Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/fs/nfs/direct.c |
| 3 | * |
| 4 | * Copyright (C) 2003 by Chuck Lever <cel@netapp.com> |
| 5 | * |
| 6 | * High-performance uncached I/O for the Linux NFS client |
| 7 | * |
| 8 | * There are important applications whose performance or correctness |
| 9 | * depends on uncached access to file data. Database clusters |
Chuck Lever | 8846705 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 10 | * (multiple copies of the same instance running on separate hosts) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | * implement their own cache coherency protocol that subsumes file |
Chuck Lever | 8846705 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 12 | * system cache protocols. Applications that process datasets |
| 13 | * considerably larger than the client's memory do not always benefit |
| 14 | * from a local cache. A streaming video server, for instance, has no |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | * need to cache the contents of a file. |
| 16 | * |
| 17 | * When an application requests uncached I/O, all read and write requests |
| 18 | * are made directly to the server; data stored or fetched via these |
| 19 | * requests is not cached in the Linux page cache. The client does not |
| 20 | * correct unaligned requests from applications. All requested bytes are |
| 21 | * held on permanent storage before a direct write system call returns to |
| 22 | * an application. |
| 23 | * |
| 24 | * Solaris implements an uncached I/O facility called directio() that |
| 25 | * is used for backups and sequential I/O to very large files. Solaris |
| 26 | * also supports uncaching whole NFS partitions with "-o forcedirectio," |
| 27 | * an undocumented mount option. |
| 28 | * |
| 29 | * Designed by Jeff Kimmel, Chuck Lever, and Trond Myklebust, with |
| 30 | * help from Andrew Morton. |
| 31 | * |
| 32 | * 18 Dec 2001 Initial implementation for 2.4 --cel |
| 33 | * 08 Jul 2002 Version for 2.4.19, with bug fixes --trondmy |
| 34 | * 08 Jun 2003 Port to 2.5 APIs --cel |
| 35 | * 31 Mar 2004 Handle direct I/O without VFS support --cel |
| 36 | * 15 Sep 2004 Parallel async reads --cel |
Chuck Lever | 8846705 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 37 | * 04 May 2005 support O_DIRECT with aio --cel |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | * |
| 39 | */ |
| 40 | |
| 41 | #include <linux/config.h> |
| 42 | #include <linux/errno.h> |
| 43 | #include <linux/sched.h> |
| 44 | #include <linux/kernel.h> |
| 45 | #include <linux/smp_lock.h> |
| 46 | #include <linux/file.h> |
| 47 | #include <linux/pagemap.h> |
| 48 | #include <linux/kref.h> |
| 49 | |
| 50 | #include <linux/nfs_fs.h> |
| 51 | #include <linux/nfs_page.h> |
| 52 | #include <linux/sunrpc/clnt.h> |
| 53 | |
| 54 | #include <asm/system.h> |
| 55 | #include <asm/uaccess.h> |
| 56 | #include <asm/atomic.h> |
| 57 | |
Chuck Lever | 91d5b47 | 2006-03-20 13:44:14 -0500 | [diff] [blame] | 58 | #include "iostat.h" |
| 59 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 60 | #define NFSDBG_FACILITY NFSDBG_VFS |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 61 | |
| 62 | static kmem_cache_t *nfs_direct_cachep; |
| 63 | |
| 64 | /* |
| 65 | * This represents a set of asynchronous requests that we're waiting on |
| 66 | */ |
| 67 | struct nfs_direct_req { |
| 68 | struct kref kref; /* release manager */ |
Chuck Lever | 15ce4a0 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 69 | |
| 70 | /* I/O parameters */ |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 71 | struct list_head list, /* nfs_read/write_data structs */ |
| 72 | rewrite_list; /* saved nfs_write_data structs */ |
Trond Myklebust | a8881f5 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 73 | struct nfs_open_context *ctx; /* file open context info */ |
Chuck Lever | 99514f8 | 2006-03-20 13:44:30 -0500 | [diff] [blame] | 74 | struct kiocb * iocb; /* controlling i/o request */ |
Chuck Lever | 8846705 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 75 | struct inode * inode; /* target file of i/o */ |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 76 | unsigned long user_addr; /* location of user's buffer */ |
| 77 | size_t user_count; /* total bytes to move */ |
| 78 | loff_t pos; /* starting offset in file */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 79 | struct page ** pages; /* pages in our buffer */ |
| 80 | unsigned int npages; /* count of pages */ |
Chuck Lever | 15ce4a0 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 81 | |
| 82 | /* completion state */ |
| 83 | spinlock_t lock; /* protect completion state */ |
| 84 | int outstanding; /* i/os we're waiting for */ |
| 85 | ssize_t count, /* bytes actually processed */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 86 | error; /* any reported error */ |
Trond Myklebust | d72b7a6 | 2006-03-20 13:44:43 -0500 | [diff] [blame^] | 87 | struct completion completion; /* wait for i/o completion */ |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 88 | |
| 89 | /* commit state */ |
| 90 | struct nfs_write_data * commit_data; /* special write_data for commits */ |
| 91 | int flags; |
| 92 | #define NFS_ODIRECT_DO_COMMIT (1) /* an unstable reply was received */ |
| 93 | #define NFS_ODIRECT_RESCHED_WRITES (2) /* write verification failed */ |
| 94 | struct nfs_writeverf verf; /* unstable write verifier */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 95 | }; |
| 96 | |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 97 | static void nfs_direct_write_schedule(struct nfs_direct_req *dreq, int sync); |
| 98 | static void nfs_direct_write_complete(struct nfs_direct_req *dreq, struct inode *inode); |
| 99 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 100 | /** |
Chuck Lever | b8a32e2 | 2006-03-20 13:44:28 -0500 | [diff] [blame] | 101 | * nfs_direct_IO - NFS address space operation for direct I/O |
| 102 | * @rw: direction (read or write) |
| 103 | * @iocb: target I/O control block |
| 104 | * @iov: array of vectors that define I/O buffer |
| 105 | * @pos: offset in file to begin the operation |
| 106 | * @nr_segs: size of iovec array |
| 107 | * |
| 108 | * The presence of this routine in the address space ops vector means |
