staging: add Lustre file system client support

Lustre is the most deployed distributed file system
in the HPC (High Performance Computing) world. The patch
adds its client side support.

The code is not very clean and needs to live in drivers/staging
for some time for continuing cleanup work. See
drivers/staging/lustre/TODO for details.

The code is based on Lustre master commit faefbfc04

commit faefbfc0460bc00f2ee4c1c1c86aa1e39b9eea49
Author: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Date:   Tue Apr 30 23:05:21 2013 +0400

    LU-3244 utils: tunefs.lustre should preserve virgin label

Plus a few under-review patches on Whamcloud gerrit:
3.8 kernel support:
http://review.whamcloud.com/#change,5973
http://review.whamcloud.com/#change,5974
http://review.whamcloud.com/#change,5768
http://review.whamcloud.com/#change,5781
http://review.whamcloud.com/#change,5763
http://review.whamcloud.com/#change,5613
http://review.whamcloud.com/#change,5655

3.9 kernel support:
http://review.whamcloud.com/#change,5898
http://review.whamcloud.com/#change,5899

Kconfig/Kbuild:
http://review.whamcloud.com/#change,4646
http://review.whamcloud.com/#change,4644

libcfs cleanup:
http://review.whamcloud.com/#change,2831
http://review.whamcloud.com/#change,4775
http://review.whamcloud.com/#change,4776
http://review.whamcloud.com/#change,4777
http://review.whamcloud.com/#change,4778
http://review.whamcloud.com/#change,4779
http://review.whamcloud.com/#change,4780

All starting/trailing whitespaces are removed, to match kernel
coding style. Also ran scripts/cleanfile on all lustre source files.

[maked the Kconfig depend on BROKEN as the recent procfs changes causes
this to fail - gregkh]

Signed-off-by: Peng Tao <tao.peng@emc.com>
Signed-off-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 578 insertions, 0 deletions

