Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse fix from Miklos Szeredi:
"This makes sure userspace filesystems are not broken by the parallel
lookups and readdir feature"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
fuse: serialize dirops by default
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index ccd4971..264f07c 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -341,8 +341,10 @@
struct dentry *newent;
bool outarg_valid = true;
+ fuse_lock_inode(dir);
err = fuse_lookup_name(dir->i_sb, get_node_id(dir), &entry->d_name,
&outarg, &inode);
+ fuse_unlock_inode(dir);
if (err == -ENOENT) {
outarg_valid = false;
err = 0;
@@ -1341,7 +1343,9 @@
fuse_read_fill(req, file, ctx->pos, PAGE_SIZE,
FUSE_READDIR);
}
+ fuse_lock_inode(inode);
fuse_request_send(fc, req);
+ fuse_unlock_inode(inode);
nbytes = req->out.args[0].size;
err = req->out.h.error;
fuse_put_request(fc, req);
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index eddbe02..929c383 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -110,6 +110,9 @@
/** Miscellaneous bits describing inode state */
unsigned long state;
+
+ /** Lock for serializing lookup and readdir for back compatibility*/
+ struct mutex mutex;
};
/** FUSE inode state bits */
@@ -540,6 +543,9 @@
/** write-back cache policy (default is write-through) */
unsigned writeback_cache:1;
+ /** allow parallel lookups and readdir (default is serialized) */
+ unsigned parallel_dirops:1;
+
/*
* The following bitfields are only for optimization purposes
* and hence races in setting them will not cause malfunction
@@ -956,4 +962,7 @@
void fuse_set_initialized(struct fuse_conn *fc);
+void fuse_unlock_inode(struct inode *inode);
+void fuse_lock_inode(struct inode *inode);
+
#endif /* _FS_FUSE_I_H */
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 1ce6766..9961d843 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -97,6 +97,7 @@
INIT_LIST_HEAD(&fi->queued_writes);
INIT_LIST_HEAD(&fi->writepages);
init_waitqueue_head(&fi->page_waitq);
+ mutex_init(&fi->mutex);
fi->forget = fuse_alloc_forget();
if (!fi->forget) {
kmem_cache_free(fuse_inode_cachep, inode);
@@ -117,6 +118,7 @@
struct fuse_inode *fi = get_fuse_inode(inode);
BUG_ON(!list_empty(&fi->write_files));
BUG_ON(!list_empty(&fi->queued_writes));
+ mutex_destroy(&fi->mutex);
kfree(fi->forget);
call_rcu(&inode->i_rcu, fuse_i_callback);
}
@@ -351,6 +353,18 @@
return 0;
}
+void fuse_lock_inode(struct inode *inode)
+{
+ if (!get_fuse_conn(inode)->parallel_dirops)
+ mutex_lock(&get_fuse_inode(inode)->mutex);
+}
+
+void fuse_unlock_inode(struct inode *inode)
+{
+ if (!get_fuse_conn(inode)->parallel_dirops)
+ mutex_unlock(&get_fuse_inode(inode)->mutex);
+}
+
static void fuse_umount_begin(struct super_block *sb)
{
fuse_abort_conn(get_fuse_conn_super(sb));
@@ -898,6 +912,8 @@
fc->async_dio = 1;
if (arg->flags & FUSE_WRITEBACK_CACHE)
fc->writeback_cache = 1;
+ if (arg->flags & FUSE_PARALLEL_DIROPS)
+ fc->parallel_dirops = 1;
if (arg->time_gran && arg->time_gran <= 1000000000)
fc->sb->s_time_gran = arg->time_gran;
} else {
@@ -928,7 +944,8 @@
FUSE_SPLICE_WRITE | FUSE_SPLICE_MOVE | FUSE_SPLICE_READ |
FUSE_FLOCK_LOCKS | FUSE_IOCTL_DIR | FUSE_AUTO_INVAL_DATA |
FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO |
- FUSE_WRITEBACK_CACHE | FUSE_NO_OPEN_SUPPORT;
+ FUSE_WRITEBACK_CACHE | FUSE_NO_OPEN_SUPPORT |
+ FUSE_PARALLEL_DIROPS;
req->in.h.opcode = FUSE_INIT;
req->in.numargs = 1;
req->in.args[0].size = sizeof(*arg);
diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h
index 5974fae..27e1736 100644
--- a/include/uapi/linux/fuse.h
+++ b/include/uapi/linux/fuse.h
@@ -105,6 +105,9 @@
*
* 7.24
* - add FUSE_LSEEK for SEEK_HOLE and SEEK_DATA support
+ *
+ * 7.25
+ * - add FUSE_PARALLEL_DIROPS
*/
#ifndef _LINUX_FUSE_H
@@ -140,7 +143,7 @@
#define FUSE_KERNEL_VERSION 7
/** Minor version number of this interface */
-#define FUSE_KERNEL_MINOR_VERSION 24
+#define FUSE_KERNEL_MINOR_VERSION 25
/** The node ID of the root inode */
#define FUSE_ROOT_ID 1
@@ -234,6 +237,7 @@
* FUSE_ASYNC_DIO: asynchronous direct I/O submission
* FUSE_WRITEBACK_CACHE: use writeback cache for buffered writes
* FUSE_NO_OPEN_SUPPORT: kernel supports zero-message opens
+ * FUSE_PARALLEL_DIROPS: allow parallel lookups and readdir
*/
#define FUSE_ASYNC_READ (1 << 0)
#define FUSE_POSIX_LOCKS (1 << 1)
@@ -253,6 +257,7 @@
#define FUSE_ASYNC_DIO (1 << 15)
#define FUSE_WRITEBACK_CACHE (1 << 16)
#define FUSE_NO_OPEN_SUPPORT (1 << 17)
+#define FUSE_PARALLEL_DIROPS (1 << 18)
/**
* CUSE INIT request/reply flags
