE_10; |
| 1906 | cmd[8] = len; |
| 1907 | header_length = 8; |
| 1908 | } else { |
| 1909 | if (len < 4) |
| 1910 | len = 4; |
| 1911 | |
| 1912 | cmd[0] = MODE_SENSE; |
| 1913 | cmd[4] = len; |
| 1914 | header_length = 4; |
| 1915 | } |
| 1916 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1917 | memset(buffer, 0, len); |
| 1918 | |
James Bottomley | 1cf7269 | 2005-08-28 11:27:01 -0500 | [diff] [blame] | 1919 | result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer, len, |
FUJITA Tomonori | f4f4e47 | 2008-12-04 14:24:39 +0900 | [diff] [blame] | 1920 | sshdr, timeout, retries, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1921 | |
| 1922 | /* This code looks awful: what it's doing is making sure an |
| 1923 | * ILLEGAL REQUEST sense return identifies the actual command |
| 1924 | * byte as the problem. MODE_SENSE commands can return |
| 1925 | * ILLEGAL REQUEST if the code page isn't supported */ |
| 1926 | |
James Bottomley | 1cf7269 | 2005-08-28 11:27:01 -0500 | [diff] [blame] | 1927 | if (use_10_for_ms && !scsi_status_is_good(result) && |
| 1928 | (driver_byte(result) & DRIVER_SENSE)) { |
James Bottomley | ea73a9f | 2005-08-28 11:33:52 -0500 | [diff] [blame] | 1929 | if (scsi_sense_valid(sshdr)) { |
| 1930 | if ((sshdr->sense_key == ILLEGAL_REQUEST) && |
| 1931 | (sshdr->asc == 0x20) && (sshdr->ascq == 0)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1932 | /* |
| 1933 | * Invalid command operation code |
| 1934 | */ |
James Bottomley | 1cf7269 | 2005-08-28 11:27:01 -0500 | [diff] [blame] | 1935 | sdev->use_10_for_ms = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1936 | goto retry; |
| 1937 | } |
| 1938 | } |
| 1939 | } |
| 1940 | |
James Bottomley | 1cf7269 | 2005-08-28 11:27:01 -0500 | [diff] [blame] | 1941 | if(scsi_status_is_good(result)) { |
Al Viro | 6d73c85 | 2006-02-23 02:03:16 +0100 | [diff] [blame] | 1942 | if (unlikely(buffer[0] == 0x86 && buffer[1] == 0x0b && |
| 1943 | (modepage == 6 || modepage == 8))) { |
| 1944 | /* Initio breakage? */ |
| 1945 | header_length = 0; |
| 1946 | data->length = 13; |
| 1947 | data->medium_type = 0; |
| 1948 | data->device_specific = 0; |
| 1949 | data->longlba = 0; |
| 1950 | data->block_descriptor_length = 0; |
| 1951 | } else if(use_10_for_ms) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1952 | data->length = buffer[0]*256 + buffer[1] + 2; |
| 1953 | data->medium_type = buffer[2]; |
| 1954 | data->device_specific = buffer[3]; |
| 1955 | data->longlba = buffer[4] & 0x01; |
| 1956 | data->block_descriptor_length = buffer[6]*256 |
| 1957 | + buffer[7]; |
| 1958 | } else { |
| 1959 | data->length = buffer[0] + 1; |
| 1960 | data->medium_type = buffer[1]; |
| 1961 | data->device_specific = buffer[2]; |
| 1962 | data->block_descriptor_length = buffer[3]; |
| 1963 | } |
Al Viro | 6d73c85 | 2006-02-23 02:03:16 +0100 | [diff] [blame] | 1964 | data->header_length = header_length; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1965 | } |
| 1966 | |
James Bottomley | 1cf7269 | 2005-08-28 11:27:01 -0500 | [diff] [blame] | 1967 | return result; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1968 | } |
| 1969 | EXPORT_SYMBOL(scsi_mode_sense); |
| 1970 | |
James Bottomley | 001aac2 | 2007-12-02 19:10:40 +0200 | [diff] [blame] | 1971 | /** |
| 1972 | * scsi_test_unit_ready - test if unit is ready |
| 1973 | * @sdev: scsi device to change the state of. |
| 1974 | * @timeout: command timeout |