diff --git a/drivers/staging/lustre/lustre/llite/xattr.c b/drivers/staging/lustre/lustre/llite/xattr.c
new file mode 100644
index 000000000000..4176264984bb
--- /dev/null
+++ b/drivers/staging/lustre/lustre/llite/xattr.c
@@ -0,0 +1,578 @@
+/*
+ * GPL HEADER START
+ *
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 only,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License version 2 for more details (a copy is included
+ * in the LICENSE file that accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License
+ * version 2 along with this program; If not, see
+ * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ * GPL HEADER END
+ */
+/*
+ * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Use is subject to license terms.
+ *
+ * Copyright (c) 2011, 2012, Intel Corporation.
+ */
+/*
+ * This file is part of Lustre, http://www.lustre.org/
+ * Lustre is a trademark of Sun Microsystems, Inc.
+ */
+
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/selinux.h>
+
+#define DEBUG_SUBSYSTEM S_LLITE
+
+#include <obd_support.h>
+#include <lustre_lite.h>
+#include <lustre_dlm.h>
+#include <lustre_ver.h>
+#include <lustre_eacl.h>
+
+#include "llite_internal.h"
+
+#define XATTR_USER_T	    (1)
+#define XATTR_TRUSTED_T	 (2)
+#define XATTR_SECURITY_T	(3)
+#define XATTR_ACL_ACCESS_T      (4)
+#define XATTR_ACL_DEFAULT_T     (5)
+#define XATTR_LUSTRE_T	  (6)
+#define XATTR_OTHER_T	   (7)
+
+static
+int get_xattr_type(const char *name)
+{
+	if (!strcmp(name, POSIX_ACL_XATTR_ACCESS))
+		return XATTR_ACL_ACCESS_T;
+
+	if (!strcmp(name, POSIX_ACL_XATTR_DEFAULT))
+		return XATTR_ACL_DEFAULT_T;
+
+	if (!strncmp(name, XATTR_USER_PREFIX,
+		     sizeof(XATTR_USER_PREFIX) - 1))
+		return XATTR_USER_T;
+
+	if (!strncmp(name, XATTR_TRUSTED_PREFIX,
+		     sizeof(XATTR_TRUSTED_PREFIX) - 1))
+		return XATTR_TRUSTED_T;
+
+	if (!strncmp(name, XATTR_SECURITY_PREFIX,
+		     sizeof(XATTR_SECURITY_PREFIX) - 1))
+		return XATTR_SECURITY_T;
+
+	if (!strncmp(name, XATTR_LUSTRE_PREFIX,
+		     sizeof(XATTR_LUSTRE_PREFIX) - 1))
+		return XATTR_LUSTRE_T;
+
+	return XATTR_OTHER_T;
+}
+
+static
+int xattr_type_filter(struct ll_sb_info *sbi, int xattr_type)
+{
+	if ((xattr_type == XATTR_ACL_ACCESS_T ||
+	     xattr_type == XATTR_ACL_DEFAULT_T) &&
+	   !(sbi->ll_flags & LL_SBI_ACL))
+		return -EOPNOTSUPP;
+
+	if (xattr_type == XATTR_USER_T && !(sbi->ll_flags & LL_SBI_USER_XATTR))
+		return -EOPNOTSUPP;
+	if (xattr_type == XATTR_TRUSTED_T && !cfs_capable(CFS_CAP_SYS_ADMIN))
+		return -EPERM;
+	if (xattr_type == XATTR_OTHER_T)
+		return -EOPNOTSUPP;
+
+	return 0;
+}
+
+static
+int ll_setxattr_common(struct inode *inode, const char *name,
+		       const void *value, size_t size,
+		       int flags, __u64 valid)
+{
+	struct ll_sb_info *sbi = ll_i2sbi(inode);
+	struct ptlrpc_request *req;
+	int xattr_type, rc;
+	struct obd_capa *oc;
+	posix_acl_xattr_header *new_value = NULL;
+	struct rmtacl_ctl_entry *rce = NULL;
+	ext_acl_xattr_header *acl = NULL;
+	const char *pv = value;
+	ENTRY;
+
+	xattr_type = get_xattr_type(name);
+	rc = xattr_type_filter(sbi, xattr_type);
+	if (rc)
+		RETURN(rc);
+
+	/* b10667: ignore lustre special xattr for now */
+	if ((xattr_type == XATTR_TRUSTED_T && strcmp(name, "trusted.lov") == 0) ||
