[RFC PATCH 04/13] xfs: add parent pointer support to attribute code

Allison Henderson
2017-08-10T01:43:50Z

From: Mark Tinguely <tinguely@sgi.com>

Add the new parent attribute type. XFS_ATTR_PARENT is used only for
parent pointer entries; it uses reserved blocks like XFS_ATTR_ROOT.

[dchinner: forward ported and cleaned up]
[achender: rebased]

Signed-off-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
---
:100644 100644 de7b9bd... 646d41b... M fs/xfs/libxfs/xfs_attr.c
:100644 100644 3771edc... 5f94c84... M fs/xfs/libxfs/xfs_da_format.h
:100644 100644 5d5a5e2... 3031a09... M fs/xfs/xfs_attr.h
fs/xfs/libxfs/xfs_attr.c | 9 +++++----
fs/xfs/libxfs/xfs_da_format.h | 12 ++++++++----
fs/xfs/xfs_attr.h | 2 ++
3 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
index de7b9bd..646d41b 100644
--- a/fs/xfs/libxfs/xfs_attr.c
+++ b/fs/xfs/libxfs/xfs_attr.c
@@ -216,7 +216,7 @@ xfs_attr_set(
struct xfs_defer_ops dfops;
struct xfs_trans_res tres;
xfs_fsblock_t firstblock;
- int rsvd = (flags & ATTR_ROOT) != 0;
+ bool rsvd = (flags & (ATTR_ROOT | ATTR_PARENT)) != 0;
int error, err2, local;

XFS_STATS_INC(mp, xs_attr_set);
@@ -395,6 +395,7 @@ xfs_attr_remove(
struct xfs_defer_ops dfops;
xfs_fsblock_t firstblock;
int error;
+ int rsvd = 0;

XFS_STATS_INC(mp, xs_attr_remove);

@@ -423,10 +424,10 @@ xfs_attr_remove(
* Root fork attributes can use reserved data blocks for this
* operation if necessary
*/
+ if (flags & (ATTR_ROOT | ATTR_PARENT))
+ rsvd = XFS_TRANS_RESERVE;
error = xfs_trans_alloc(mp, &M_RES(mp)->tr_attrrm,
- XFS_ATTRRM_SPACE_RES(mp), 0,
- (flags & ATTR_ROOT) ? XFS_TRANS_RESERVE : 0,
- &args.trans);
+ XFS_ATTRRM_SPACE_RES(mp), 0, rsvd, &args.trans);
if (error)
return error;

diff --git a/fs/xfs/libxfs/xfs_da_format.h b/fs/xfs/libxfs/xfs_da_format.h
index 3771edc..5f94c84 100644
--- a/fs/xfs/libxfs/xfs_da_format.h
+++ b/fs/xfs/libxfs/xfs_da_format.h
@@ -758,24 +758,28 @@ struct xfs_attr3_icleaf_hdr {
#define XFS_ATTR_LOCAL_BIT 0 /* attr is stored locally */
#define XFS_ATTR_ROOT_BIT 1 /* limit access to trusted attrs */
#define XFS_ATTR_SECURE_BIT 2 /* limit access to secure attrs */
+#define XFS_ATTR_PARENT_BIT 3 /* parent pointer secure attrs */
#define XFS_ATTR_INCOMPLETE_BIT 7 /* attr in middle of create/delete */
#define XFS_ATTR_LOCAL (1 << XFS_ATTR_LOCAL_BIT)
#define XFS_ATTR_ROOT (1 << XFS_ATTR_ROOT_BIT)
#define XFS_ATTR_SECURE (1 << XFS_ATTR_SECURE_BIT)
+#define XFS_ATTR_PARENT (1 << XFS_ATTR_PARENT_BIT)
#define XFS_ATTR_INCOMPLETE (1 << XFS_ATTR_INCOMPLETE_BIT)

/*
* Conversion macros for converting namespace bits from argument flags
* to ondisk flags.
*/
-#define XFS_ATTR_NSP_ARGS_MASK (ATTR_ROOT | ATTR_SECURE)
-#define XFS_ATTR_NSP_ONDISK_MASK (XFS_ATTR_ROOT | XFS_ATTR_SECURE)
+#define XFS_ATTR_NSP_ARGS_MASK (ATTR_ROOT | ATTR_SECURE | XFS_ATTR_PARENT)
+#define XFS_ATTR_NSP_ONDISK_MASK (XFS_ATTR_ROOT | XFS_ATTR_SECURE | XFS_ATTR_PARENT)
#define XFS_ATTR_NSP_ONDISK(flags) ((flags) & XFS_ATTR_NSP_ONDISK_MASK)
#define XFS_ATTR_NSP_ARGS(flags) ((flags) & XFS_ATTR_NSP_ARGS_MASK)
#define XFS_ATTR_NSP_ARGS_TO_ONDISK(x) (((x) & ATTR_ROOT ? XFS_ATTR_ROOT : 0) |\
- ((x) & ATTR_SECURE ? XFS_ATTR_SECURE : 0))
+ ((x) & ATTR_SECURE ? XFS_ATTR_SECURE : 0) | \
+ ((x) & ATTR_PARENT ? XFS_ATTR_PARENT : 0))
#define XFS_ATTR_NSP_ONDISK_TO_ARGS(x) (((x) & XFS_ATTR_ROOT ? ATTR_ROOT : 0) |\
- ((x) & XFS_ATTR_SECURE ? ATTR_SECURE : 0))
+ ((x) & XFS_ATTR_SECURE ? ATTR_SECURE : 0) | \
+ ((x) & XFS_ATTR_PARENT ? ATTR_PARENT : 0))

/*
* Alignment for namelist and valuelist entries (since they are mixed
diff --git a/fs/xfs/xfs_attr.h b/fs/xfs/xfs_attr.h
index 5d5a5e2..3031a09 100644
--- a/fs/xfs/xfs_attr.h
+++ b/fs/xfs/xfs_attr.h
@@ -44,6 +44,7 @@ struct xfs_attr_list_context;
#define ATTR_SECURE 0x0008 /* use attrs in security namespace */
#define ATTR_CREATE 0x0010 /* pure create: fail if attr already exists */
#define ATTR_REPLACE 0x0020 /* pure set: fail if attr does not exist */
+#define ATTR_PARENT 0x0040 /* use attrs in parent namespace */

#define ATTR_KERNOTIME 0x1000 /* [kernel] don't update inode timestamps */
#define ATTR_KERNOVAL 0x2000 /* [kernel] get attr size only, not value */
@@ -55,6 +56,7 @@ struct xfs_attr_list_context;
{ ATTR_SECURE, "SECURE" }, \
{ ATTR_CREATE, "CREATE" }, \
{ ATTR_REPLACE, "REPLACE" }, \
+ { ATTR_PARENT, "PARENT" }, \
{ ATTR_KERNOTIME, "KERNOTIME" }, \
{ ATTR_KERNOVAL, "KERNOVAL" }

--
2.7.4