4 * Copyright (C) 1992 Rick Sladkey
6 * Changes Copyright (C) 1994 by Florian La Roche
7 * - Do not copy data too often around in the kernel.
8 * - In nfs_file_read the return value of kmalloc wasn't checked.
9 * - Put in a better version of read look-ahead buffering. Original idea
10 * and implementation by Wai S Kok elekokws@ee.nus.sg.
12 * Expire cache on write to a file by Wai S Kok (Oct 1994).
14 * Total rewrite of read side for new NFS buffer cache.. Linus.
16 * nfs regular file handling functions
19 #include <linux/time.h>
20 #include <linux/kernel.h>
21 #include <linux/errno.h>
22 #include <linux/fcntl.h>
23 #include <linux/stat.h>
24 #include <linux/nfs_fs.h>
25 #include <linux/nfs_mount.h>
27 #include <linux/slab.h>
28 #include <linux/pagemap.h>
29 #include <linux/smp_lock.h>
31 #include <asm/uaccess.h>
32 #include <asm/system.h>
34 #include "delegation.h"
37 #define NFSDBG_FACILITY NFSDBG_FILE
39 static int nfs_file_open(struct inode *, struct file *);
40 static int nfs_file_release(struct inode *, struct file *);
41 static loff_t nfs_file_llseek(struct file *file, loff_t offset, int origin);
42 static int nfs_file_mmap(struct file *, struct vm_area_struct *);
43 static ssize_t nfs_file_sendfile(struct file *, loff_t *, size_t, read_actor_t, void *);
44 static ssize_t nfs_file_read(struct kiocb *, char __user *, size_t, loff_t);
45 static ssize_t nfs_file_write(struct kiocb *, const char __user *, size_t, loff_t);
46 static int nfs_file_flush(struct file *, fl_owner_t id);
47 static int nfs_fsync(struct file *, struct dentry *dentry, int datasync);
48 static int nfs_check_flags(int flags);
49 static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl);
50 static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl);
52 const struct file_operations nfs_file_operations = {
53 .llseek = nfs_file_llseek,
55 .write = do_sync_write,
56 .aio_read = nfs_file_read,
57 .aio_write = nfs_file_write,
58 .mmap = nfs_file_mmap,
59 .open = nfs_file_open,
60 .flush = nfs_file_flush,
61 .release = nfs_file_release,
65 .sendfile = nfs_file_sendfile,
66 .check_flags = nfs_check_flags,
69 struct inode_operations nfs_file_inode_operations = {
70 .permission = nfs_permission,
71 .getattr = nfs_getattr,
72 .setattr = nfs_setattr,
76 struct inode_operations nfs3_file_inode_operations = {
77 .permission = nfs_permission,
78 .getattr = nfs_getattr,
79 .setattr = nfs_setattr,
80 .listxattr = nfs3_listxattr,
81 .getxattr = nfs3_getxattr,
82 .setxattr = nfs3_setxattr,
83 .removexattr = nfs3_removexattr,
85 #endif /* CONFIG_NFS_v3 */
87 /* Hack for future NFS swap support */
89 # define IS_SWAPFILE(inode) (0)
92 static int nfs_check_flags(int flags)
94 if ((flags & (O_APPEND | O_DIRECT)) == (O_APPEND | O_DIRECT))
104 nfs_file_open(struct inode *inode, struct file *filp)
108 res = nfs_check_flags(filp->f_flags);
112 nfs_inc_stats(inode, NFSIOS_VFSOPEN);
114 res = NFS_SERVER(inode)->rpc_ops->file_open(inode, filp);
120 nfs_file_release(struct inode *inode, struct file *filp)
122 /* Ensure that dirty pages are flushed out with the right creds */
123 if (filp->f_mode & FMODE_WRITE)
124 filemap_fdatawrite(filp->f_mapping);
125 nfs_inc_stats(inode, NFSIOS_VFSRELEASE);
126 return NFS_PROTO(inode)->file_release(inode, filp);
130 * nfs_revalidate_size - Revalidate the file size
131 * @inode - pointer to inode struct
132 * @file - pointer to struct file
134 * Revalidates the file length. This is basically a wrapper around
135 * nfs_revalidate_inode() that takes into account the fact that we may
136 * have cached writes (in which case we don't care about the server's
137 * idea of what the file length is), or O_DIRECT (in which case we
138 * shouldn't trust the cache).
140 static int nfs_revalidate_file_size(struct inode *inode, struct file *filp)
142 struct nfs_server *server = NFS_SERVER(inode);
143 struct nfs_inode *nfsi = NFS_I(inode);
145 if (server->flags & NFS_MOUNT_NOAC)
147 if (filp->f_flags & O_DIRECT)
149 if (nfsi->npages != 0)
151 if (!(nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE) && !nfs_attribute_timeout(inode))
154 return __nfs_revalidate_inode(server, inode);
157 static loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin)
159 /* origin == SEEK_END => we must revalidate the cached file length */
161 struct inode *inode = filp->f_mapping->host;
162 int retval = nfs_revalidate_file_size(inode, filp);
164 return (loff_t)retval;
166 return remote_llseek(filp, offset, origin);
170 * Flush all dirty pages, and check for write errors.