+	    (xattr_type == XATTR_LUSTRE_T && strcmp(name, "lustre.lov") == 0))
+		RETURN(0);
+
+	/* b15587: ignore security.capability xattr for now */
+	if ((xattr_type == XATTR_SECURITY_T &&
+	    strcmp(name, "security.capability") == 0))
+		RETURN(0);
+
+	/* LU-549:  Disable security.selinux when selinux is disabled */
+	if (xattr_type == XATTR_SECURITY_T && !selinux_is_enabled() &&
+	    strcmp(name, "security.selinux") == 0)
+		RETURN(-EOPNOTSUPP);
+
+#ifdef CONFIG_FS_POSIX_ACL
+	if (sbi->ll_flags & LL_SBI_RMT_CLIENT &&
+	    (xattr_type == XATTR_ACL_ACCESS_T ||
+	    xattr_type == XATTR_ACL_DEFAULT_T)) {
+		rce = rct_search(&sbi->ll_rct, current_pid());
+		if (rce == NULL ||
+		    (rce->rce_ops != RMT_LSETFACL &&
+		    rce->rce_ops != RMT_RSETFACL))
+			RETURN(-EOPNOTSUPP);
+
+		if (rce->rce_ops == RMT_LSETFACL) {
+			struct eacl_entry *ee;
+
+			ee = et_search_del(&sbi->ll_et, current_pid(),
+					   ll_inode2fid(inode), xattr_type);
+			LASSERT(ee != NULL);
+			if (valid & OBD_MD_FLXATTR) {
+				acl = lustre_acl_xattr_merge2ext(
+						(posix_acl_xattr_header *)value,
+						size, ee->ee_acl);
+				if (IS_ERR(acl)) {
+					ee_free(ee);
+					RETURN(PTR_ERR(acl));
+				}
+				size =  CFS_ACL_XATTR_SIZE(\
+						le32_to_cpu(acl->a_count), \
+						ext_acl_xattr);
+				pv = (const char *)acl;
+			}
+			ee_free(ee);
+		} else if (rce->rce_ops == RMT_RSETFACL) {
+			size = lustre_posix_acl_xattr_filter(
+						(posix_acl_xattr_header *)value,
+						size, &new_value);
+			if (unlikely(size < 0))
+				RETURN(size);
+
+			pv = (const char *)new_value;
+		} else
+			RETURN(-EOPNOTSUPP);
+
+		valid |= rce_ops2valid(rce->rce_ops);
+	}
+#endif
+	oc = ll_mdscapa_get(inode);
+	rc = md_setxattr(sbi->ll_md_exp, ll_inode2fid(inode), oc,
+			 valid, name, pv, size, 0, flags, ll_i2suppgid(inode),
+			 &req);
+	capa_put(oc);
+#ifdef CONFIG_FS_POSIX_ACL
+	if (new_value != NULL)
+		lustre_posix_acl_xattr_free(new_value, size);
+	if (acl != NULL)
+		lustre_ext_acl_xattr_free(acl);
+#endif
+	if (rc) {
+		if (rc == -EOPNOTSUPP && xattr_type == XATTR_USER_T) {
+			LCONSOLE_INFO("Disabling user_xattr feature because "
+				      "it is not supported on the server\n");
+			sbi->ll_flags &= ~LL_SBI_USER_XATTR;
+		}
+		RETURN(rc);
+	}
+
+	ptlrpc_req_finished(req);
+	RETURN(0);
+}
+
+int ll_setxattr(struct dentry *dentry, const char *name,
+		const void *value, size_t size, int flags)
+{
+	struct inode *inode = dentry->d_inode;
+
+	LASSERT(inode);
+	LASSERT(name);
+
+	CDEBUG(D_VFSTRACE, "VFS Op:inode=%lu/%u(%p), xattr %s\n",
+	       inode->i_ino, inode->i_generation, inode, name);
+
+	ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_SETXATTR, 1);
+
+	if ((strncmp(name, XATTR_TRUSTED_PREFIX,
+		     sizeof(XATTR_TRUSTED_PREFIX) - 1) == 0 &&
+	     strcmp(name + sizeof(XATTR_TRUSTED_PREFIX) - 1, "lov") == 0) ||
+	    (strncmp(name, XATTR_LUSTRE_PREFIX,
+		     sizeof(XATTR_LUSTRE_PREFIX) - 1) == 0 &&
+	     strcmp(name + sizeof(XATTR_LUSTRE_PREFIX) - 1, "lov") == 0)) {
+		struct lov_user_md *lump = (struct lov_user_md *)value;
+		int rc = 0;
+
+		/* Attributes that are saved via getxattr will always have
+		 * the stripe_offset as 0.  Instead, the MDS should be
