fuse: invalidation reverse calls
Add notification messages that allow the filesystem to invalidate VFS
caches.
Two notifications are added:
1) inode invalidation
- invalidate cached attributes
- invalidate a range of pages in the page cache (this is optional)
2) dentry invalidation
- try to invalidate a subtree in the dentry cache
Care must be taken while accessing the 'struct super_block' for the
mount, as it can go away while an invalidation is in progress. To
prevent this, introduce a rw-semaphore, that is taken for read during
the invalidation and taken for write in the ->kill_sb callback.
Cc: Csaba Henk <csaba@gluster.com>
Cc: Anand Avati <avati@zresearch.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 6cc501b..f91ccc4 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -206,7 +206,7 @@
BUG();
}
-static int fuse_inode_eq(struct inode *inode, void *_nodeidp)
+int fuse_inode_eq(struct inode *inode, void *_nodeidp)
{
u64 nodeid = *(u64 *) _nodeidp;
if (get_node_id(inode) == nodeid)
@@ -257,6 +257,31 @@
return inode;
}
+int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid,
+ loff_t offset, loff_t len)
+{
+ struct inode *inode;
+ pgoff_t pg_start;
+ pgoff_t pg_end;
+
+ inode = ilookup5(sb, nodeid, fuse_inode_eq, &nodeid);
+ if (!inode)
+ return -ENOENT;
+
+ fuse_invalidate_attr(inode);
+ if (offset >= 0) {
+ pg_start = offset >> PAGE_CACHE_SHIFT;
+ if (len <= 0)
+ pg_end = -1;
+ else
+ pg_end = (offset + len - 1) >> PAGE_CACHE_SHIFT;
+ invalidate_inode_pages2_range(inode->i_mapping,
+ pg_start, pg_end);
+ }
+ iput(inode);
+ return 0;
+}
+
static void fuse_umount_begin(struct super_block *sb)
{
fuse_abort_conn(get_fuse_conn_super(sb));
@@ -480,6 +505,7 @@
memset(fc, 0, sizeof(*fc));
spin_lock_init(&fc->lock);
mutex_init(&fc->inst_mutex);
+ init_rwsem(&fc->killsb);
atomic_set(&fc->count, 1);
init_waitqueue_head(&fc->waitq);
init_waitqueue_head(&fc->blocked_waitq);
@@ -862,6 +888,7 @@
fuse_conn_init(fc);
fc->dev = sb->s_dev;
+ fc->sb = sb;
err = fuse_bdi_init(fc, sb);
if (err)
goto err_put_conn;
@@ -948,12 +975,25 @@
return get_sb_nodev(fs_type, flags, raw_data, fuse_fill_super, mnt);
}
+static void fuse_kill_sb_anon(struct super_block *sb)
+{
+ struct fuse_conn *fc = get_fuse_conn_super(sb);
+
+ if (fc) {
+ down_write(&fc->killsb);
+ fc->sb = NULL;
+ up_write(&fc->killsb);
+ }
+
+ kill_anon_super(sb);
+}
+
static struct file_system_type fuse_fs_type = {
.owner = THIS_MODULE,
.name = "fuse",
.fs_flags = FS_HAS_SUBTYPE,
.get_sb = fuse_get_sb,
- .kill_sb = kill_anon_super,
+ .kill_sb = fuse_kill_sb_anon,
};
#ifdef CONFIG_BLOCK
@@ -965,11 +1005,24 @@
mnt);
}
+static void fuse_kill_sb_blk(struct super_block *sb)
+{
+ struct fuse_conn *fc = get_fuse_conn_super(sb);
+
+ if (fc) {
+ down_write(&fc->killsb);
+ fc->sb = NULL;
+ up_write(&fc->killsb);
+ }
+
+ kill_block_super(sb);
+}
+
static struct file_system_type fuseblk_fs_type = {
.owner = THIS_MODULE,
.name = "fuseblk",
.get_sb = fuse_get_sb_blk,
- .kill_sb = kill_block_super,
+ .kill_sb = fuse_kill_sb_blk,
.fs_flags = FS_REQUIRES_DEV | FS_HAS_SUBTYPE,
};