[SCSI] tgt: fix sesnse buffer problems
This patch simplify the way to notify LLDs of the command completion
and addresses the following sense buffer problems:
- can't handle both data and sense.
- forces user-space to use aligned sense buffer
tgt copies sense_data from userspace to cmnd->sense_buffer (if
necessary), maps user-space pages (if necessary) and then calls
host->transfer_response (host->transfer_data is removed).
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/drivers/scsi/scsi_tgt_lib.c b/drivers/scsi/scsi_tgt_lib.c
index 47c29a9..dc8781a6 100644
--- a/drivers/scsi/scsi_tgt_lib.c
+++ b/drivers/scsi/scsi_tgt_lib.c
@@ -47,9 +47,6 @@
struct list_head hash_list;
struct request *rq;
u64 tag;
-
- void *buffer;
- unsigned bufflen;
};
#define TGT_HASH_ORDER 4
@@ -330,10 +327,14 @@
dprintk("cmd %p %lu\n", cmd, rq_data_dir(cmd->request));
scsi_tgt_uspace_send_status(cmd, tcmd->tag);
+
+ if (cmd->request_buffer)
+ scsi_free_sgtable(cmd->request_buffer, cmd->sglist_len);
+
queue_work(scsi_tgtd, &tcmd->work);
}
-static int __scsi_tgt_transfer_response(struct scsi_cmnd *cmd)
+static int scsi_tgt_transfer_response(struct scsi_cmnd *cmd)
{
struct Scsi_Host *shost = scsi_tgt_cmd_to_host(cmd);
int err;
@@ -346,30 +347,12 @@
case SCSI_MLQUEUE_DEVICE_BUSY:
return -EAGAIN;
}
-
return 0;
}
-static void scsi_tgt_transfer_response(struct scsi_cmnd *cmd)
-{
- struct scsi_tgt_cmd *tcmd = cmd->request->end_io_data;
- int err;
-
- err = __scsi_tgt_transfer_response(cmd);
- if (!err)
- return;
-
- cmd->result = DID_BUS_BUSY << 16;
- err = scsi_tgt_uspace_send_status(cmd, tcmd->tag);
- if (err <= 0)
- /* the eh will have to pick this up */
- printk(KERN_ERR "Could not send cmd %p status\n", cmd);
-}
-
static int scsi_tgt_init_cmd(struct scsi_cmnd *cmd, gfp_t gfp_mask)
{
struct request *rq = cmd->request;
- struct scsi_tgt_cmd *tcmd = rq->end_io_data;
int count;
cmd->use_sg = rq->nr_phys_segments;
@@ -379,31 +362,28 @@
cmd->request_bufflen = rq->data_len;
- dprintk("cmd %p addr %p cnt %d %lu\n", cmd, tcmd->buffer, cmd->use_sg,
- rq_data_dir(rq));
+ dprintk("cmd %p cnt %d %lu\n", cmd, cmd->use_sg, rq_data_dir(rq));
count = blk_rq_map_sg(rq->q, rq, cmd->request_buffer);
if (likely(count <= cmd->use_sg)) {
cmd->use_sg = count;
return 0;
}
- eprintk("cmd %p addr %p cnt %d\n", cmd, tcmd->buffer, cmd->use_sg);
+ eprintk("cmd %p cnt %d\n", cmd, cmd->use_sg);
scsi_free_sgtable(cmd->request_buffer, cmd->sglist_len);
return -EINVAL;
}
/* TODO: test this crap and replace bio_map_user with new interface maybe */
static int scsi_map_user_pages(struct scsi_tgt_cmd *tcmd, struct scsi_cmnd *cmd,
- int rw)
+ unsigned long uaddr, unsigned int len, int rw)
{
struct request_queue *q = cmd->request->q;
struct request *rq = cmd->request;
- void *uaddr = tcmd->buffer;
- unsigned int len = tcmd->bufflen;
int err;