+		 * allowed to pick the starting OST index.   b=17846 */
+		if (lump != NULL && lump->lmm_stripe_offset == 0)
+			lump->lmm_stripe_offset = -1;
+
+		if (lump != NULL && S_ISREG(inode->i_mode)) {
+			struct file f;
+			int flags = FMODE_WRITE;
+			int lum_size = (lump->lmm_magic == LOV_USER_MAGIC_V1) ?
+				sizeof(*lump) : sizeof(struct lov_user_md_v3);
+
+			f.f_dentry = dentry;
+			rc = ll_lov_setstripe_ea_info(inode, &f, flags, lump,
+						      lum_size);
+			/* b10667: rc always be 0 here for now */
+			rc = 0;
+		} else if (S_ISDIR(inode->i_mode)) {
+			rc = ll_dir_setstripe(inode, lump, 0);
+		}
+
+		return rc;
+
+	} else if (strcmp(name, XATTR_NAME_LMA) == 0 ||
+		   strcmp(name, XATTR_NAME_LINK) == 0)
+		return 0;
+
+	return ll_setxattr_common(inode, name, value, size, flags,
+				  OBD_MD_FLXATTR);
+}
+
+int ll_removexattr(struct dentry *dentry, const char *name)
+{
+	struct inode *inode = dentry->d_inode;
+
+	LASSERT(inode);
+	LASSERT(name);
+
+	CDEBUG(D_VFSTRACE, "VFS Op:inode=%lu/%u(%p), xattr %s\n",
+	       inode->i_ino, inode->i_generation, inode, name);
+
+	ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_REMOVEXATTR, 1);
+	return ll_setxattr_common(inode, name, NULL, 0, 0,
+				  OBD_MD_FLXATTRRM);
+}
+
+static
+int ll_getxattr_common(struct inode *inode, const char *name,
+		       void *buffer, size_t size, __u64 valid)
+{
+	struct ll_sb_info *sbi = ll_i2sbi(inode);
+	struct ptlrpc_request *req = NULL;
+	struct mdt_body *body;
+	int xattr_type, rc;
+	void *xdata;
+	struct obd_capa *oc;
+	struct rmtacl_ctl_entry *rce = NULL;
+	ENTRY;
+
+	CDEBUG(D_VFSTRACE, "VFS Op:inode=%lu/%u(%p)\n",
+	       inode->i_ino, inode->i_generation, inode);
+
+	/* listxattr have slightly different behavior from of ext3:
+	 * without 'user_xattr' ext3 will list all xattr names but
+	 * filtered out "^user..*"; we list them all for simplicity.
+	 */
+	if (!name) {
+		xattr_type = XATTR_OTHER_T;
+		goto do_getxattr;
+	}
+
+	xattr_type = get_xattr_type(name);
+	rc = xattr_type_filter(sbi, xattr_type);
+	if (rc)
+		RETURN(rc);
+
+	/* b15587: ignore security.capability xattr for now */
+	if ((xattr_type == XATTR_SECURITY_T &&
+	    strcmp(name, "security.capability") == 0))
+		RETURN(-ENODATA);
+
+	/* LU-549:  Disable security.selinux when selinux is disabled */
+	if (xattr_type == XATTR_SECURITY_T && !selinux_is_enabled() &&
+	    strcmp(name, "security.selinux") == 0)
+		RETURN(-EOPNOTSUPP);
+
+#ifdef CONFIG_FS_POSIX_ACL
+	if (sbi->ll_flags & LL_SBI_RMT_CLIENT &&
+	    (xattr_type == XATTR_ACL_ACCESS_T ||
+	    xattr_type == XATTR_ACL_DEFAULT_T)) {
+		rce = rct_search(&sbi->ll_rct, current_pid());
+		if (rce == NULL ||
+		    (rce->rce_ops != RMT_LSETFACL &&
+		    rce->rce_ops != RMT_LGETFACL &&
+		    rce->rce_ops != RMT_RSETFACL &&
+		    rce->rce_ops != RMT_RGETFACL))
+			RETURN(-EOPNOTSUPP);
+	}
+
+	/* posix acl is under protection of LOOKUP lock. when calling to this,
+	 * we just have path resolution to the target inode, so we have great
+	 * chance that cached ACL is uptodate.
+	 */
+	if (xattr_type == XATTR_ACL_ACCESS_T &&
+	    !(sbi->ll_flags & LL_SBI_RMT_CLIENT)) {
+		struct ll_inode_info *lli = ll_i2info(inode);
+		struct posix_acl *acl;
+
+		spin_lock(&lli->lli_lock);