| 109 | * the NFS client supports direct I/O. However, we shunt off direct |
| 110 | * read and write requests before the VFS gets them, so this method |
| 111 | * should never be called. |
| 112 | */ |
| 113 | ssize_t nfs_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov, loff_t pos, unsigned long nr_segs) |
| 114 | { |
| 115 | struct dentry *dentry = iocb->ki_filp->f_dentry; |
| 116 | |
| 117 | dprintk("NFS: nfs_direct_IO (%s) off/no(%Ld/%lu) EINVAL\n", |
| 118 | dentry->d_name.name, (long long) pos, nr_segs); |
| 119 | |
| 120 | return -EINVAL; |
| 121 | } |
| 122 | |
Trond Myklebust | 6b45d85 | 2006-03-20 13:44:43 -0500 | [diff] [blame] | 123 | static void nfs_free_user_pages(struct page **pages, int npages, int do_dirty) |
| 124 | { |
| 125 | int i; |
| 126 | for (i = 0; i < npages; i++) { |
| 127 | struct page *page = pages[i]; |
| 128 | if (do_dirty && !PageCompound(page)) |
| 129 | set_page_dirty_lock(page); |
| 130 | page_cache_release(page); |
| 131 | } |
| 132 | kfree(pages); |
| 133 | } |
| 134 | |
Chuck Lever | d4cc948 | 2006-03-20 13:44:28 -0500 | [diff] [blame] | 135 | static inline int nfs_get_user_pages(int rw, unsigned long user_addr, size_t size, struct page ***pages) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 136 | { |
| 137 | int result = -ENOMEM; |
| 138 | unsigned long page_count; |
| 139 | size_t array_size; |
| 140 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 141 | page_count = (user_addr + size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
| 142 | page_count -= user_addr >> PAGE_SHIFT; |
| 143 | |
| 144 | array_size = (page_count * sizeof(struct page *)); |
| 145 | *pages = kmalloc(array_size, GFP_KERNEL); |
| 146 | if (*pages) { |
| 147 | down_read(¤t->mm->mmap_sem); |
| 148 | result = get_user_pages(current, current->mm, user_addr, |
| 149 | page_count, (rw == READ), 0, |
| 150 | *pages, NULL); |
| 151 | up_read(¤t->mm->mmap_sem); |
Trond Myklebust | 6b45d85 | 2006-03-20 13:44:43 -0500 | [diff] [blame] | 152 | if (result != page_count) { |
| 153 | /* |
| 154 | * If we got fewer pages than expected from |
| 155 | * get_user_pages(), the user buffer runs off the |
| 156 | * end of a mapping; return EFAULT. |
| 157 | */ |
| 158 | if (result >= 0) { |
| 159 | nfs_free_user_pages(*pages, result, 0); |
| 160 | result = -EFAULT; |
| 161 | } else |
| 162 | kfree(*pages); |
Trond Myklebust | 143f412 | 2006-03-13 21:20:46 -0800 | [diff] [blame] | 163 | *pages = NULL; |
Trond Myklebust | 143f412 | 2006-03-13 21:20:46 -0800 | [diff] [blame] | 164 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 165 | } |
| 166 | return result; |
| 167 | } |
| 168 | |
Chuck Lever | 93619e5 | 2006-03-20 13:44:31 -0500 | [diff] [blame] | 169 | static inline struct nfs_direct_req *nfs_direct_req_alloc(void) |
| 170 | { |
| 171 | struct nfs_direct_req *dreq; |
| 172 | |
| 173 | dreq = kmem_cache_alloc(nfs_direct_cachep, SLAB_KERNEL); |
| 174 | if (!dreq) |
| 175 | return NULL; |
| 176 | |
| 177 | kref_init(&dreq->kref); |
Trond Myklebust | d72b7a6 | 2006-03-20 13:44:43 -0500 | [diff] [blame^] | 178 | init_completion(&dreq->completion); |
Chuck Lever | 93619e5 | 2006-03-20 13:44:31 -0500 | [diff] [blame] | 179 | INIT_LIST_HEAD(&dreq->list); |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 180 | INIT_LIST_HEAD(&dreq->rewrite_list); |
Chuck Lever | 93619e5 | 2006-03-20 13:44:31 -0500 | [diff] [blame] | 181 | dreq->iocb = NULL; |
Trond Myklebust | a8881f5 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 182 | dreq->ctx = NULL; |
Chuck Lever | 15ce4a0 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 183 | spin_lock_init(&dreq->lock); |
| 184 | dreq->outstanding = 0; |
| 185 | dreq->count = 0; |
| 186 | dreq->error = 0; |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 187 | dreq->flags = 0; |
Chuck Lever | 93619e5 | 2006-03-20 13:44:31 -0500 | [diff] [blame] | 188 | |
| 189 | return dreq; |
| 190 | } |
| 191 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 192 | static void nfs_direct_req_release(struct kref *kref) |
| 193 | { |
| 194 | struct nfs_direct_req *dreq = container_of(kref, struct nfs_direct_req, kref); |
Trond Myklebust | a8881f5 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 195 | |
| 196 | if (dreq->ctx != NULL) |
| 197 | put_nfs_open_context(dreq->ctx); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 198 | kmem_cache_free(nfs_direct_cachep, dreq); |
| 199 | } |
| 200 | |
Chuck Lever | d4cc948 | 2006-03-20 13:44:28 -0500 | [diff] [blame] | 201 | /* |
Chuck Lever | bc0fb20 | 2006-03-20 13:44:31 -0500 | [diff] [blame] | 202 | * Collects and returns the final error value/byte-count. |
| 203 | */ |
| 204 | static ssize_t nfs_direct_wait(struct nfs_direct_req *dreq) |
| 205 | { |
Chuck Lever | 15ce4a0 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 206 | ssize_t result = -EIOCBQUEUED; |
Chuck Lever | bc0fb20 | 2006-03-20 13:44:31 -0500 | [diff] [blame] | 207 | |
| 208 | /* Async requests don't wait here */ |
| 209 | if (dreq->iocb) |
| 210 | goto out; |
| 211 | |
Trond Myklebust | d72b7a6 | 2006-03-20 13:44:43 -0500 | [diff] [blame^] | 212 | result = wait_for_completion_interruptible(&dreq->completion); |
Chuck Lever | bc0fb20 | 2006-03-20 13:44:31 -0500 | [diff] [blame] | 213 | |
| 214 | if (!result) |
Chuck Lever | 15ce4a0 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 215 | result = dreq->error; |
Chuck Lever | bc0fb20 | 2006-03-20 13:44:31 -0500 | [diff] [blame] | 216 | if (!result) |
Chuck Lever | 15ce4a0 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 217 | result = dreq->count; |
Chuck Lever | bc0fb20 | 2006-03-20 13:44:31 -0500 | [diff] [blame] | 218 | |
| 219 | out: |
| 220 | kref_put(&dreq->kref, nfs_direct_req_release); |
| 221 | return (ssize_t) result; |
| 222 | } |
| 223 | |
| 224 | /* |
Chuck Lever | 63ab46a | 2006-03-20 13:44:31 -0500 | [diff] [blame] | 225 | * We must hold a reference to all the pages in this direct read request |
| 226 | * until the RPCs complete. This could be long *after* we are woken up in |
| 227 | * nfs_direct_wait (for instance, if someone hits ^C on a slow server). |
| 228 | * |
| 229 | * In addition, synchronous I/O uses a stack-allocated iocb. Thus we |