| 1975 | * @retries: number of retries before failing |
| 1976 | * @sshdr_external: Optional pointer to struct scsi_sense_hdr for |
| 1977 | * returning sense. Make sure that this is cleared before passing |
| 1978 | * in. |
| 1979 | * |
| 1980 | * Returns zero if unsuccessful or an error if TUR failed. For |
| 1981 | * removable media, a return of NOT_READY or UNIT_ATTENTION is |
| 1982 | * translated to success, with the ->changed flag updated. |
| 1983 | **/ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1984 | int |
James Bottomley | 001aac2 | 2007-12-02 19:10:40 +0200 | [diff] [blame] | 1985 | scsi_test_unit_ready(struct scsi_device *sdev, int timeout, int retries, |
| 1986 | struct scsi_sense_hdr *sshdr_external) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1987 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1988 | char cmd[] = { |
| 1989 | TEST_UNIT_READY, 0, 0, 0, 0, 0, |
| 1990 | }; |
James Bottomley | 001aac2 | 2007-12-02 19:10:40 +0200 | [diff] [blame] | 1991 | struct scsi_sense_hdr *sshdr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1992 | int result; |
James Bottomley | 001aac2 | 2007-12-02 19:10:40 +0200 | [diff] [blame] | 1993 | |
| 1994 | if (!sshdr_external) |
| 1995 | sshdr = kzalloc(sizeof(*sshdr), GFP_KERNEL); |
| 1996 | else |
| 1997 | sshdr = sshdr_external; |
| 1998 | |
| 1999 | /* try to eat the UNIT_ATTENTION if there are enough retries */ |
| 2000 | do { |
| 2001 | result = scsi_execute_req(sdev, cmd, DMA_NONE, NULL, 0, sshdr, |
FUJITA Tomonori | f4f4e47 | 2008-12-04 14:24:39 +0900 | [diff] [blame] | 2002 | timeout, retries, NULL); |
James Bottomley | 32c356d | 2008-08-20 00:58:13 +0200 | [diff] [blame] | 2003 | if (sdev->removable && scsi_sense_valid(sshdr) && |
| 2004 | sshdr->sense_key == UNIT_ATTENTION) |
| 2005 | sdev->changed = 1; |
| 2006 | } while (scsi_sense_valid(sshdr) && |
| 2007 | sshdr->sense_key == UNIT_ATTENTION && --retries); |
James Bottomley | 001aac2 | 2007-12-02 19:10:40 +0200 | [diff] [blame] | 2008 | |
| 2009 | if (!sshdr) |
| 2010 | /* could not allocate sense buffer, so can't process it */ |
| 2011 | return result; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2012 | |
James Bottomley | 32c356d | 2008-08-20 00:58:13 +0200 | [diff] [blame] | 2013 | if (sdev->removable && scsi_sense_valid(sshdr) && |
| 2014 | (sshdr->sense_key == UNIT_ATTENTION || |
| 2015 | sshdr->sense_key == NOT_READY)) { |
| 2016 | sdev->changed = 1; |
| 2017 | result = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2018 | } |
James Bottomley | 001aac2 | 2007-12-02 19:10:40 +0200 | [diff] [blame] | 2019 | if (!sshdr_external) |
| 2020 | kfree(sshdr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2021 | return result; |
| 2022 | } |
| 2023 | EXPORT_SYMBOL(scsi_test_unit_ready); |
| 2024 | |
| 2025 | /** |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 2026 | * scsi_device_set_state - Take the given device through the device state model. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2027 | * @sdev: scsi device to change the state of. |
| 2028 | * @state: state to change to. |
| 2029 | * |
| 2030 | * Returns zero if unsuccessful or an error if the requested |
| 2031 | * transition is illegal. |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 2032 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2033 | int |
| 2034 | scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state) |
| 2035 | { |