+		acl = posix_acl_dup(lli->lli_posix_acl);
+		spin_unlock(&lli->lli_lock);
+
+		if (!acl)
+			RETURN(-ENODATA);
+
+		rc = posix_acl_to_xattr(&init_user_ns, acl, buffer, size);
+		posix_acl_release(acl);
+		RETURN(rc);
+	}
+	if (xattr_type == XATTR_ACL_DEFAULT_T && !S_ISDIR(inode->i_mode))
+		RETURN(-ENODATA);
+#endif
+
+do_getxattr:
+	oc = ll_mdscapa_get(inode);
+	rc = md_getxattr(sbi->ll_md_exp, ll_inode2fid(inode), oc,
+			 valid | (rce ? rce_ops2valid(rce->rce_ops) : 0),
+			 name, NULL, 0, size, 0, &req);
+	capa_put(oc);
+	if (rc) {
+		if (rc == -EOPNOTSUPP && xattr_type == XATTR_USER_T) {
+			LCONSOLE_INFO("Disabling user_xattr feature because "
+				      "it is not supported on the server\n");
+			sbi->ll_flags &= ~LL_SBI_USER_XATTR;
+		}
+		RETURN(rc);
+	}
+
+	body = req_capsule_server_get(&req->rq_pill, &RMF_MDT_BODY);
+	LASSERT(body);
+
+	/* only detect the xattr size */
+	if (size == 0)
+		GOTO(out, rc = body->eadatasize);
+
+	if (size < body->eadatasize) {
+		CERROR("server bug: replied size %u > %u\n",
+		       body->eadatasize, (int)size);
+		GOTO(out, rc = -ERANGE);
+	}
+
+	if (body->eadatasize == 0)
+		GOTO(out, rc = -ENODATA);
+
+	/* do not need swab xattr data */
+	xdata = req_capsule_server_sized_get(&req->rq_pill, &RMF_EADATA,
+					     body->eadatasize);
+	if (!xdata)
+		GOTO(out, rc = -EFAULT);
+
+#ifdef CONFIG_FS_POSIX_ACL
+	if (body->eadatasize >= 0 && rce && rce->rce_ops == RMT_LSETFACL) {
+		ext_acl_xattr_header *acl;
+
+		acl = lustre_posix_acl_xattr_2ext((posix_acl_xattr_header *)xdata,
+						  body->eadatasize);
+		if (IS_ERR(acl))
+			GOTO(out, rc = PTR_ERR(acl));
+
+		rc = ee_add(&sbi->ll_et, current_pid(), ll_inode2fid(inode),
+			    xattr_type, acl);
+		if (unlikely(rc < 0)) {
+			lustre_ext_acl_xattr_free(acl);
+			GOTO(out, rc);
+		}
+	}
+#endif
+
+	if (body->eadatasize == 0) {
+		rc = -ENODATA;
+	} else {
+		LASSERT(buffer);
+		memcpy(buffer, xdata, body->eadatasize);
+		rc = body->eadatasize;
+	}
+	EXIT;
+out:
+	ptlrpc_req_finished(req);
+	return rc;
+}
+
+ssize_t ll_getxattr(struct dentry *dentry, const char *name,
+		    void *buffer, size_t size)
+{
+	struct inode *inode = dentry->d_inode;
+
+	LASSERT(inode);
+	LASSERT(name);
+
+	CDEBUG(D_VFSTRACE, "VFS Op:inode=%lu/%u(%p), xattr %s\n",
+	       inode->i_ino, inode->i_generation, inode, name);
+
+	ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_GETXATTR, 1);
+
+	if ((strncmp(name, XATTR_TRUSTED_PREFIX,
+		     sizeof(XATTR_TRUSTED_PREFIX) - 1) == 0 &&
+	     strcmp(name + sizeof(XATTR_TRUSTED_PREFIX) - 1, "lov") == 0) ||
+	    (strncmp(name, XATTR_LUSTRE_PREFIX,
+		     sizeof(XATTR_LUSTRE_PREFIX) - 1) == 0 &&
+	     strcmp(name + sizeof(XATTR_LUSTRE_PREFIX) - 1, "lov") == 0)) {
+		struct lov_stripe_md *lsm;
+		struct lov_user_md *lump;
+		struct lov_mds_md *lmm = NULL;
+		struct ptlrpc_request *request = NULL;
+		int rc = 0, lmmsize = 0;
+
+		if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode))
+			return -ENODATA;
+
+		if (size == 0 && S_ISDIR(inode->i_mode)) {
+			/* XXX directory EA is fix for now, optimize to save
+			 * RPC transfer */
+			GOTO(out, rc = sizeof(struct lov_user_md));
+		}
+
+		lsm = ccc_inode_lsm_get(inode);
+		if (lsm == NULL) {