| 230 | * can't trust the iocb is still valid here if this is a synchronous |
| 231 | * request. If the waiter is woken prematurely, the iocb is long gone. |
| 232 | */ |
| 233 | static void nfs_direct_complete(struct nfs_direct_req *dreq) |
| 234 | { |
| 235 | nfs_free_user_pages(dreq->pages, dreq->npages, 1); |
| 236 | |
| 237 | if (dreq->iocb) { |
Chuck Lever | 15ce4a0 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 238 | long res = (long) dreq->error; |
Chuck Lever | 63ab46a | 2006-03-20 13:44:31 -0500 | [diff] [blame] | 239 | if (!res) |
Chuck Lever | 15ce4a0 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 240 | res = (long) dreq->count; |
Chuck Lever | 63ab46a | 2006-03-20 13:44:31 -0500 | [diff] [blame] | 241 | aio_complete(dreq->iocb, res, 0); |
Trond Myklebust | d72b7a6 | 2006-03-20 13:44:43 -0500 | [diff] [blame^] | 242 | } |
| 243 | complete_all(&dreq->completion); |
Chuck Lever | 63ab46a | 2006-03-20 13:44:31 -0500 | [diff] [blame] | 244 | |
| 245 | kref_put(&dreq->kref, nfs_direct_req_release); |
| 246 | } |
| 247 | |
| 248 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 249 | * Note we also set the number of requests we have in the dreq when we are |
| 250 | * done. This prevents races with I/O completion so we will always wait |
| 251 | * until all requests have been dispatched and completed. |
| 252 | */ |
Chuck Lever | 5dd602f | 2006-03-20 13:44:29 -0500 | [diff] [blame] | 253 | static struct nfs_direct_req *nfs_direct_read_alloc(size_t nbytes, size_t rsize) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 254 | { |
| 255 | struct list_head *list; |
| 256 | struct nfs_direct_req *dreq; |
Chuck Lever | 40859d7 | 2005-11-30 18:09:02 -0500 | [diff] [blame] | 257 | unsigned int rpages = (rsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 258 | |
Chuck Lever | 93619e5 | 2006-03-20 13:44:31 -0500 | [diff] [blame] | 259 | dreq = nfs_direct_req_alloc(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 260 | if (!dreq) |
| 261 | return NULL; |
| 262 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 263 | list = &dreq->list; |
| 264 | for(;;) { |
Chuck Lever | 40859d7 | 2005-11-30 18:09:02 -0500 | [diff] [blame] | 265 | struct nfs_read_data *data = nfs_readdata_alloc(rpages); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 266 | |
| 267 | if (unlikely(!data)) { |
| 268 | while (!list_empty(list)) { |
| 269 | data = list_entry(list->next, |
| 270 | struct nfs_read_data, pages); |
| 271 | list_del(&data->pages); |
| 272 | nfs_readdata_free(data); |
| 273 | } |
| 274 | kref_put(&dreq->kref, nfs_direct_req_release); |
| 275 | return NULL; |
| 276 | } |
| 277 | |
| 278 | INIT_LIST_HEAD(&data->pages); |
| 279 | list_add(&data->pages, list); |
| 280 | |
| 281 | data->req = (struct nfs_page *) dreq; |
Chuck Lever | 15ce4a0 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 282 | dreq->outstanding++; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 283 | if (nbytes <= rsize) |
| 284 | break; |
| 285 | nbytes -= rsize; |
| 286 | } |
| 287 | kref_get(&dreq->kref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 288 | return dreq; |
| 289 | } |
| 290 | |
Trond Myklebust | ec06c09 | 2006-03-20 13:44:27 -0500 | [diff] [blame] | 291 | static void nfs_direct_read_result(struct rpc_task *task, void *calldata) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 292 | { |
Trond Myklebust | ec06c09 | 2006-03-20 13:44:27 -0500 | [diff] [blame] | 293 | struct nfs_read_data *data = calldata; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 294 | struct nfs_direct_req *dreq = (struct nfs_direct_req *) data->req; |
| 295 | |
Trond Myklebust | ec06c09 | 2006-03-20 13:44:27 -0500 | [diff] [blame] | 296 | if (nfs_readpage_result(task, data) != 0) |
| 297 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 298 | |
Chuck Lever | 15ce4a0 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 299 | spin_lock(&dreq->lock); |
| 300 | |
| 301 | if (likely(task->tk_status >= 0)) |
| 302 | dreq->count += data->res.count; |
| 303 | else |
| 304 | dreq->error = task->tk_status; |
| 305 | |
| 306 | if (--dreq->outstanding) { |
| 307 | spin_unlock(&dreq->lock); |
| 308 | return; |
| 309 | } |
| 310 | |
| 311 | spin_unlock(&dreq->lock); |
| 312 | nfs_direct_complete(dreq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 313 | } |
| 314 | |
Trond Myklebust | ec06c09 | 2006-03-20 13:44:27 -0500 | [diff] [blame] | 315 | static const struct rpc_call_ops nfs_read_direct_ops = { |
| 316 | .rpc_call_done = nfs_direct_read_result, |
| 317 | .rpc_release = nfs_readdata_release, |
| 318 | }; |
| 319 | |
Chuck Lever | d4cc948 | 2006-03-20 13:44:28 -0500 | [diff] [blame] | 320 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 321 | * For each nfs_read_data struct that was allocated on the list, dispatch |
| 322 | * an NFS READ operation |
| 323 | */ |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 324 | static void nfs_direct_read_schedule(struct nfs_direct_req *dreq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 325 | { |
Trond Myklebust | a8881f5 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 326 | struct nfs_open_context *ctx = dreq->ctx; |
| 327 | struct inode *inode = ctx->dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 328 | struct list_head *list = &dreq->list; |
| 329 | struct page **pages = dreq->pages; |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 330 | size_t count = dreq->user_count; |
| 331 | loff_t pos = dreq->pos; |
Chuck Lever | 5dd602f | 2006-03-20 13:44:29 -0500 | [diff] [blame] | 332 | size_t rsize = NFS_SERVER(inode)->rsize; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 333 | unsigned int curpage, pgbase; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 334 | |
| 335 | curpage = 0; |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 336 | pgbase = dreq->user_addr & ~PAGE_MASK; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 337 | do { |
| 338 | struct nfs_read_data *data; |
Chuck Lever | 5dd602f | 2006-03-20 13:44:29 -0500 | [diff] [blame] | 339 | size_t bytes; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 340 | |
| 341 | bytes = rsize; |
| 342 | if (count < rsize) |
| 343 | bytes = count; |
| 344 | |