| 2036 | enum scsi_device_state oldstate = sdev->sdev_state; |
| 2037 | |
| 2038 | if (state == oldstate) |
| 2039 | return 0; |
| 2040 | |
| 2041 | switch (state) { |
| 2042 | case SDEV_CREATED: |
James Bottomley | 6f4267e | 2008-08-22 16:53:31 -0500 | [diff] [blame] | 2043 | switch (oldstate) { |
| 2044 | case SDEV_CREATED_BLOCK: |
| 2045 | break; |
| 2046 | default: |
| 2047 | goto illegal; |
| 2048 | } |
| 2049 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2050 | |
| 2051 | case SDEV_RUNNING: |
| 2052 | switch (oldstate) { |
| 2053 | case SDEV_CREATED: |
| 2054 | case SDEV_OFFLINE: |
| 2055 | case SDEV_QUIESCE: |
| 2056 | case SDEV_BLOCK: |
| 2057 | break; |
| 2058 | default: |
| 2059 | goto illegal; |
| 2060 | } |
| 2061 | break; |
| 2062 | |
| 2063 | case SDEV_QUIESCE: |
| 2064 | switch (oldstate) { |
| 2065 | case SDEV_RUNNING: |
| 2066 | case SDEV_OFFLINE: |
| 2067 | break; |
| 2068 | default: |
| 2069 | goto illegal; |
| 2070 | } |
| 2071 | break; |
| 2072 | |
| 2073 | case SDEV_OFFLINE: |
| 2074 | switch (oldstate) { |
| 2075 | case SDEV_CREATED: |
| 2076 | case SDEV_RUNNING: |
| 2077 | case SDEV_QUIESCE: |
| 2078 | case SDEV_BLOCK: |
| 2079 | break; |
| 2080 | default: |
| 2081 | goto illegal; |
| 2082 | } |
| 2083 | break; |
| 2084 | |
| 2085 | case SDEV_BLOCK: |
| 2086 | switch (oldstate) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2087 | case SDEV_RUNNING: |
James Bottomley | 6f4267e | 2008-08-22 16:53:31 -0500 | [diff] [blame] | 2088 | case SDEV_CREATED_BLOCK: |
| 2089 | break; |
| 2090 | default: |
| 2091 | goto illegal; |
| 2092 | } |
| 2093 | break; |
| 2094 | |
| 2095 | case SDEV_CREATED_BLOCK: |
| 2096 | switch (oldstate) { |
| 2097 | case SDEV_CREATED: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2098 | break; |
| 2099 | default: |
| 2100 | goto illegal; |
| 2101 | } |
| 2102 | break; |
| 2103 | |
| 2104 | case SDEV_CANCEL: |
| 2105 | switch (oldstate) { |
| 2106 | case SDEV_CREATED: |
| 2107 | case SDEV_RUNNING: |
Alan Stern | 9ea7290 | 2006-06-23 14:25:34 -0400 | [diff] [blame] | 2108 | case SDEV_QUIESCE: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2109 | case SDEV_OFFLINE: |
| 2110 | case SDEV_BLOCK: |
| 2111 | break; |
| 2112 | default: |
| 2113 | goto illegal; |
| 2114 | } |
| 2115 | break; |
| 2116 | |
| 2117 | case SDEV_DEL: |
| 2118 | switch (oldstate) { |
Brian King | 309bd27 | 2006-06-27 11:10:43 -0500 | [diff] [blame] | 2119 | case SDEV_CREATED: |
| 2120 | case SDEV_RUNNING: |
| 2121 | case SDEV_OFFLINE: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2122 | case SDEV_CANCEL: |
| 2123 | break; |
| 2124 | default: |
| 2125 | goto illegal; |
| 2126 | } |
| 2127 | break; |
| 2128 | |
| 2129 | } |
| 2130 | sdev->sdev_state = state; |
| 2131 | return 0; |
| 2132 | |
| 2133 | illegal: |
| 2134 | SCSI_LOG_ERROR_RECOVERY(1, |
James Bottomley | 9ccfc75 | 2005-10-02 11:45:08 -0500 | [diff] [blame] | 2135 | sdev_printk(KERN_ERR, sdev, |
| 2136 | "Illegal state transition %s->%s\n", |
| 2137 | scsi_device_state_name(oldstate), |
| 2138 | scsi_device_state_name(state)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2139 | ); |
| 2140 | return -EINVAL; |
| 2141 | } |
| 2142 | EXPORT_SYMBOL(scsi_device_set_state); |
| 2143 | |
| 2144 | /** |
Jeff Garzik | a341cd0 | 2007-10-29 17:15:22 -0400 | [diff] [blame] | 2145 | * sdev_evt_emit - emit a single SCSI device uevent |
| 2146 | * @sdev: associated SCSI device |
