summaryrefslogtreecommitdiffstats
path: root/fs/fuse/inode.c
diff options
context:
space:
mode:
authorMiklos Szeredi2006-10-17 09:10:06 +0200
committerLinus Torvalds2006-10-17 17:18:45 +0200
commit9ffbb9162312fd8113037cb3d94f787f06bbfa9a (patch)
treea8194bb542dcda56271b44d7de23f2a72ecac900 /fs/fuse/inode.c
parent[PATCH] sx: fix user-visible typo (devic) (diff)
downloadkernel-qcow2-linux-9ffbb9162312fd8113037cb3d94f787f06bbfa9a.tar.gz
kernel-qcow2-linux-9ffbb9162312fd8113037cb3d94f787f06bbfa9a.tar.xz
kernel-qcow2-linux-9ffbb9162312fd8113037cb3d94f787f06bbfa9a.zip
[PATCH] fuse: fix hang on SMP
Fuse didn't always call i_size_write() with i_mutex held which caused rare hangs on SMP/32bit. This bug has been present since fuse-2.2, well before being merged into mainline. The simplest solution is to protect i_size_write() with the per-connection spinlock. Using i_mutex for this purpose would require some restructuring of the code and I'm not even sure it's always safe to acquire i_mutex in all places i_size needs to be set. Since most of vmtruncate is already duplicated for other reasons, duplicate the remaining part as well, making all i_size_write() calls internal to fuse. Using i_size_write() was unnecessary in fuse_init_inode(), since this function is only called on a newly created locked inode. Reported by a few people over the years, but special thanks to Dana Henriksen who was persistent enough in helping me debug it. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'fs/fuse/inode.c')
-rw-r--r--fs/fuse/inode.c5
1 files changed, 4 insertions, 1 deletions
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 7d0a9aee01f2..8e106163aaed 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -109,6 +109,7 @@ static int fuse_remount_fs(struct super_block *sb, int *flags, char *data)
void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr)
{
+ struct fuse_conn *fc = get_fuse_conn(inode);
if (S_ISREG(inode->i_mode) && i_size_read(inode) != attr->size)
invalidate_inode_pages(inode->i_mapping);
@@ -117,7 +118,9 @@ void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr)
inode->i_nlink = attr->nlink;
inode->i_uid = attr->uid;
inode->i_gid = attr->gid;
+ spin_lock(&fc->lock);
i_size_write(inode, attr->size);
+ spin_unlock(&fc->lock);
inode->i_blocks = attr->blocks;
inode->i_atime.tv_sec = attr->atime;
inode->i_atime.tv_nsec = attr->atimensec;
@@ -130,7 +133,7 @@ void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr)
static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr)
{
inode->i_mode = attr->mode & S_IFMT;
- i_size_write(inode, attr->size);
+ inode->i_size = attr->size;
if (S_ISREG(inode->i_mode)) {
fuse_init_common(inode);
fuse_init_file_inode(inode);