Trond Myklebust | 5db3a7b | 2006-03-20 13:44:37 -0500 | [diff] [blame] | 345 | BUG_ON(list_empty(list)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 346 | data = list_entry(list->next, struct nfs_read_data, pages); |
| 347 | list_del_init(&data->pages); |
| 348 | |
| 349 | data->inode = inode; |
| 350 | data->cred = ctx->cred; |
| 351 | data->args.fh = NFS_FH(inode); |
| 352 | data->args.context = ctx; |
Chuck Lever | 8846705 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 353 | data->args.offset = pos; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 354 | data->args.pgbase = pgbase; |
| 355 | data->args.pages = &pages[curpage]; |
| 356 | data->args.count = bytes; |
| 357 | data->res.fattr = &data->fattr; |
| 358 | data->res.eof = 0; |
| 359 | data->res.count = bytes; |
| 360 | |
Trond Myklebust | ec06c09 | 2006-03-20 13:44:27 -0500 | [diff] [blame] | 361 | rpc_init_task(&data->task, NFS_CLIENT(inode), RPC_TASK_ASYNC, |
| 362 | &nfs_read_direct_ops, data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 363 | NFS_PROTO(inode)->read_setup(data); |
| 364 | |
| 365 | data->task.tk_cookie = (unsigned long) inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 366 | |
| 367 | lock_kernel(); |
| 368 | rpc_execute(&data->task); |
| 369 | unlock_kernel(); |
| 370 | |
Chuck Lever | 606bbba | 2006-03-20 13:44:42 -0500 | [diff] [blame] | 371 | dfprintk(VFS, "NFS: %5u initiated direct read call (req %s/%Ld, %zu bytes @ offset %Lu)\n", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 372 | data->task.tk_pid, |
| 373 | inode->i_sb->s_id, |
| 374 | (long long)NFS_FILEID(inode), |
| 375 | bytes, |
| 376 | (unsigned long long)data->args.offset); |
| 377 | |
Chuck Lever | 8846705 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 378 | pos += bytes; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 379 | pgbase += bytes; |
| 380 | curpage += pgbase >> PAGE_SHIFT; |
| 381 | pgbase &= ~PAGE_MASK; |
| 382 | |
| 383 | count -= bytes; |
| 384 | } while (count != 0); |
Trond Myklebust | 5db3a7b | 2006-03-20 13:44:37 -0500 | [diff] [blame] | 385 | BUG_ON(!list_empty(list)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 386 | } |
| 387 | |
Chuck Lever | 8846705 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 388 | static ssize_t nfs_direct_read(struct kiocb *iocb, unsigned long user_addr, size_t count, loff_t pos, struct page **pages, unsigned int nr_pages) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 389 | { |
| 390 | ssize_t result; |
| 391 | sigset_t oldset; |
Chuck Lever | 99514f8 | 2006-03-20 13:44:30 -0500 | [diff] [blame] | 392 | struct inode *inode = iocb->ki_filp->f_mapping->host; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 393 | struct rpc_clnt *clnt = NFS_CLIENT(inode); |
| 394 | struct nfs_direct_req *dreq; |
| 395 | |
| 396 | dreq = nfs_direct_read_alloc(count, NFS_SERVER(inode)->rsize); |
| 397 | if (!dreq) |
| 398 | return -ENOMEM; |
| 399 | |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 400 | dreq->user_addr = user_addr; |
| 401 | dreq->user_count = count; |
| 402 | dreq->pos = pos; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 403 | dreq->pages = pages; |
| 404 | dreq->npages = nr_pages; |
Chuck Lever | 91d5b47 | 2006-03-20 13:44:14 -0500 | [diff] [blame] | 405 | dreq->inode = inode; |
Trond Myklebust | a8881f5 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 406 | dreq->ctx = get_nfs_open_context((struct nfs_open_context *)iocb->ki_filp->private_data); |
Chuck Lever | 487b837 | 2006-03-20 13:44:30 -0500 | [diff] [blame] | 407 | if (!is_sync_kiocb(iocb)) |
| 408 | dreq->iocb = iocb; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 409 | |
Chuck Lever | 91d5b47 | 2006-03-20 13:44:14 -0500 | [diff] [blame] | 410 | nfs_add_stats(inode, NFSIOS_DIRECTREADBYTES, count); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 411 | rpc_clnt_sigmask(clnt, &oldset); |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 412 | nfs_direct_read_schedule(dreq); |
Chuck Lever | bc0fb20 | 2006-03-20 13:44:31 -0500 | [diff] [blame] | 413 | result = nfs_direct_wait(dreq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 414 | rpc_clnt_sigunmask(clnt, &oldset); |
| 415 | |
| 416 | return result; |
| 417 | } |
| 418 | |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 419 | static void nfs_direct_free_writedata(struct nfs_direct_req *dreq) |
| 420 | { |
| 421 | list_splice_init(&dreq->rewrite_list, &dreq->list); |
| 422 | while (!list_empty(&dreq->list)) { |
| 423 | struct nfs_write_data *data = list_entry(dreq->list.next, struct nfs_write_data, pages); |
| 424 | list_del(&data->pages); |
| 425 | nfs_writedata_release(data); |
| 426 | } |
| 427 | } |
| 428 | |
| 429 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) |
| 430 | static void nfs_direct_write_reschedule(struct nfs_direct_req *dreq) |
| 431 | { |
| 432 | struct list_head *pos; |
| 433 | |
| 434 | list_splice_init(&dreq->rewrite_list, &dreq->list); |
| 435 | list_for_each(pos, &dreq->list) |
| 436 | dreq->outstanding++; |
| 437 | dreq->count = 0; |
| 438 | |
| 439 | nfs_direct_write_schedule(dreq, FLUSH_STABLE); |
| 440 | } |
| 441 | |
| 442 | static void nfs_direct_commit_result(struct rpc_task *task, void *calldata) |
| 443 | { |
| 444 | struct nfs_write_data *data = calldata; |
| 445 | struct nfs_direct_req *dreq = (struct nfs_direct_req *) data->req; |
| 446 | |
| 447 | /* Call the NFS version-specific code */ |
| 448 | if (NFS_PROTO(data->inode)->commit_done(task, data) != 0) |
| 449 | return; |
| 450 | if (unlikely(task->tk_status < 0)) { |
| 451 | dreq->error = task->tk_status; |
| 452 | dreq->flags = NFS_ODIRECT_RESCHED_WRITES; |
| 453 | } |
| 454 | if (memcmp(&dreq->verf, &data->verf, sizeof(data->verf))) { |
| 455 | dprintk("NFS: %5u commit verify failed\n", task->tk_pid); |
| 456 | dreq->flags = NFS_ODIRECT_RESCHED_WRITES; |
| 457 | } |
| 458 | |
| 459 | dprintk("NFS: %5u commit returned %d\n", task->tk_pid, task->tk_status); |
| 460 | nfs_direct_write_complete(dreq, data->inode); |
| 461 | } |
| 462 | |
| 463 | static const struct rpc_call_ops nfs_commit_direct_ops = { |
| 464 | .rpc_call_done = nfs_direct_commit_result, |
| 465 | .rpc_release = nfs_commit_release, |
| 466 | }; |
| 467 | |