- dprintk("%lx %u\n", (unsigned long) uaddr, len);
- err = blk_rq_map_user(q, rq, uaddr, len);
+ dprintk("%lx %u\n", uaddr, len);
+ err = blk_rq_map_user(q, rq, (void *)uaddr, len);
if (err) {
/*
* TODO: need to fixup sg_tablesize, max_segment_size,
@@ -430,45 +410,6 @@
return err;
}
-static int scsi_tgt_transfer_data(struct scsi_cmnd *);
-
-static void scsi_tgt_data_transfer_done(struct scsi_cmnd *cmd)
-{
- struct scsi_tgt_cmd *tcmd = cmd->request->end_io_data;
- int err;
-
- /* should we free resources here on error ? */
- if (cmd->result) {
- err = scsi_tgt_uspace_send_status(cmd, tcmd->tag);
- if (err <= 0)
- /* the tgt uspace eh will have to pick this up */
- printk(KERN_ERR "Could not send cmd %p status\n", cmd);
- return;
- }
-
- dprintk("cmd %p request_bufflen %u bufflen %u\n",
- cmd, cmd->request_bufflen, tcmd->bufflen);
-
- scsi_free_sgtable(cmd->request_buffer, cmd->sglist_len);
- tcmd->buffer += cmd->request_bufflen;
- scsi_tgt_transfer_response(cmd);
-}
-
-static int scsi_tgt_transfer_data(struct scsi_cmnd *cmd)
-{
- int err;
- struct Scsi_Host *host = scsi_tgt_cmd_to_host(cmd);
-
- err = host->hostt->transfer_data(cmd, scsi_tgt_data_transfer_done);
- switch (err) {
- case SCSI_MLQUEUE_HOST_BUSY:
- case SCSI_MLQUEUE_DEVICE_BUSY:
- return -EAGAIN;
- default:
- return 0;
- }
-}
-
static int scsi_tgt_copy_sense(struct scsi_cmnd *cmd, unsigned long uaddr,
unsigned len)
{
@@ -518,8 +459,9 @@
return rq;
}
-int scsi_tgt_kspace_exec(int host_no, u64 tag, int result, u32 len,
- unsigned long uaddr, u8 rw)
+int scsi_tgt_kspace_exec(int host_no, int result, u64 tag,
+ unsigned long uaddr, u32 len, unsigned long sense_uaddr,
+ u32 sense_len, u8 rw)
{
struct Scsi_Host *shost;
struct scsi_cmnd *cmd;
@@ -564,36 +506,20 @@
* in the request_* values
*/
tcmd = cmd->request->end_io_data;
- tcmd->buffer = (void *)uaddr;
- tcmd->bufflen = len;
cmd->result = result;
- if (!tcmd->bufflen || cmd->request_buffer) {
- err = __scsi_tgt_transfer_response(cmd);
- goto done;
- }
+ if (cmd->result == SAM_STAT_CHECK_CONDITION)
+ scsi_tgt_copy_sense(cmd, sense_uaddr, sense_len);
- /*
- * TODO: Do we need to handle case where request does not
- * align with LLD.
- */
- err = scsi_map_user_pages(rq->end_io_data, cmd, rw);
- if (err) {
- eprintk("%p %d\n", cmd, err);
- err = -EAGAIN;
- goto done;
+ if (len) {
+ err = scsi_map_user_pages(rq->end_io_data, cmd, uaddr, len, rw);
+ if (err) {
+ eprintk("%p %d\n", cmd, err);
+ err = -EAGAIN;
+ goto done;
+ }
}
-
- /* userspace failure */
- if (cmd->result) {
- if (status_byte(cmd->result) == CHECK_CONDITION)
- scsi_tgt_copy_sense(cmd, uaddr, len);
- err = __scsi_tgt_transfer_response(cmd);
- goto done;
- }
- /* ask the target LLD to transfer the data to the buffer */
- err = scsi_tgt_transfer_data(cmd);
-
+ err = scsi_tgt_transfer_response(cmd);
done:
scsi_host_put(shost);
return err;