174 nfs_file_flush(struct file *file, fl_owner_t id)
176 struct nfs_open_context *ctx = (struct nfs_open_context *)file->private_data;
177 struct inode *inode = file->f_dentry->d_inode;
180 dfprintk(VFS, "nfs: flush(%s/%ld)\n", inode->i_sb->s_id, inode->i_ino);
182 if ((file->f_mode & FMODE_WRITE) == 0)
184 nfs_inc_stats(inode, NFSIOS_VFSFLUSH);
186 /* Ensure that data+attribute caches are up to date after close() */
187 status = nfs_wb_all(inode);
192 nfs_revalidate_inode(NFS_SERVER(inode), inode);
199 nfs_file_read(struct kiocb *iocb, char __user * buf, size_t count, loff_t pos)
201 struct dentry * dentry = iocb->ki_filp->f_dentry;
202 struct inode * inode = dentry->d_inode;
205 #ifdef CONFIG_NFS_DIRECTIO
206 if (iocb->ki_filp->f_flags & O_DIRECT)
207 return nfs_file_direct_read(iocb, buf, count, pos);
210 dfprintk(VFS, "nfs: read(%s/%s, %lu@%lu)\n",
211 dentry->d_parent->d_name.name, dentry->d_name.name,
212 (unsigned long) count, (unsigned long) pos);
214 result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping);
215 nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, count);
217 result = generic_file_aio_read(iocb, buf, count, pos);
222 nfs_file_sendfile(struct file *filp, loff_t *ppos, size_t count,
223 read_actor_t actor, void *target)
225 struct dentry *dentry = filp->f_dentry;
226 struct inode *inode = dentry->d_inode;
229 dfprintk(VFS, "nfs: sendfile(%s/%s, %lu@%Lu)\n",
230 dentry->d_parent->d_name.name, dentry->d_name.name,
231 (unsigned long) count, (unsigned long long) *ppos);
233 res = nfs_revalidate_mapping(inode, filp->f_mapping);
235 res = generic_file_sendfile(filp, ppos, count, actor, target);
240 nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
242 struct dentry *dentry = file->f_dentry;
243 struct inode *inode = dentry->d_inode;
246 dfprintk(VFS, "nfs: mmap(%s/%s)\n",
247 dentry->d_parent->d_name.name, dentry->d_name.name);
249 status = nfs_revalidate_mapping(inode, file->f_mapping);
251 status = generic_file_mmap(file, vma);
256 * Flush any dirty pages for this process, and check for write errors.
257 * The return status from this call provides a reliable indication of
258 * whether any write errors occurred for this process.
261 nfs_fsync(struct file *file, struct dentry *dentry, int datasync)
263 struct nfs_open_context *ctx = (struct nfs_open_context *)file->private_data;
264 struct inode *inode = dentry->d_inode;
267 dfprintk(VFS, "nfs: fsync(%s/%ld)\n", inode->i_sb->s_id, inode->i_ino);
269 nfs_inc_stats(inode, NFSIOS_VFSFSYNC);
271 status = nfs_wb_all(inode);
281 * This does the "real" work of the write. The generic routine has
282 * allocated the page, locked it, done all the page alignment stuff
283 * calculations etc. Now we should just copy the data from user
284 * space and write it back to the real medium..
286 * If the writer ends up delaying the write, the writer needs to
287 * increment the page use counts until he is done with the page.
289 static int nfs_prepare_write(struct file *file, struct page *page, unsigned offset, unsigned to)
291 return nfs_flush_incompatible(file, page);
294 static int nfs_commit_write(struct file *file, struct page *page, unsigned offset, unsigned to)
299 status = nfs_updatepage(file, page, offset, to-offset);
304 static void nfs_invalidate_page(struct page *page, unsigned long offset)
306 struct inode *inode = page->mapping->host;
308 /* Cancel any unstarted writes on this page */
310 nfs_sync_inode_wait(inode, page->index, 1, FLUSH_INVALIDATE);
313 static int nfs_release_page(struct page *page, gfp_t gfp)
315 return !nfs_wb_page(page->mapping->host, page);
318 struct address_space_operations nfs_file_aops = {
319 .readpage = nfs_readpage,
320 .readpages = nfs_readpages,
321 .set_page_dirty = __set_page_dirty_nobuffers,
322 .writepage = nfs_writepage,
323 .writepages = nfs_writepages,
324 .prepare_write = nfs_prepare_write,
325 .commit_write = nfs_commit_write,
326 .invalidatepage = nfs_invalidate_page,
327 .releasepage = nfs_release_page,
328 #ifdef CONFIG_NFS_DIRECTIO
329 .direct_IO = nfs_direct_IO,
334 * Write to a file (through the page cache).