| 468 | static void nfs_direct_commit_schedule(struct nfs_direct_req *dreq) |
| 469 | { |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 470 | struct nfs_write_data *data = dreq->commit_data; |
| 471 | struct rpc_task *task = &data->task; |
| 472 | |
| 473 | data->inode = dreq->inode; |
Trond Myklebust | a8881f5 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 474 | data->cred = dreq->ctx->cred; |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 475 | |
| 476 | data->args.fh = NFS_FH(data->inode); |
| 477 | data->args.offset = dreq->pos; |
| 478 | data->args.count = dreq->user_count; |
| 479 | data->res.count = 0; |
| 480 | data->res.fattr = &data->fattr; |
| 481 | data->res.verf = &data->verf; |
| 482 | |
| 483 | rpc_init_task(&data->task, NFS_CLIENT(dreq->inode), RPC_TASK_ASYNC, |
| 484 | &nfs_commit_direct_ops, data); |
| 485 | NFS_PROTO(data->inode)->commit_setup(data, 0); |
| 486 | |
| 487 | data->task.tk_priority = RPC_PRIORITY_NORMAL; |
| 488 | data->task.tk_cookie = (unsigned long)data->inode; |
| 489 | /* Note: task.tk_ops->rpc_release will free dreq->commit_data */ |
| 490 | dreq->commit_data = NULL; |
| 491 | |
| 492 | dprintk("NFS: %5u initiated commit call\n", task->tk_pid); |
| 493 | |
| 494 | lock_kernel(); |
| 495 | rpc_execute(&data->task); |
| 496 | unlock_kernel(); |
| 497 | } |
| 498 | |
| 499 | static void nfs_direct_write_complete(struct nfs_direct_req *dreq, struct inode *inode) |
| 500 | { |
| 501 | int flags = dreq->flags; |
| 502 | |
| 503 | dreq->flags = 0; |
| 504 | switch (flags) { |
| 505 | case NFS_ODIRECT_DO_COMMIT: |
| 506 | nfs_direct_commit_schedule(dreq); |
| 507 | break; |
| 508 | case NFS_ODIRECT_RESCHED_WRITES: |
| 509 | nfs_direct_write_reschedule(dreq); |
| 510 | break; |
| 511 | default: |
| 512 | nfs_end_data_update(inode); |
| 513 | if (dreq->commit_data != NULL) |
| 514 | nfs_commit_free(dreq->commit_data); |
| 515 | nfs_direct_free_writedata(dreq); |
| 516 | nfs_direct_complete(dreq); |
| 517 | } |
| 518 | } |
| 519 | |
| 520 | static void nfs_alloc_commit_data(struct nfs_direct_req *dreq) |
| 521 | { |
| 522 | dreq->commit_data = nfs_commit_alloc(0); |
| 523 | if (dreq->commit_data != NULL) |
| 524 | dreq->commit_data->req = (struct nfs_page *) dreq; |
| 525 | } |
| 526 | #else |
| 527 | static inline void nfs_alloc_commit_data(struct nfs_direct_req *dreq) |
| 528 | { |
| 529 | dreq->commit_data = NULL; |
| 530 | } |
| 531 | |
| 532 | static void nfs_direct_write_complete(struct nfs_direct_req *dreq, struct inode *inode) |
| 533 | { |
| 534 | nfs_end_data_update(inode); |
| 535 | nfs_direct_free_writedata(dreq); |
| 536 | nfs_direct_complete(dreq); |
| 537 | } |
| 538 | #endif |
| 539 | |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 540 | static struct nfs_direct_req *nfs_direct_write_alloc(size_t nbytes, size_t wsize) |
| 541 | { |
| 542 | struct list_head *list; |
| 543 | struct nfs_direct_req *dreq; |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 544 | unsigned int wpages = (wsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; |
| 545 | |
| 546 | dreq = nfs_direct_req_alloc(); |
| 547 | if (!dreq) |
| 548 | return NULL; |
| 549 | |
| 550 | list = &dreq->list; |
| 551 | for(;;) { |
| 552 | struct nfs_write_data *data = nfs_writedata_alloc(wpages); |
| 553 | |
| 554 | if (unlikely(!data)) { |
| 555 | while (!list_empty(list)) { |
| 556 | data = list_entry(list->next, |
| 557 | struct nfs_write_data, pages); |
| 558 | list_del(&data->pages); |
| 559 | nfs_writedata_free(data); |
| 560 | } |
| 561 | kref_put(&dreq->kref, nfs_direct_req_release); |
| 562 | return NULL; |
| 563 | } |
| 564 | |
| 565 | INIT_LIST_HEAD(&data->pages); |
| 566 | list_add(&data->pages, list); |
| 567 | |
| 568 | data->req = (struct nfs_page *) dreq; |
Chuck Lever | 15ce4a0 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 569 | dreq->outstanding++; |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 570 | if (nbytes <= wsize) |
| 571 | break; |
| 572 | nbytes -= wsize; |
| 573 | } |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 574 | |
| 575 | nfs_alloc_commit_data(dreq); |
| 576 | |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 577 | kref_get(&dreq->kref); |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 578 | return dreq; |
| 579 | } |
| 580 | |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 581 | static void nfs_direct_write_result(struct rpc_task *task, void *calldata) |
| 582 | { |
| 583 | struct nfs_write_data *data = calldata; |
| 584 | struct nfs_direct_req *dreq = (struct nfs_direct_req *) data->req; |
| 585 | int status = task->tk_status; |
| 586 | |
| 587 | if (nfs_writeback_done(task, data) != 0) |
| 588 | return; |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 589 | |
Chuck Lever | 15ce4a0 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 590 | spin_lock(&dreq->lock); |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 591 | |
Chuck Lever | 15ce4a0 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 592 | if (likely(status >= 0)) |
| 593 | dreq->count += data->res.count; |
| 594 | else |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 595 | dreq->error = task->tk_status; |
Chuck Lever | 15ce4a0 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 596 | |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 597 | if (data->res.verf->committed != NFS_FILE_SYNC) { |
| 598 | switch (dreq->flags) { |
| 599 | case 0: |
| 600 | memcpy(&dreq->verf, &data->verf, sizeof(dreq->verf)); |
| 601 | dreq->flags = NFS_ODIRECT_DO_COMMIT; |
| 602 | break; |
| 603 | case NFS_ODIRECT_DO_COMMIT: |
| 604 | if (memcmp(&dreq->verf, &data->verf, sizeof(dreq->verf))) { |
| 605 | dprintk("NFS: %5u write verify failed\n", task->tk_pid); |
| 606 | dreq->flags = NFS_ODIRECT_RESCHED_WRITES; |
| 607 | } |
| 608 | } |
| 609 | } |
| 610 | /* In case we have to resend */ |
| 611 | data->args.stable = NFS_FILE_SYNC; |
| 612 | |
| 613 | spin_unlock(&dreq->lock); |
| 614 | } |
| 615 | |
| 616 | /* |
| 617 | * NB: Return the value of the first error return code. Subsequent |
| 618 | * errors after the first one are ignored. |
| 619 | */ |
| 620 | static void nfs_direct_write_release(void *calldata) |
| 621 | { |
| 622 | struct nfs_write_data *data = calldata; |
