diff options
| author |   Greg Farnum <gregf@hq.newdream.net> | 2010-09-17 10:24:02 -0700 |
|---|---|---|
| committer |   Sage Weil <sage@newdream.net> | 2010-10-20 15:38:17 -0700 |
| commit | fca4451acfdcf894154e4809529ca28a09db88ff (patch) | |
| tree | 446381c8e8c7b592b47c2e50c32b1e40817fcfe1 /fs/ceph/locks.c | |
| parent | ceph: add pagelist_reserve, pagelist_truncate, pagelist_set_cursor (diff) | |
| download | linux-dev-fca4451acfdcf894154e4809529ca28a09db88ff.tar.xz linux-dev-fca4451acfdcf894154e4809529ca28a09db88ff.zip | |
ceph: preallocate flock state without locks held
When the lock_kernel() turns into lock_flocks() and a spinlock, we won't
be able to do allocations with the lock held. Preallocate space without
the lock, and retry if the lock state changes out from underneath us.
Signed-off-by: Greg Farnum <gregf@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
Diffstat (limited to 'fs/ceph/locks.c')
| -rw-r--r-- | fs/ceph/locks.c | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/fs/ceph/locks.c b/fs/ceph/locks.c index 087afe9ca367..40abde93c345 100644 --- a/fs/ceph/locks.c +++ b/fs/ceph/locks.c @@ -181,8 +181,9 @@ void ceph_count_locks(struct inode *inode, int *fcntl_count, int *flock_count) * Encode the flock and fcntl locks for the given inode into the pagelist. * Format is: #fcntl locks, sequential fcntl locks, #flock locks, * sequential flock locks. - * Must be called with BLK already held, and the lock numbers should have - * been gathered under the same lock holding window. + * Must be called with lock_flocks() already held. + * If we encounter more of a specific lock type than expected, + * we return the value 1. */ int ceph_encode_locks(struct inode *inode, struct ceph_pagelist *pagelist, int num_fcntl_locks, int num_flock_locks) @@ -190,6 +191,8 @@ int ceph_encode_locks(struct inode *inode, struct ceph_pagelist *pagelist, struct file_lock *lock; struct ceph_filelock cephlock; int err = 0; + int seen_fcntl = 0; + int seen_flock = 0; dout("encoding %d flock and %d fcntl locks", num_flock_locks, num_fcntl_locks); @@ -198,6 +201,11 @@ int ceph_encode_locks(struct inode *inode, struct ceph_pagelist *pagelist, goto fail; for (lock = inode->i_flock; lock != NULL; lock = lock->fl_next) { if (lock->fl_flags & FL_POSIX) { + ++seen_fcntl; + if (seen_fcntl > num_fcntl_locks) { + err = -ENOSPC; + goto fail; + } err = lock_to_ceph_filelock(lock, &cephlock); if (err) goto fail; @@ -213,6 +221,11 @@ int ceph_encode_locks(struct inode *inode, struct ceph_pagelist *pagelist, goto fail; for (lock = inode->i_flock; lock != NULL; lock = lock->fl_next) { if (lock->fl_flags & FL_FLOCK) { + ++seen_flock; + if (seen_flock > num_flock_locks) { + err = -ENOSPC; + goto fail; + } err = lock_to_ceph_filelock(lock, &cephlock); if (err) goto fail; |