From 5fcc60c3a05bf417229fba715e7aec52bf6717fb Mon Sep 17 00:00:00 2001 From: "David M. Richter" Date: Wed, 23 Apr 2008 16:28:59 -0400 Subject: leases: fix a return-value mixup Fixes a return-value mixup from 85c59580b30c82aa771aa33b37217a6b6851bc14 "locks: Fix potential OOPS in generic_setlease()", in which -ENOMEM replaced what had been intended to stay -EAGAIN in the variable "error". Signed-off-by: David M. Richter Signed-off-by: J. Bruce Fields --- fs/locks.c | 1 + 1 file changed, 1 insertion(+) (limited to 'fs/locks.c') diff --git a/fs/locks.c b/fs/locks.c index 592faadbcec1..b9f3a0bed300 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -1404,6 +1404,7 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp) rdlease_count++; } + error = -EAGAIN; if ((arg == F_RDLCK && (wrlease_count > 0)) || (arg == F_WRLCK && ((rdlease_count + wrlease_count) > 0))) goto out; -- cgit v1.2.2 From 288b2fd8251cb0bcb14b8a93755ef9c78de70e0f Mon Sep 17 00:00:00 2001 From: "David M. Richter" Date: Wed, 23 Apr 2008 16:29:00 -0400 Subject: leases: when unlocking, skip locking-related steps In generic_setlease(), we don't need to allocate a new struct file_lock or check for readers or writers when called with F_UNLCK. Signed-off-by: David M. Richter Signed-off-by: J. Bruce Fields --- fs/locks.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-) (limited to 'fs/locks.c') diff --git a/fs/locks.c b/fs/locks.c index b9f3a0bed300..da1d0ddb4abd 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -1367,18 +1367,20 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp) lease = *flp; - error = -EAGAIN; - if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0)) - goto out; - if ((arg == F_WRLCK) - && ((atomic_read(&dentry->d_count) > 1) - || (atomic_read(&inode->i_count) > 1))) - goto out; + if (arg != F_UNLCK) { + error = -EAGAIN; + if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0)) + goto out; + if ((arg == F_WRLCK) + && ((atomic_read(&dentry->d_count) > 1) + || (atomic_read(&inode->i_count) > 1))) + goto out; - error = -ENOMEM; - new_fl = locks_alloc_lock(); - if (new_fl == NULL) - goto out; + error = -ENOMEM; + new_fl = locks_alloc_lock(); + if (new_fl == NULL) + goto out; + } /* * At this point, we know that if there is an exclusive -- cgit v1.2.2 From 190855576743a510219fc67886dace29b825d8cb Mon Sep 17 00:00:00 2001 From: "David M. Richter" Date: Wed, 23 Apr 2008 16:29:01 -0400 Subject: leases: move lock allocation earlier in generic_setlease() In generic_setlease(), the struct file_lock is allocated after tests for the presence of conflicting readers/writers is done, despite the fact that the allocation might block; this patch moves the allocation earlier. A subsequent set of patches will rely on this behavior to properly serialize between a modified __break_lease() and generic_setlease(). Signed-off-by: David M. Richter Signed-off-by: J. Bruce Fields --- fs/locks.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'fs/locks.c') diff --git a/fs/locks.c b/fs/locks.c index da1d0ddb4abd..6a132cd4fa57 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -1368,6 +1368,11 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp) lease = *flp; if (arg != F_UNLCK) { + error = -ENOMEM; + new_fl = locks_alloc_lock(); + if (new_fl == NULL) + goto out; + error = -EAGAIN; if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0)) goto out; @@ -1375,11 +1380,6 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp) && ((atomic_read(&dentry->d_count) > 1) || (atomic_read(&inode->i_count) > 1))) goto out; - - error = -ENOMEM; - new_fl = locks_alloc_lock(); - if (new_fl == NULL) - goto out; } /* -- cgit v1.2.2 From 9d91cdcc0cce3186742f38e7352459b2087fbb86 Mon Sep 17 00:00:00 2001 From: "David M. Richter" Date: Wed, 23 Apr 2008 16:29:02 -0400 Subject: leases: remove unneeded variable from fcntl_setlease(). fcntl_setlease() has a struct dentry* that is used only once; this patch removes it. Signed-off-by: David M. Richter Signed-off-by: J. Bruce Fields --- fs/locks.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'fs/locks.c') diff --git a/fs/locks.c b/fs/locks.c index 6a132cd4fa57..2e0fa661e423 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -1493,8 +1493,7 @@ EXPORT_SYMBOL_GPL(vfs_setlease); int fcntl_setlease(unsigned int fd, struct file *filp, long arg) { struct file_lock fl, *flp = &fl; - struct dentry *dentry = filp->f_path.dentry; - struct inode *inode = dentry->d_inode; + struct inode *inode = filp->f_path.dentry->d_inode; int error; locks_init_lock(&fl); -- cgit v1.2.2 From 1a747ee0cc11a198f9e2435add821bd0dfedb7c1 Mon Sep 17 00:00:00 2001 From: "J. Bruce Fields" Date: Thu, 24 Apr 2008 10:08:22 -0400 Subject: locks: don't call ->copy_lock methods on return of conflicting locks The file_lock structure is used both as a heavy-weight representation of an active lock, with pointers to reference-counted structures, etc., and as a simple container for parameters that describe a file lock. The conflicting lock returned from __posix_lock_file is an example of the latter; so don't call the filesystem or lock manager callbacks when copying to it. This also saves the need for an unnecessary locks_init_lock in the nfsv4 server. Thanks to Trond for pointing out the error. Signed-off-by: J. Bruce Fields Cc: Trond Myklebust --- fs/locks.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/locks.c') diff --git a/fs/locks.c b/fs/locks.c index 2e0fa661e423..e1ea2fe03681 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -224,7 +224,7 @@ static void locks_copy_private(struct file_lock *new, struct file_lock *fl) /* * Initialize a new lock from an existing file_lock structure. */ -static void __locks_copy_lock(struct file_lock *new, const struct file_lock *fl) +void __locks_copy_lock(struct file_lock *new, const struct file_lock *fl) { new->fl_owner = fl->fl_owner; new->fl_pid = fl->fl_pid; @@ -833,7 +833,7 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str if (!posix_locks_conflict(request, fl)) continue; if (conflock) - locks_copy_lock(conflock, fl); + __locks_copy_lock(conflock, fl); error = -EAGAIN; if (!(request->fl_flags & FL_SLEEP)) goto out; -- cgit v1.2.2