337 nfs_file_write(struct kiocb *iocb, const char __user *buf, size_t count, loff_t pos)
339 struct dentry * dentry = iocb->ki_filp->f_dentry;
340 struct inode * inode = dentry->d_inode;
343 #ifdef CONFIG_NFS_DIRECTIO
344 if (iocb->ki_filp->f_flags & O_DIRECT)
345 return nfs_file_direct_write(iocb, buf, count, pos);
348 dfprintk(VFS, "nfs: write(%s/%s(%ld), %lu@%lu)\n",
349 dentry->d_parent->d_name.name, dentry->d_name.name,
350 inode->i_ino, (unsigned long) count, (unsigned long) pos);
353 if (IS_SWAPFILE(inode))
356 * O_APPEND implies that we must revalidate the file length.
358 if (iocb->ki_filp->f_flags & O_APPEND) {
359 result = nfs_revalidate_file_size(inode, iocb->ki_filp);
368 nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, count);
369 result = generic_file_aio_write(iocb, buf, count, pos);
374 printk(KERN_INFO "NFS: attempt to write to active swap file!\n");
378 static int do_getlk(struct file *filp, int cmd, struct file_lock *fl)
380 struct file_lock cfl;
381 struct inode *inode = filp->f_mapping->host;
385 /* Try local locking first */
386 if (posix_test_lock(filp, fl, &cfl)) {
387 fl->fl_start = cfl.fl_start;
388 fl->fl_end = cfl.fl_end;
389 fl->fl_type = cfl.fl_type;
390 fl->fl_pid = cfl.fl_pid;
394 if (nfs_have_delegation(inode, FMODE_READ))
397 if (NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM)
400 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
405 fl->fl_type = F_UNLCK;
409 static int do_vfs_lock(struct file *file, struct file_lock *fl)
412 switch (fl->fl_flags & (FL_POSIX|FL_FLOCK)) {
414 res = posix_lock_file_wait(file, fl);
417 res = flock_lock_file_wait(file, fl);
423 printk(KERN_WARNING "%s: VFS is out of sync with lock manager!\n",
428 static int do_unlk(struct file *filp, int cmd, struct file_lock *fl)
430 struct inode *inode = filp->f_mapping->host;
434 * Flush all pending writes before doing anything
437 nfs_sync_mapping(filp->f_mapping);
439 /* NOTE: special case
440 * If we're signalled while cleaning up locks on process exit, we
441 * still need to complete the unlock.
444 /* Use local locking if mounted with "-onolock" */
445 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM))
446 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
448 status = do_vfs_lock(filp, fl);
453 static int do_setlk(struct file *filp, int cmd, struct file_lock *fl)
455 struct inode *inode = filp->f_mapping->host;
459 * Flush all pending writes before doing anything
462 status = nfs_sync_mapping(filp->f_mapping);
467 /* Use local locking if mounted with "-onolock" */
468 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM)) {
469 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
470 /* If we were signalled we still need to ensure that
471 * we clean up any state on the server. We therefore
472 * record the lock call as having succeeded in order to
473 * ensure that locks_remove_posix() cleans it out when
476 if (status == -EINTR || status == -ERESTARTSYS)
477 do_vfs_lock(filp, fl);
479 status = do_vfs_lock(filp, fl);
484 * Make sure we clear the cache whenever we try to get the lock.
485 * This makes locking act as a cache coherency point.
487 nfs_sync_mapping(filp->f_mapping);
488 nfs_zap_caches(inode);
494 * Lock a (portion of) a file
496 static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl)
498 struct inode * inode = filp->f_mapping->host;
500 dprintk("NFS: nfs_lock(f=%s/%ld, t=%x, fl=%x, r=%Ld:%Ld)\n",
501 inode->i_sb->s_id, inode->i_ino,
502 fl->fl_type, fl->fl_flags,
503 (long long)fl->fl_start, (long long)fl->fl_end);
504 nfs_inc_stats(inode, NFSIOS_VFSLOCK);
506 /* No mandatory locks over NFS */
507 if ((inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID &&
508 fl->fl_type != F_UNLCK)
512 return do_getlk(filp, cmd, fl);
513 if (fl->fl_type == F_UNLCK)
514 return do_unlk(filp, cmd, fl);
515 return do_setlk(filp, cmd, fl);
519 * Lock a (portion of) a file
521 static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl)
523 dprintk("NFS: nfs_flock(f=%s/%ld, t=%x, fl=%x)\n",
524 filp->f_dentry->d_inode->i_sb->s_id,
525 filp->f_dentry->d_inode->i_ino,
526 fl->fl_type, fl->fl_flags);
529 * No BSD flocks over NFS allowed.
530 * Note: we could try to fake a POSIX lock request here by
531 * using ((u32) filp | 0x80000000) or some such as the pid.
532 * Not sure whether that would be unique, though, or whether
533 * that would break in other places.
535 if (!(fl->fl_flags & FL_FLOCK))
538 /* We're simulating flock() locks using posix locks on the server */
539 fl->fl_owner = (fl_owner_t)filp;
541 fl->fl_end = OFFSET_MAX;
543 if (fl->fl_type == F_UNLCK)
544 return do_unlk(filp, cmd, fl);
545 return do_setlk(filp, cmd, fl);