Commit f6297acf authored by Trond Myklebust's avatar Trond Myklebust Committed by Linus Torvalds

[PATCH] Fix posix file locking (9/9)

NFSv2/v3: Fix up a race in the case where the user presses ^C while a
   process is in the middle of setting up a posix lock. In case the
   server registered our lock, we need to make sure that it gets
   cleaned up during the resulting file close().
Signed-off-by: default avatarTrond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent ffc13a38
...@@ -288,6 +288,90 @@ nfs_file_write(struct kiocb *iocb, const char __user *buf, size_t count, loff_t ...@@ -288,6 +288,90 @@ nfs_file_write(struct kiocb *iocb, const char __user *buf, size_t count, loff_t
goto out; goto out;
} }
static int do_getlk(struct file *filp, int cmd, struct file_lock *fl)
{
struct inode *inode = filp->f_mapping->host;
int status;
lock_kernel();
status = NFS_PROTO(inode)->lock(filp, cmd, fl);
unlock_kernel();
return status;
}
static int do_unlk(struct file *filp, int cmd, struct file_lock *fl)
{
struct inode *inode = filp->f_mapping->host;
sigset_t oldset;
int status;
rpc_clnt_sigmask(NFS_CLIENT(inode), &oldset);
/*
* Flush all pending writes before doing anything
* with locks..
*/
filemap_fdatawrite(filp->f_mapping);
down(&inode->i_sem);
nfs_wb_all(inode);
up(&inode->i_sem);
filemap_fdatawait(filp->f_mapping);
/* NOTE: special case
* If we're signalled while cleaning up locks on process exit, we
* still need to complete the unlock.
*/
lock_kernel();
status = NFS_PROTO(inode)->lock(filp, cmd, fl);
rpc_clnt_sigunmask(NFS_CLIENT(inode), &oldset);
return status;
}
static int do_setlk(struct file *filp, int cmd, struct file_lock *fl)
{
struct inode *inode = filp->f_mapping->host;
int status;
/*
* Flush all pending writes before doing anything
* with locks..
*/
status = filemap_fdatawrite(filp->f_mapping);
if (status == 0) {
down(&inode->i_sem);
status = nfs_wb_all(inode);
up(&inode->i_sem);
if (status == 0)
status = filemap_fdatawait(filp->f_mapping);
}
if (status < 0)
return status;
lock_kernel();
status = NFS_PROTO(inode)->lock(filp, cmd, fl);
/* If we were signalled we still need to ensure that
* we clean up any state on the server. We therefore
* record the lock call as having succeeded in order to
* ensure that locks_remove_posix() cleans it out when
* the process exits.
*/
if (status == -EINTR || status == -ERESTARTSYS)
posix_lock_file(filp, fl);
unlock_kernel();
if (status < 0)
return status;
/*
* Make sure we clear the cache whenever we try to get the lock.
* This makes locking act as a cache coherency point.
*/
filemap_fdatawrite(filp->f_mapping);
down(&inode->i_sem);
nfs_wb_all(inode); /* we may have slept */
up(&inode->i_sem);
filemap_fdatawait(filp->f_mapping);
nfs_zap_caches(inode);
return 0;
}
/* /*
* Lock a (portion of) a file * Lock a (portion of) a file
*/ */
...@@ -295,8 +379,6 @@ int ...@@ -295,8 +379,6 @@ int
nfs_lock(struct file *filp, int cmd, struct file_lock *fl) nfs_lock(struct file *filp, int cmd, struct file_lock *fl)
{ {
struct inode * inode = filp->f_mapping->host; struct inode * inode = filp->f_mapping->host;
int status = 0;
int status2;
dprintk("NFS: nfs_lock(f=%s/%ld, t=%x, fl=%x, r=%Ld:%Ld)\n", dprintk("NFS: nfs_lock(f=%s/%ld, t=%x, fl=%x, r=%Ld:%Ld)\n",
inode->i_sb->s_id, inode->i_ino, inode->i_sb->s_id, inode->i_ino,
...@@ -314,8 +396,8 @@ nfs_lock(struct file *filp, int cmd, struct file_lock *fl) ...@@ -314,8 +396,8 @@ nfs_lock(struct file *filp, int cmd, struct file_lock *fl)
/* Fake OK code if mounted without NLM support */ /* Fake OK code if mounted without NLM support */
if (NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM) { if (NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM) {
if (IS_GETLK(cmd)) if (IS_GETLK(cmd))
status = LOCK_USE_CLNT; return LOCK_USE_CLNT;
goto out_ok; return 0;
} }
} }
...@@ -329,42 +411,9 @@ nfs_lock(struct file *filp, int cmd, struct file_lock *fl) ...@@ -329,42 +411,9 @@ nfs_lock(struct file *filp, int cmd, struct file_lock *fl)
if (!fl->fl_owner || !(fl->fl_flags & FL_POSIX)) if (!fl->fl_owner || !(fl->fl_flags & FL_POSIX))
return -ENOLCK; return -ENOLCK;
/* if (IS_GETLK(cmd))
* Flush all pending writes before doing anything return do_getlk(filp, cmd, fl);
* with locks.. if (fl->fl_type == F_UNLCK)
*/ return do_unlk(filp, cmd, fl);
status = filemap_fdatawrite(filp->f_mapping); return do_setlk(filp, cmd, fl);
down(&inode->i_sem);
status2 = nfs_wb_all(inode);
if (!status)
status = status2;
up(&inode->i_sem);
status2 = filemap_fdatawait(filp->f_mapping);
if (!status)
status = status2;
if (status < 0)
return status;
lock_kernel();
status = NFS_PROTO(inode)->lock(filp, cmd, fl);
unlock_kernel();
if (status < 0)
return status;
status = 0;
/*
* Make sure we clear the cache whenever we try to get the lock.
* This makes locking act as a cache coherency point.
*/
out_ok:
if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
filemap_fdatawrite(filp->f_mapping);
down(&inode->i_sem);
nfs_wb_all(inode); /* we may have slept */
up(&inode->i_sem);
filemap_fdatawait(filp->f_mapping);
nfs_zap_caches(inode);
}
return status;
} }
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