| 2147 | * @evt: event to emit |
| 2148 | * |
| 2149 | * Send a single uevent (scsi_event) to the associated scsi_device. |
| 2150 | */ |
| 2151 | static void scsi_evt_emit(struct scsi_device *sdev, struct scsi_event *evt) |
| 2152 | { |
| 2153 | int idx = 0; |
| 2154 | char *envp[3]; |
| 2155 | |
| 2156 | switch (evt->evt_type) { |
| 2157 | case SDEV_EVT_MEDIA_CHANGE: |
| 2158 | envp[idx++] = "SDEV_MEDIA_CHANGE=1"; |
| 2159 | break; |
| 2160 | |
| 2161 | default: |
| 2162 | /* do nothing */ |
| 2163 | break; |
| 2164 | } |
| 2165 | |
| 2166 | envp[idx++] = NULL; |
| 2167 | |
| 2168 | kobject_uevent_env(&sdev->sdev_gendev.kobj, KOBJ_CHANGE, envp); |
| 2169 | } |
| 2170 | |
| 2171 | /** |
| 2172 | * sdev_evt_thread - send a uevent for each scsi event |
| 2173 | * @work: work struct for scsi_device |
| 2174 | * |
| 2175 | * Dispatch queued events to their associated scsi_device kobjects |
| 2176 | * as uevents. |
| 2177 | */ |
| 2178 | void scsi_evt_thread(struct work_struct *work) |
| 2179 | { |
| 2180 | struct scsi_device *sdev; |
| 2181 | LIST_HEAD(event_list); |
| 2182 | |
| 2183 | sdev = container_of(work, struct scsi_device, event_work); |
| 2184 | |
| 2185 | while (1) { |
| 2186 | struct scsi_event *evt; |
| 2187 | struct list_head *this, *tmp; |
| 2188 | unsigned long flags; |
| 2189 | |
| 2190 | spin_lock_irqsave(&sdev->list_lock, flags); |
| 2191 | list_splice_init(&sdev->event_list, &event_list); |
| 2192 | spin_unlock_irqrestore(&sdev->list_lock, flags); |
| 2193 | |
| 2194 | if (list_empty(&event_list)) |
| 2195 | break; |
| 2196 | |
| 2197 | list_for_each_safe(this, tmp, &event_list) { |
| 2198 | evt = list_entry(this, struct scsi_event, node); |
| 2199 | list_del(&evt->node); |
| 2200 | scsi_evt_emit(sdev, evt); |
| 2201 | kfree(evt); |
| 2202 | } |
| 2203 | } |
| 2204 | } |
| 2205 | |
| 2206 | /** |
| 2207 | * sdev_evt_send - send asserted event to uevent thread |
| 2208 | * @sdev: scsi_device event occurred on |
| 2209 | * @evt: event to send |
| 2210 | * |
| 2211 | * Assert scsi device event asynchronously. |
| 2212 | */ |
| 2213 | void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt) |
| 2214 | { |
| 2215 | unsigned long flags; |
| 2216 | |
Kay Sievers | 4d1566e | 2008-03-19 13:04:47 +0100 | [diff] [blame] | 2217 | #if 0 |
| 2218 | /* FIXME: currently this check eliminates all media change events |
| 2219 | * for polled devices. Need to update to discriminate between AN |
| 2220 | * and polled events */ |
Jeff Garzik | a341cd0 | 2007-10-29 17:15:22 -0400 | [diff] [blame] | 2221 | if (!test_bit(evt->evt_type, sdev->supported_events)) { |
| 2222 | kfree(evt); |
| 2223 | return; |
| 2224 | } |
Kay Sievers | 4d1566e | 2008-03-19 13:04:47 +0100 | [diff] [blame] | 2225 | #endif |
Jeff Garzik | a341cd0 | 2007-10-29 17:15:22 -0400 | [diff] [blame] | 2226 | |
| 2227 | spin_lock_irqsave(&sdev->list_lock, flags); |
| 2228 | list_add_tail(&evt->node, &sdev->event_list); |
| 2229 | schedule_work(&sdev->event_work); |
| 2230 | spin_unlock_irqrestore(&sdev->list_lock, flags); |
| 2231 | } |
| 2232 | EXPORT_SYMBOL_GPL(sdev_evt_send); |
| 2233 | |
| 2234 | /** |
| 2235 | * sdev_evt_alloc - allocate a new scsi event |
| 2236 | * @evt_type: type of event to allocate |
| 2237 | * @gfpflags: GFP flags for allocation |
| 2238 | * |
| 2239 | * Allocates and returns a new scsi_event. |
| 2240 | */ |
| 2241 | struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type, |