| 623 | struct nfs_direct_req *dreq = (struct nfs_direct_req *) data->req; |
| 624 | |
| 625 | spin_lock(&dreq->lock); |
Chuck Lever | 15ce4a0 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 626 | if (--dreq->outstanding) { |
| 627 | spin_unlock(&dreq->lock); |
| 628 | return; |
Chuck Lever | 9eafa8c | 2006-03-20 13:44:33 -0500 | [diff] [blame] | 629 | } |
Chuck Lever | 15ce4a0 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 630 | spin_unlock(&dreq->lock); |
| 631 | |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 632 | nfs_direct_write_complete(dreq, data->inode); |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 633 | } |
| 634 | |
| 635 | static const struct rpc_call_ops nfs_write_direct_ops = { |
| 636 | .rpc_call_done = nfs_direct_write_result, |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 637 | .rpc_release = nfs_direct_write_release, |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 638 | }; |
| 639 | |
| 640 | /* |
| 641 | * For each nfs_write_data struct that was allocated on the list, dispatch |
| 642 | * an NFS WRITE operation |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 643 | */ |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 644 | static void nfs_direct_write_schedule(struct nfs_direct_req *dreq, int sync) |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 645 | { |
Trond Myklebust | a8881f5 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 646 | struct nfs_open_context *ctx = dreq->ctx; |
| 647 | struct inode *inode = ctx->dentry->d_inode; |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 648 | struct list_head *list = &dreq->list; |
| 649 | struct page **pages = dreq->pages; |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 650 | size_t count = dreq->user_count; |
| 651 | loff_t pos = dreq->pos; |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 652 | size_t wsize = NFS_SERVER(inode)->wsize; |
| 653 | unsigned int curpage, pgbase; |
| 654 | |
| 655 | curpage = 0; |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 656 | pgbase = dreq->user_addr & ~PAGE_MASK; |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 657 | do { |
| 658 | struct nfs_write_data *data; |
| 659 | size_t bytes; |
| 660 | |
| 661 | bytes = wsize; |
| 662 | if (count < wsize) |
| 663 | bytes = count; |
| 664 | |
Trond Myklebust | 5db3a7b | 2006-03-20 13:44:37 -0500 | [diff] [blame] | 665 | BUG_ON(list_empty(list)); |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 666 | data = list_entry(list->next, struct nfs_write_data, pages); |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 667 | list_move_tail(&data->pages, &dreq->rewrite_list); |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 668 | |
| 669 | data->inode = inode; |
| 670 | data->cred = ctx->cred; |
| 671 | data->args.fh = NFS_FH(inode); |
| 672 | data->args.context = ctx; |
Chuck Lever | 8846705 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 673 | data->args.offset = pos; |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 674 | data->args.pgbase = pgbase; |
| 675 | data->args.pages = &pages[curpage]; |
| 676 | data->args.count = bytes; |
| 677 | data->res.fattr = &data->fattr; |
| 678 | data->res.count = bytes; |
Chuck Lever | 47989d7 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 679 | data->res.verf = &data->verf; |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 680 | |
| 681 | rpc_init_task(&data->task, NFS_CLIENT(inode), RPC_TASK_ASYNC, |
| 682 | &nfs_write_direct_ops, data); |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 683 | NFS_PROTO(inode)->write_setup(data, sync); |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 684 | |
| 685 | data->task.tk_priority = RPC_PRIORITY_NORMAL; |
| 686 | data->task.tk_cookie = (unsigned long) inode; |
| 687 | |
| 688 | lock_kernel(); |
| 689 | rpc_execute(&data->task); |
| 690 | unlock_kernel(); |
| 691 | |
Chuck Lever | 606bbba | 2006-03-20 13:44:42 -0500 | [diff] [blame] | 692 | dfprintk(VFS, "NFS: %5u initiated direct write call (req %s/%Ld, %zu bytes @ offset %Lu)\n", |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 693 | data->task.tk_pid, |
| 694 | inode->i_sb->s_id, |
| 695 | (long long)NFS_FILEID(inode), |
| 696 | bytes, |
| 697 | (unsigned long long)data->args.offset); |
| 698 | |
Chuck Lever | 8846705 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 699 | pos += bytes; |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 700 | pgbase += bytes; |
| 701 | curpage += pgbase >> PAGE_SHIFT; |
| 702 | pgbase &= ~PAGE_MASK; |
| 703 | |
| 704 | count -= bytes; |
| 705 | } while (count != 0); |
Trond Myklebust | 5db3a7b | 2006-03-20 13:44:37 -0500 | [diff] [blame] | 706 | BUG_ON(!list_empty(list)); |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 707 | } |
| 708 | |
Chuck Lever | 8846705 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 709 | static ssize_t nfs_direct_write(struct kiocb *iocb, unsigned long user_addr, size_t count, loff_t pos, struct page **pages, int nr_pages) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 710 | { |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 711 | ssize_t result; |
| 712 | sigset_t oldset; |
Chuck Lever | c89f2ee | 2006-03-20 13:44:33 -0500 | [diff] [blame] | 713 | struct inode *inode = iocb->ki_filp->f_mapping->host; |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 714 | struct rpc_clnt *clnt = NFS_CLIENT(inode); |
| 715 | struct nfs_direct_req *dreq; |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 716 | size_t wsize = NFS_SERVER(inode)->wsize; |
| 717 | int sync = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 718 | |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 719 | dreq = nfs_direct_write_alloc(count, wsize); |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 720 | if (!dreq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 721 | return -ENOMEM; |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 722 | if (dreq->commit_data == NULL || count < wsize) |
| 723 | sync = FLUSH_STABLE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 724 | |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 725 | dreq->user_addr = user_addr; |
| 726 | dreq->user_count = count; |
