Mark all NFS and xattr functions as PF_FSTRANS

Prevent deadlocks by disabling direct reclaim during all NFS and
xattr calls.  This is related to 40d06e3.

Signed-off-by: Brian Behlendorf <[email protected]>
Issue #3225

module/zfs/zpl_export.c

@@ -39,6 +39,7 @@ zpl_encode_fh(struct dentry *dentry, __u32 *fh, int *max_len, int connectable)
 {
 	struct inode *ip = dentry->d_inode;
 #endif /* HAVE_ENCODE_FH_WITH_INODE */
+	fstrans_cookie_t cookie;
 	fid_t *fid = (fid_t *)fh;
 	int len_bytes, rc;
 
@@ -48,12 +49,14 @@ zpl_encode_fh(struct dentry *dentry, __u32 *fh, int *max_len, int connectable)
 		return (255);
 
 	fid->fid_len = len_bytes - offsetof(fid_t, fid_data);
+	cookie = spl_fstrans_mark();
 
 	if (zfsctl_is_node(ip))
 		rc = zfsctl_fid(ip, fid);
 	else
 		rc = zfs_fid(ip, fid);
 
+	spl_fstrans_unmark(cookie);
 	len_bytes = offsetof(fid_t, fid_data) + fid->fid_len;
 	*max_len = roundup(len_bytes, sizeof (__u32)) / sizeof (__u32);
 
@@ -84,6 +87,7 @@ zpl_fh_to_dentry(struct super_block *sb, struct fid *fh,
     int fh_len, int fh_type)
 {
 	fid_t *fid = (fid_t *)fh;
+	fstrans_cookie_t cookie;
 	struct inode *ip;
 	int len_bytes, rc;
 
@@ -94,7 +98,9 @@ zpl_fh_to_dentry(struct super_block *sb, struct fid *fh,
 	    len_bytes < offsetof(fid_t, fid_data) + fid->fid_len)
 		return (ERR_PTR(-EINVAL));
 
+	cookie = spl_fstrans_mark();
 	rc = zfs_vget(sb, &ip, fid);
+	spl_fstrans_unmark(cookie);
 
 	if (rc != 0)
 		return (ERR_PTR(-rc));
@@ -108,11 +114,14 @@ static struct dentry *
 zpl_get_parent(struct dentry *child)
 {
 	cred_t *cr = CRED();
+	fstrans_cookie_t cookie;
 	struct inode *ip;
 	int error;
 
 	crhold(cr);
+	cookie = spl_fstrans_mark();
 	error = -zfs_lookup(child->d_inode, "..", &ip, 0, cr, NULL, NULL);
+	spl_fstrans_unmark(cookie);
 	crfree(cr);
 	ASSERT3S(error, <=, 0);
 
@@ -127,10 +136,13 @@ static int
 zpl_commit_metadata(struct inode *inode)
 {
 	cred_t *cr = CRED();
+	fstrans_cookie_t cookie;
 	int error;
 
 	crhold(cr);
+	cookie = spl_fstrans_mark();
 	error = -zfs_fsync(inode, 0, cr);
+	spl_fstrans_unmark(cookie);
 	crfree(cr);
 	ASSERT3S(error, <=, 0);
 

module/zfs/zpl_xattr.c

@@ -209,9 +209,11 @@ zpl_xattr_list(struct dentry *dentry, char *buffer, size_t buffer_size)
 	zfs_sb_t *zsb = ZTOZSB(zp);
 	xattr_filldir_t xf = { buffer_size, 0, buffer, dentry->d_inode };
 	cred_t *cr = CRED();
+	fstrans_cookie_t cookie;
 	int error = 0;
 
 	crhold(cr);
+	cookie = spl_fstrans_mark();
 	rw_enter(&zp->z_xattr_lock, RW_READER);
 
 	if (zsb->z_use_sa && zp->z_is_sa) {
@@ -228,6 +230,7 @@ zpl_xattr_list(struct dentry *dentry, char *buffer, size_t buffer_size)
 out:
 
 	rw_exit(&zp->z_xattr_lock);
+	spl_fstrans_unmark(cookie);
 	crfree(cr);
 
 	return (error);
@@ -337,12 +340,15 @@ zpl_xattr_get(struct inode *ip, const char *name, void *value, size_t size)
 {
 	znode_t *zp = ITOZ(ip);
 	cred_t *cr = CRED();
+	fstrans_cookie_t cookie;
 	int error;
 
 	crhold(cr);
+	cookie = spl_fstrans_mark();
 	rw_enter(&zp->z_xattr_lock, RW_READER);
 	error = __zpl_xattr_get(ip, name, value, size, cr);
 	rw_exit(&zp->z_xattr_lock);
+	spl_fstrans_unmark(cookie);
 	crfree(cr);
 
 	return (error);
@@ -482,9 +488,11 @@ zpl_xattr_set(struct inode *ip, const char *name, const void *value,
 	znode_t *zp = ITOZ(ip);
 	zfs_sb_t *zsb = ZTOZSB(zp);
 	cred_t *cr = CRED();
+	fstrans_cookie_t cookie;
 	int error;
 
 	crhold(cr);
+	cookie = spl_fstrans_mark();
 	rw_enter(&ITOZ(ip)->z_xattr_lock, RW_WRITER);
 
 	/*
@@ -522,6 +530,7 @@ zpl_xattr_set(struct inode *ip, const char *name, const void *value,
 	error = zpl_xattr_set_dir(ip, name, value, size, flags, cr);
 out:
 	rw_exit(&ITOZ(ip)->z_xattr_lock);
+	spl_fstrans_unmark(cookie);
 	crfree(cr);
 	ASSERT3S(error, <=, 0);