| 2242 | gfp_t gfpflags) |
| 2243 | { |
| 2244 | struct scsi_event *evt = kzalloc(sizeof(struct scsi_event), gfpflags); |
| 2245 | if (!evt) |
| 2246 | return NULL; |
| 2247 | |
| 2248 | evt->evt_type = evt_type; |
| 2249 | INIT_LIST_HEAD(&evt->node); |
| 2250 | |
| 2251 | /* evt_type-specific initialization, if any */ |
| 2252 | switch (evt_type) { |
| 2253 | case SDEV_EVT_MEDIA_CHANGE: |
| 2254 | default: |
| 2255 | /* do nothing */ |
| 2256 | break; |
| 2257 | } |
| 2258 | |
| 2259 | return evt; |
| 2260 | } |
| 2261 | EXPORT_SYMBOL_GPL(sdev_evt_alloc); |
| 2262 | |
| 2263 | /** |
| 2264 | * sdev_evt_send_simple - send asserted event to uevent thread |
| 2265 | * @sdev: scsi_device event occurred on |
| 2266 | * @evt_type: type of event to send |
| 2267 | * @gfpflags: GFP flags for allocation |
| 2268 | * |
| 2269 | * Assert scsi device event asynchronously, given an event type. |
| 2270 | */ |
| 2271 | void sdev_evt_send_simple(struct scsi_device *sdev, |
| 2272 | enum scsi_device_event evt_type, gfp_t gfpflags) |
| 2273 | { |
| 2274 | struct scsi_event *evt = sdev_evt_alloc(evt_type, gfpflags); |
| 2275 | if (!evt) { |
| 2276 | sdev_printk(KERN_ERR, sdev, "event %d eaten due to OOM\n", |
| 2277 | evt_type); |
| 2278 | return; |
| 2279 | } |
| 2280 | |
| 2281 | sdev_evt_send(sdev, evt); |
| 2282 | } |
| 2283 | EXPORT_SYMBOL_GPL(sdev_evt_send_simple); |
| 2284 | |
| 2285 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2286 | * scsi_device_quiesce - Block user issued commands. |
| 2287 | * @sdev: scsi device to quiesce. |
| 2288 | * |
| 2289 | * This works by trying to transition to the SDEV_QUIESCE state |
| 2290 | * (which must be a legal transition). When the device is in this |
| 2291 | * state, only special requests will be accepted, all others will |
| 2292 | * be deferred. Since special requests may also be requeued requests, |
| 2293 | * a successful return doesn't guarantee the device will be |
| 2294 | * totally quiescent. |
| 2295 | * |
| 2296 | * Must be called with user context, may sleep. |
| 2297 | * |
| 2298 | * Returns zero if unsuccessful or an error if not. |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 2299 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2300 | int |
| 2301 | scsi_device_quiesce(struct scsi_device *sdev) |
| 2302 | { |
| 2303 | int err = scsi_device_set_state(sdev, SDEV_QUIESCE); |
| 2304 | if (err) |
| 2305 | return err; |
| 2306 | |
| 2307 | scsi_run_queue(sdev->request_queue); |
| 2308 | while (sdev->device_busy) { |
| 2309 | msleep_interruptible(200); |
| 2310 | scsi_run_queue(sdev->request_queue); |
| 2311 | } |
| 2312 | return 0; |
| 2313 | } |
| 2314 | EXPORT_SYMBOL(scsi_device_quiesce); |
| 2315 | |
| 2316 | /** |
| 2317 | * scsi_device_resume - Restart user issued commands to a quiesced device. |
| 2318 | * @sdev: scsi device to resume. |
| 2319 | * |
| 2320 | * Moves the device from quiesced back to running and restarts the |
| 2321 | * queues. |
| 2322 | * |
| 2323 | * Must be called with user context, may sleep. |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 2324 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2325 | void |
| 2326 | scsi_device_resume(struct scsi_device *sdev) |
| 2327 | { |
| 2328 | if(scsi_device_set_state(sdev, SDEV_RUNNING)) |
| 2329 | return; |
| 2330 | scsi_run_queue(sdev->request_queue); |
| 2331 | } |
| 2332 | EXPORT_SYMBOL(scsi_device_resume); |
| 2333 | |
| 2334 | static void |