| 727 | dreq->pos = pos; |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 728 | dreq->pages = pages; |
| 729 | dreq->npages = nr_pages; |
Chuck Lever | c89f2ee | 2006-03-20 13:44:33 -0500 | [diff] [blame] | 730 | dreq->inode = inode; |
Trond Myklebust | a8881f5 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 731 | dreq->ctx = get_nfs_open_context((struct nfs_open_context *)iocb->ki_filp->private_data); |
Chuck Lever | c89f2ee | 2006-03-20 13:44:33 -0500 | [diff] [blame] | 732 | if (!is_sync_kiocb(iocb)) |
| 733 | dreq->iocb = iocb; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 734 | |
Chuck Lever | 47989d7 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 735 | nfs_add_stats(inode, NFSIOS_DIRECTWRITTENBYTES, count); |
| 736 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 737 | nfs_begin_data_update(inode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 738 | |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 739 | rpc_clnt_sigmask(clnt, &oldset); |
Trond Myklebust | fad6149 | 2006-03-20 13:44:36 -0500 | [diff] [blame] | 740 | nfs_direct_write_schedule(dreq, sync); |
Chuck Lever | c89f2ee | 2006-03-20 13:44:33 -0500 | [diff] [blame] | 741 | result = nfs_direct_wait(dreq); |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 742 | rpc_clnt_sigunmask(clnt, &oldset); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 743 | |
Chuck Lever | 462d5b3 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 744 | return result; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 745 | } |
| 746 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 747 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 748 | * nfs_file_direct_read - file direct read operation for NFS files |
| 749 | * @iocb: target I/O control block |
| 750 | * @buf: user's buffer into which to read data |
Chuck Lever | 8846705 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 751 | * @count: number of bytes to read |
| 752 | * @pos: byte offset in file where reading starts |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 753 | * |
| 754 | * We use this function for direct reads instead of calling |
| 755 | * generic_file_aio_read() in order to avoid gfar's check to see if |
| 756 | * the request starts before the end of the file. For that check |
| 757 | * to work, we must generate a GETATTR before each direct read, and |
| 758 | * even then there is a window between the GETATTR and the subsequent |
Chuck Lever | 8846705 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 759 | * READ where the file size could change. Our preference is simply |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 760 | * to do all reads the application wants, and the server will take |
| 761 | * care of managing the end of file boundary. |
Chuck Lever | 8846705 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 762 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 763 | * This function also eliminates unnecessarily updating the file's |
| 764 | * atime locally, as the NFS server sets the file's atime, and this |
| 765 | * client must read the updated atime from the server back into its |
| 766 | * cache. |
| 767 | */ |
Chuck Lever | d4cc948 | 2006-03-20 13:44:28 -0500 | [diff] [blame] | 768 | ssize_t nfs_file_direct_read(struct kiocb *iocb, char __user *buf, size_t count, loff_t pos) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 769 | { |
| 770 | ssize_t retval = -EINVAL; |
Chuck Lever | 0cdd80d | 2006-03-20 13:44:29 -0500 | [diff] [blame] | 771 | int page_count; |
| 772 | struct page **pages; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 773 | struct file *file = iocb->ki_filp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 774 | struct address_space *mapping = file->f_mapping; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 775 | |
Chuck Lever | ce1a8e6 | 2005-11-30 18:08:17 -0500 | [diff] [blame] | 776 | dprintk("nfs: direct read(%s/%s, %lu@%Ld)\n", |
Chuck Lever | 0bbacc4 | 2005-11-01 16:53:32 -0500 | [diff] [blame] | 777 | file->f_dentry->d_parent->d_name.name, |
| 778 | file->f_dentry->d_name.name, |
Chuck Lever | ce1a8e6 | 2005-11-30 18:08:17 -0500 | [diff] [blame] | 779 | (unsigned long) count, (long long) pos); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 780 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 781 | if (count < 0) |
| 782 | goto out; |
| 783 | retval = -EFAULT; |
Chuck Lever | 0cdd80d | 2006-03-20 13:44:29 -0500 | [diff] [blame] | 784 | if (!access_ok(VERIFY_WRITE, buf, count)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 785 | goto out; |
| 786 | retval = 0; |
| 787 | if (!count) |
| 788 | goto out; |
| 789 | |
Trond Myklebust | 29884df | 2005-12-13 16:13:54 -0500 | [diff] [blame] | 790 | retval = nfs_sync_mapping(mapping); |
| 791 | if (retval) |
| 792 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 793 | |
Trond Myklebust | 6b45d85 | 2006-03-20 13:44:43 -0500 | [diff] [blame] | 794 | retval = nfs_get_user_pages(READ, (unsigned long) buf, |
Chuck Lever | 0cdd80d | 2006-03-20 13:44:29 -0500 | [diff] [blame] | 795 | count, &pages); |
Trond Myklebust | 6b45d85 | 2006-03-20 13:44:43 -0500 | [diff] [blame] | 796 | if (retval < 0) |
Chuck Lever | 0cdd80d | 2006-03-20 13:44:29 -0500 | [diff] [blame] | 797 | goto out; |
Trond Myklebust | 6b45d85 | 2006-03-20 13:44:43 -0500 | [diff] [blame] | 798 | page_count = retval; |
Chuck Lever | 0cdd80d | 2006-03-20 13:44:29 -0500 | [diff] [blame] | 799 | |
Chuck Lever | 99514f8 | 2006-03-20 13:44:30 -0500 | [diff] [blame] | 800 | retval = nfs_direct_read(iocb, (unsigned long) buf, count, pos, |
Chuck Lever | 0cdd80d | 2006-03-20 13:44:29 -0500 | [diff] [blame] | 801 | pages, page_count); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 802 | if (retval > 0) |
Chuck Lever | 0cdd80d | 2006-03-20 13:44:29 -0500 | [diff] [blame] | 803 | iocb->ki_pos = pos + retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 804 | |
| 805 | out: |
| 806 | return retval; |
| 807 | } |
| 808 | |
| 809 | /** |
| 810 | * nfs_file_direct_write - file direct write operation for NFS files |
| 811 | * @iocb: target I/O control block |
| 812 | * @buf: user's buffer from which to write data |