+			if (S_ISDIR(inode->i_mode)) {
+				rc = ll_dir_getstripe(inode, &lmm,
+						      &lmmsize, &request);
+			} else {
+				rc = -ENODATA;
+			}
+		} else {
+			/* LSM is present already after lookup/getattr call.
+			 * we need to grab layout lock once it is implemented */
+			rc = obd_packmd(ll_i2dtexp(inode), &lmm, lsm);
+			lmmsize = rc;
+		}
+		ccc_inode_lsm_put(inode, lsm);
+
+		if (rc < 0)
+		       GOTO(out, rc);
+
+		if (size == 0) {
+			/* used to call ll_get_max_mdsize() forward to get
+			 * the maximum buffer size, while some apps (such as
+			 * rsync 3.0.x) care much about the exact xattr value
+			 * size */
+			rc = lmmsize;
+			GOTO(out, rc);
+		}
+
+		if (size < lmmsize) {
+			CERROR("server bug: replied size %d > %d for %s (%s)\n",
+			       lmmsize, (int)size, dentry->d_name.name, name);
+			GOTO(out, rc = -ERANGE);
+		}
+
+		lump = (struct lov_user_md *)buffer;
+		memcpy(lump, lmm, lmmsize);
+		/* do not return layout gen for getxattr otherwise it would
+		 * confuse tar --xattr by recognizing layout gen as stripe
+		 * offset when the file is restored. See LU-2809. */
+		lump->lmm_layout_gen = 0;
+
+		rc = lmmsize;
+out:
+		if (request)
+			ptlrpc_req_finished(request);
+		else if (lmm)
+			obd_free_diskmd(ll_i2dtexp(inode), &lmm);
+		return(rc);
+	}
+
+	return ll_getxattr_common(inode, name, buffer, size, OBD_MD_FLXATTR);
+}
+
+ssize_t ll_listxattr(struct dentry *dentry, char *buffer, size_t size)
+{
+	struct inode *inode = dentry->d_inode;
+	int rc = 0, rc2 = 0;
+	struct lov_mds_md *lmm = NULL;
+	struct ptlrpc_request *request = NULL;
+	int lmmsize;
+
+	LASSERT(inode);
+
+	CDEBUG(D_VFSTRACE, "VFS Op:inode=%lu/%u(%p)\n",
+	       inode->i_ino, inode->i_generation, inode);
+
+	ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_LISTXATTR, 1);
+
+	rc = ll_getxattr_common(inode, NULL, buffer, size, OBD_MD_FLXATTRLS);
+	if (rc < 0)
+		GOTO(out, rc);
+
+	if (buffer != NULL) {
+		struct ll_sb_info *sbi = ll_i2sbi(inode);
+		char *xattr_name = buffer;
+		int xlen, rem = rc;
+
+		while (rem > 0) {
+			xlen = strnlen(xattr_name, rem - 1) + 1;
+			rem -= xlen;
+			if (xattr_type_filter(sbi,
+					get_xattr_type(xattr_name)) == 0) {
+				/* skip OK xattr type
+				 * leave it in buffer
+				 */
+				xattr_name += xlen;
+				continue;
+			}
+			/* move up remaining xattrs in buffer
+			 * removing the xattr that is not OK
+			 */
+			memmove(xattr_name, xattr_name + xlen, rem);
+			rc -= xlen;
+		}
+	}
+	if (S_ISREG(inode->i_mode)) {
+		if (!ll_i2info(inode)->lli_has_smd)
+			rc2 = -1;
+	} else if (S_ISDIR(inode->i_mode)) {
+		rc2 = ll_dir_getstripe(inode, &lmm, &lmmsize, &request);
+	}
+
+	if (rc2 < 0) {
+		GOTO(out, rc2 = 0);
+	} else if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)) {
+		const int prefix_len = sizeof(XATTR_LUSTRE_PREFIX) - 1;
+		const size_t name_len   = sizeof("lov") - 1;
+		const size_t total_len  = prefix_len + name_len + 1;
+
+		if (buffer && (rc + total_len) <= size) {
+			buffer += rc;
+			memcpy(buffer, XATTR_LUSTRE_PREFIX, prefix_len);
+			memcpy(buffer + prefix_len, "lov", name_len);
+			buffer[prefix_len + name_len] = '\0';
+		}
+		rc2 = total_len;
+	}
+out:
+	ptlrpc_req_finished(request);
+	rc = rc + rc2;
+
+	return rc;
+}