| 2335 | device_quiesce_fn(struct scsi_device *sdev, void *data) |
| 2336 | { |
| 2337 | scsi_device_quiesce(sdev); |
| 2338 | } |
| 2339 | |
| 2340 | void |
| 2341 | scsi_target_quiesce(struct scsi_target *starget) |
| 2342 | { |
| 2343 | starget_for_each_device(starget, NULL, device_quiesce_fn); |
| 2344 | } |
| 2345 | EXPORT_SYMBOL(scsi_target_quiesce); |
| 2346 | |
| 2347 | static void |
| 2348 | device_resume_fn(struct scsi_device *sdev, void *data) |
| 2349 | { |
| 2350 | scsi_device_resume(sdev); |
| 2351 | } |
| 2352 | |
| 2353 | void |
| 2354 | scsi_target_resume(struct scsi_target *starget) |
| 2355 | { |
| 2356 | starget_for_each_device(starget, NULL, device_resume_fn); |
| 2357 | } |
| 2358 | EXPORT_SYMBOL(scsi_target_resume); |
| 2359 | |
| 2360 | /** |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 2361 | * scsi_internal_device_block - internal function to put a device temporarily into the SDEV_BLOCK state |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2362 | * @sdev: device to block |
| 2363 | * |
| 2364 | * Block request made by scsi lld's to temporarily stop all |
| 2365 | * scsi commands on the specified device. Called from interrupt |
| 2366 | * or normal process context. |
| 2367 | * |
| 2368 | * Returns zero if successful or error if not |
| 2369 | * |
| 2370 | * Notes: |
| 2371 | * This routine transitions the device to the SDEV_BLOCK state |
| 2372 | * (which must be a legal transition). When the device is in this |
| 2373 | * state, all commands are deferred until the scsi lld reenables |
| 2374 | * the device with scsi_device_unblock or device_block_tmo fires. |
| 2375 | * This routine assumes the host_lock is held on entry. |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 2376 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2377 | int |
| 2378 | scsi_internal_device_block(struct scsi_device *sdev) |
| 2379 | { |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 2380 | struct request_queue *q = sdev->request_queue; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2381 | unsigned long flags; |
| 2382 | int err = 0; |
| 2383 | |
| 2384 | err = scsi_device_set_state(sdev, SDEV_BLOCK); |
James Bottomley | 6f4267e | 2008-08-22 16:53:31 -0500 | [diff] [blame] | 2385 | if (err) { |
| 2386 | err = scsi_device_set_state(sdev, SDEV_CREATED_BLOCK); |
| 2387 | |
| 2388 | if (err) |
| 2389 | return err; |
| 2390 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2391 | |
| 2392 | /* |
| 2393 | * The device has transitioned to SDEV_BLOCK. Stop the |
| 2394 | * block layer from calling the midlayer with this device's |
| 2395 | * request queue. |
| 2396 | */ |
| 2397 | spin_lock_irqsave(q->queue_lock, flags); |
| 2398 | blk_stop_queue(q); |
| 2399 | spin_unlock_irqrestore(q->queue_lock, flags); |
| 2400 | |
| 2401 | return 0; |
| 2402 | } |
| 2403 | EXPORT_SYMBOL_GPL(scsi_internal_device_block); |
| 2404 | |
| 2405 | /** |
| 2406 | * scsi_internal_device_unblock - resume a device after a block request |
| 2407 | * @sdev: device to resume |
| 2408 | * |
| 2409 | * Called by scsi lld's or the midlayer to restart the device queue |
| 2410 | * for the previously suspended scsi device. Called from interrupt or |
| 2411 | * normal process context. |
| 2412 | * |
| 2413 | * Returns zero if successful or error if not. |
| 2414 | * |
| 2415 | * Notes: |
| 2416 | * This routine transitions the device to the SDEV_RUNNING state |