Chuck Lever | 8846705 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 813 | * @count: number of bytes to write |
| 814 | * @pos: byte offset in file where writing starts |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 815 | * |
| 816 | * We use this function for direct writes instead of calling |
| 817 | * generic_file_aio_write() in order to avoid taking the inode |
| 818 | * semaphore and updating the i_size. The NFS server will set |
| 819 | * the new i_size and this client must read the updated size |
| 820 | * back into its cache. We let the server do generic write |
| 821 | * parameter checking and report problems. |
| 822 | * |
| 823 | * We also avoid an unnecessary invocation of generic_osync_inode(), |
| 824 | * as it is fairly meaningless to sync the metadata of an NFS file. |
| 825 | * |
| 826 | * We eliminate local atime updates, see direct read above. |
| 827 | * |
| 828 | * We avoid unnecessary page cache invalidations for normal cached |
| 829 | * readers of this file. |
| 830 | * |
| 831 | * Note that O_APPEND is not supported for NFS direct writes, as there |
| 832 | * is no atomic O_APPEND write facility in the NFS protocol. |
| 833 | */ |
Chuck Lever | d4cc948 | 2006-03-20 13:44:28 -0500 | [diff] [blame] | 834 | ssize_t nfs_file_direct_write(struct kiocb *iocb, const char __user *buf, size_t count, loff_t pos) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 835 | { |
Chuck Lever | ce1a8e6 | 2005-11-30 18:08:17 -0500 | [diff] [blame] | 836 | ssize_t retval; |
Chuck Lever | 47989d7 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 837 | int page_count; |
| 838 | struct page **pages; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 839 | struct file *file = iocb->ki_filp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 840 | struct address_space *mapping = file->f_mapping; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 841 | |
Chuck Lever | ce1a8e6 | 2005-11-30 18:08:17 -0500 | [diff] [blame] | 842 | dfprintk(VFS, "nfs: direct write(%s/%s, %lu@%Ld)\n", |
Chuck Lever | 0bbacc4 | 2005-11-01 16:53:32 -0500 | [diff] [blame] | 843 | file->f_dentry->d_parent->d_name.name, |
Chuck Lever | ce1a8e6 | 2005-11-30 18:08:17 -0500 | [diff] [blame] | 844 | file->f_dentry->d_name.name, |
| 845 | (unsigned long) count, (long long) pos); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 846 | |
Chuck Lever | ce1a8e6 | 2005-11-30 18:08:17 -0500 | [diff] [blame] | 847 | retval = generic_write_checks(file, &pos, &count, 0); |
| 848 | if (retval) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 849 | goto out; |
Chuck Lever | ce1a8e6 | 2005-11-30 18:08:17 -0500 | [diff] [blame] | 850 | |
| 851 | retval = -EINVAL; |
| 852 | if ((ssize_t) count < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 853 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 854 | retval = 0; |
| 855 | if (!count) |
| 856 | goto out; |
Chuck Lever | ce1a8e6 | 2005-11-30 18:08:17 -0500 | [diff] [blame] | 857 | |
| 858 | retval = -EFAULT; |
Chuck Lever | 47989d7 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 859 | if (!access_ok(VERIFY_READ, buf, count)) |
Chuck Lever | ce1a8e6 | 2005-11-30 18:08:17 -0500 | [diff] [blame] | 860 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 861 | |
Trond Myklebust | 29884df | 2005-12-13 16:13:54 -0500 | [diff] [blame] | 862 | retval = nfs_sync_mapping(mapping); |
| 863 | if (retval) |
| 864 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 865 | |
Trond Myklebust | 6b45d85 | 2006-03-20 13:44:43 -0500 | [diff] [blame] | 866 | retval = nfs_get_user_pages(WRITE, (unsigned long) buf, |
Chuck Lever | 47989d7 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 867 | count, &pages); |
Trond Myklebust | 6b45d85 | 2006-03-20 13:44:43 -0500 | [diff] [blame] | 868 | if (retval < 0) |
Chuck Lever | 47989d7 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 869 | goto out; |
Trond Myklebust | 6b45d85 | 2006-03-20 13:44:43 -0500 | [diff] [blame] | 870 | page_count = retval; |
Chuck Lever | 47989d7 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 871 | |
Chuck Lever | c89f2ee | 2006-03-20 13:44:33 -0500 | [diff] [blame] | 872 | retval = nfs_direct_write(iocb, (unsigned long) buf, count, |
Chuck Lever | 47989d7 | 2006-03-20 13:44:32 -0500 | [diff] [blame] | 873 | pos, pages, page_count); |
Chuck Lever | 9eafa8c | 2006-03-20 13:44:33 -0500 | [diff] [blame] | 874 | |
| 875 | /* |
| 876 | * XXX: nfs_end_data_update() already ensures this file's |
| 877 | * cached data is subsequently invalidated. Do we really |
| 878 | * need to call invalidate_inode_pages2() again here? |
| 879 | * |
| 880 | * For aio writes, this invalidation will almost certainly |
| 881 | * occur before the writes complete. Kind of racey. |
| 882 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 883 | if (mapping->nrpages) |
| 884 | invalidate_inode_pages2(mapping); |
Chuck Lever | 9eafa8c | 2006-03-20 13:44:33 -0500 | [diff] [blame] | 885 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 886 | if (retval > 0) |
Chuck Lever | ce1a8e6 | 2005-11-30 18:08:17 -0500 | [diff] [blame] | 887 | iocb->ki_pos = pos + retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 888 | |
| 889 | out: |
| 890 | return retval; |
| 891 | } |
| 892 | |
Chuck Lever | 8846705 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 893 | /** |
| 894 | * nfs_init_directcache - create a slab cache for nfs_direct_req structures |
| 895 | * |
| 896 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 897 | int nfs_init_directcache(void) |
| 898 | { |
| 899 | nfs_direct_cachep = kmem_cache_create("nfs_direct_cache", |
| 900 | sizeof(struct nfs_direct_req), |
| 901 | 0, SLAB_RECLAIM_ACCOUNT, |
| 902 | NULL, NULL); |
| 903 | if (nfs_direct_cachep == NULL) |
| 904 | return -ENOMEM; |
| 905 | |
| 906 | return 0; |
| 907 | } |
| 908 | |
Chuck Lever | 8846705 | 2006-03-20 13:44:34 -0500 | [diff] [blame] | 909 | /** |
| 910 | * nfs_init_directcache - destroy the slab cache for nfs_direct_req structures |
| 911 | * |
| 912 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 913 | void nfs_destroy_directcache(void) |
| 914 | { |
| 915 | if (kmem_cache_destroy(nfs_direct_cachep)) |
| 916 | printk(KERN_INFO "nfs_direct_cache: not all structures were freed\n"); |
| 917 | } |