| 2417 | * (which must be a legal transition) allowing the midlayer to |
| 2418 | * goose the queue for this device. This routine assumes the |
| 2419 | * host_lock is held upon entry. |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 2420 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2421 | int |
| 2422 | scsi_internal_device_unblock(struct scsi_device *sdev) |
| 2423 | { |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 2424 | struct request_queue *q = sdev->request_queue; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2425 | unsigned long flags; |
| 2426 | |
| 2427 | /* |
| 2428 | * Try to transition the scsi device to SDEV_RUNNING |
| 2429 | * and goose the device queue if successful. |
| 2430 | */ |
Takahiro Yasui | 5c10e63 | 2009-04-29 12:13:02 -0400 | [diff] [blame] | 2431 | if (sdev->sdev_state == SDEV_BLOCK) |
| 2432 | sdev->sdev_state = SDEV_RUNNING; |
| 2433 | else if (sdev->sdev_state == SDEV_CREATED_BLOCK) |
| 2434 | sdev->sdev_state = SDEV_CREATED; |
Mike Christie | 986fe6c | 2010-10-06 03:10:59 -0500 | [diff] [blame] | 2435 | else if (sdev->sdev_state != SDEV_CANCEL && |
| 2436 | sdev->sdev_state != SDEV_OFFLINE) |
Takahiro Yasui | 5c10e63 | 2009-04-29 12:13:02 -0400 | [diff] [blame] | 2437 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2438 | |
| 2439 | spin_lock_irqsave(q->queue_lock, flags); |
| 2440 | blk_start_queue(q); |
| 2441 | spin_unlock_irqrestore(q->queue_lock, flags); |
| 2442 | |
| 2443 | return 0; |
| 2444 | } |
| 2445 | EXPORT_SYMBOL_GPL(scsi_internal_device_unblock); |
| 2446 | |
| 2447 | static void |
| 2448 | device_block(struct scsi_device *sdev, void *data) |
| 2449 | { |
| 2450 | scsi_internal_device_block(sdev); |
| 2451 | } |
| 2452 | |
| 2453 | static int |
| 2454 | target_block(struct device *dev, void *data) |
| 2455 | { |
| 2456 | if (scsi_is_target_device(dev)) |
| 2457 | starget_for_each_device(to_scsi_target(dev), NULL, |
| 2458 | device_block); |
| 2459 | return 0; |
| 2460 | } |
| 2461 | |
| 2462 | void |
| 2463 | scsi_target_block(struct device *dev) |
| 2464 | { |
| 2465 | if (scsi_is_target_device(dev)) |
| 2466 | starget_for_each_device(to_scsi_target(dev), NULL, |
| 2467 | device_block); |
| 2468 | else |
| 2469 | device_for_each_child(dev, NULL, target_block); |
| 2470 | } |
| 2471 | EXPORT_SYMBOL_GPL(scsi_target_block); |
| 2472 | |
| 2473 | static void |
| 2474 | device_unblock(struct scsi_device *sdev, void *data) |
| 2475 | { |
| 2476 | scsi_internal_device_unblock(sdev); |
| 2477 | } |
| 2478 | |
| 2479 | static int |
| 2480 | target_unblock(struct device *dev, void *data) |
| 2481 | { |
| 2482 | if (scsi_is_target_device(dev)) |
| 2483 | starget_for_each_device(to_scsi_target(dev), NULL, |
| 2484 | device_unblock); |
| 2485 | return 0; |
| 2486 | } |
| 2487 | |
| 2488 | void |
| 2489 | scsi_target_unblock(struct device *dev) |
| 2490 | { |
| 2491 | if (scsi_is_target_device(dev)) |
| 2492 | starget_for_each_device(to_scsi_target(dev), NULL, |
| 2493 | device_unblock); |
| 2494 | else |
| 2495 | device_for_each_child(dev, NULL, target_unblock); |
| 2496 | } |
| 2497 | EXPORT_SYMBOL_GPL(scsi_target_unblock); |
Guennadi Liakhovetski | cdb8c2a | 2006-04-02 21:57:43 +0200 | [diff] [blame] | 2498 | |
| 2499 | /** |
| 2500 | * scsi_kmap_atomic_sg - find and atomically map an sg-elemnt |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 2501 | * @sgl: scatter-gather list |
Guennadi Liakhovetski | cdb8c2a | 2006-04-02 21:57:43 +0200 | [diff] [blame] | 2502 | * @sg_count: number of segments in sg |
| 2503 | * @offset: offset in bytes into sg, on return offset into the mapped area |
| 2504 | * @len: bytes to map, on return number of bytes mapped |
| 2505 | * |
| 2506 | * Returns virtual address of the start of the mapped page |
| 2507 | */ |
Jens Axboe | c6132da | 2007-10-16 11:08:49 +0200 | [diff] [blame] | 2508 | void *scsi_kmap_atomic_sg(struct scatterlist *sgl, int sg_count, |
Guennadi Liakhovetski | cdb8c2a | 2006-04-02 21:57:43 +0200 | [diff] [blame] | 2509 | size_t *offset, size_t *len) |
| 2510 | { |
| 2511 | int i; |
| 2512 | size_t sg_len = 0, len_complete = 0; |
Jens Axboe | c6132da | 2007-10-16 11:08:49 +0200 | [diff] [blame] | 2513 | struct scatterlist *sg; |
Guennadi Liakhovetski | cdb8c2a | 2006-04-02 21:57:43 +0200 | [diff] [blame] | 2514 | struct page *page; |
| 2515 | |
Andrew Morton | 22cfefb | 2007-02-05 16:39:03 -0800 | [diff] [blame] | 2516 | WARN_ON(!irqs_disabled()); |
| 2517 | |
Jens Axboe | c6132da | 2007-10-16 11:08:49 +0200 | [diff] [blame] | 2518 | for_each_sg(sgl, sg, sg_count, i) { |
Guennadi Liakhovetski | cdb8c2a | 2006-04-02 21:57:43 +0200 | [diff] [blame] | 2519 | len_complete = sg_len; /* Complete sg-entries */ |
Jens Axboe | c6132da | 2007-10-16 11:08:49 +0200 | [diff] [blame] | 2520 | sg_len += sg->length; |
Guennadi Liakhovetski | cdb8c2a | 2006-04-02 21:57:43 +0200 | [diff] [blame] | 2521 | if (sg_len > *offset) |
| 2522 | break; |
| 2523 | } |
| 2524 | |
| 2525 | if (unlikely(i == sg_count)) { |
Andrew Morton | 169e1a2 | 2006-04-18 21:09:08 -0700 | [diff] [blame] | 2526 | printk(KERN_ERR "%s: Bytes in sg: %zu, requested offset %zu, " |
| 2527 | "elements %d\n", |
Harvey Harrison | cadbd4a | 2008-07-03 23:47:27 -0700 | [diff] [blame] | 2528 | __func__, sg_len, *offset, sg_count); |
Guennadi Liakhovetski | cdb8c2a | 2006-04-02 21:57:43 +0200 | [diff] [blame] | 2529 | WARN_ON(1); |
| 2530 | return NULL; |
| 2531 | } |
| 2532 | |
| 2533 | /* Offset starting from the beginning of first page in this sg-entry */ |
Jens Axboe | c6132da | 2007-10-16 11:08:49 +0200 | [diff] [blame] | 2534 | *offset = *offset - len_complete + sg->offset; |
Guennadi Liakhovetski | cdb8c2a | 2006-04-02 21:57:43 +0200 | [diff] [blame] | 2535 | |
| 2536 | /* Assumption: contiguous pages can be accessed as "page + i" */ |
Jens Axboe | 45711f1 | 2007-10-22 21:19:53 +0200 | [diff] [blame] | 2537 | page = nth_page(sg_page(sg), (*offset >> PAGE_SHIFT)); |
Guennadi Liakhovetski | cdb8c2a | 2006-04-02 21:57:43 +0200 | [diff] [blame] | 2538 | *offset &= ~PAGE_MASK; |
| 2539 | |
| 2540 | /* Bytes in this sg-entry from *offset to the end of the page */ |
| 2541 | sg_len = PAGE_SIZE - *offset; |
| 2542 | if (*len > sg_len) |
| 2543 | *len = sg_len; |
| 2544 | |
| 2545 | return kmap_atomic(page, KM_BIO_SRC_IRQ); |
| 2546 | } |
| 2547 | EXPORT_SYMBOL(scsi_kmap_atomic_sg); |
| 2548 | |
| 2549 | /** |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 2550 | * scsi_kunmap_atomic_sg - atomically unmap a virtual address, previously mapped with scsi_kmap_atomic_sg |
Guennadi Liakhovetski | cdb8c2a | 2006-04-02 21:57:43 +0200 | [diff] [blame] | 2551 | * @virt: virtual address to be unmapped |
| 2552 | */ |
| 2553 | void scsi_kunmap_atomic_sg(void *virt) |
| 2554 | { |
| 2555 | kunmap_atomic(virt, KM_BIO_SRC_IRQ); |
| 2556 | } |
| 2557 | EXPORT_SYMBOL(scsi_kunmap_atomic_sg); |