xfs: Enable bulkstat ioctl to support 64-bit per-inode extent counters

The following changes are made to enable userspace to obtain 64-bit extent
counters,
1. Carve out a new 64-bit field xfs_bulkstat->bs_extents64 from
   xfs_bulkstat->bs_pad[] to hold 64-bit extent counter.
2. Define the new flag XFS_BULK_IREQ_BULKSTAT for userspace to indicate that
   it is capable of receiving 64-bit extent counters.

Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Suggested-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandan.babu@oracle.com>

diff --git a/fs/xfs/libxfs/xfs_fs.h b/fs/xfs/libxfs/xfs_fs.h
index 1f7238d..1d2682c 100644 (file)
--- a/fs/xfs/libxfs/xfs_fs.h
+++ b/fs/xfs/libxfs/xfs_fs.h
@@ -378,7 +378,7 @@ struct xfs_bulkstat {
        uint32_t        bs_extsize_blks; /* extent size hint, blocks    */
 
        uint32_t        bs_nlink;       /* number of links              */
-       uint32_t        bs_extents;     /* number of extents            */
+       uint32_t        bs_extents;     /* 32-bit data fork extent counter */
        uint32_t        bs_aextents;    /* attribute number of extents  */
        uint16_t        bs_version;     /* structure version            */
        uint16_t        bs_forkoff;     /* inode fork offset in bytes   */
@@ -387,8 +387,9 @@ struct xfs_bulkstat {
        uint16_t        bs_checked;     /* checked inode metadata       */
        uint16_t        bs_mode;        /* type and mode                */
        uint16_t        bs_pad2;        /* zeroed                       */
+       uint64_t        bs_extents64;   /* 64-bit data fork extent counter */
 
-       uint64_t        bs_pad[7];      /* zeroed                       */
+       uint64_t        bs_pad[6];      /* zeroed                       */
 };
 
 #define XFS_BULKSTAT_VERSION_V1        (1)
@@ -460,17 +461,28 @@ struct xfs_bulk_ireq {
  * Only return results from the specified @agno.  If @ino is zero, start
  * with the first inode of @agno.
  */
-#define XFS_BULK_IREQ_AGNO     (1 << 0)
+#define XFS_BULK_IREQ_AGNO     (1U << 0)
 
 /*
  * Return bulkstat information for a single inode, where @ino value is a
  * special value, not a literal inode number.  See the XFS_BULK_IREQ_SPECIAL_*
  * values below.  Not compatible with XFS_BULK_IREQ_AGNO.
  */
-#define XFS_BULK_IREQ_SPECIAL  (1 << 1)
+#define XFS_BULK_IREQ_SPECIAL  (1U << 1)
 
-#define XFS_BULK_IREQ_FLAGS_ALL        (XFS_BULK_IREQ_AGNO | \
-                                XFS_BULK_IREQ_SPECIAL)
+/*
+ * Return data fork extent count via xfs_bulkstat->bs_extents64 field and assign
+ * 0 to xfs_bulkstat->bs_extents when the flag is set.  Otherwise, use
+ * xfs_bulkstat->bs_extents for returning data fork extent count and set
+ * xfs_bulkstat->bs_extents64 to 0. In the second case, return -EOVERFLOW and
+ * assign 0 to xfs_bulkstat->bs_extents if data fork extent count is larger than
+ * XFS_MAX_EXTCNT_DATA_FORK_OLD.
+ */
+#define XFS_BULK_IREQ_NREXT64  (1U << 2)
+
+#define XFS_BULK_IREQ_FLAGS_ALL        (XFS_BULK_IREQ_AGNO |    \
+                                XFS_BULK_IREQ_SPECIAL | \
+                                XFS_BULK_IREQ_NREXT64)
 
 /* Operate on the root directory inode. */
 #define XFS_BULK_IREQ_SPECIAL_ROOT     (1)

diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 8348100..e9eadc7 100644 (file)
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -813,6 +813,9 @@ xfs_bulk_ireq_setup(
        if (XFS_INO_TO_AGNO(mp, breq->startino) >= mp->m_sb.sb_agcount)
                return -ECANCELED;
 
+       if (hdr->flags & XFS_BULK_IREQ_NREXT64)
+               breq->flags |= XFS_IBULK_NREXT64;
+
        return 0;
 }
 

diff --git a/fs/xfs/xfs_itable.c b/fs/xfs/xfs_itable.c
index 71ed490..f74c9ff 100644 (file)
--- a/fs/xfs/xfs_itable.c
+++ b/fs/xfs/xfs_itable.c
@@ -64,6 +64,7 @@ xfs_bulkstat_one_int(
        struct xfs_inode        *ip;            /* incore inode pointer */
        struct inode            *inode;
        struct xfs_bulkstat     *buf = bc->buf;
+       xfs_extnum_t            nextents;
        int                     error = -EINVAL;
 
        if (xfs_internal_inum(mp, ino))
@@ -102,7 +103,13 @@ xfs_bulkstat_one_int(
 
        buf->bs_xflags = xfs_ip2xflags(ip);
        buf->bs_extsize_blks = ip->i_extsize;
-       buf->bs_extents = xfs_ifork_nextents(&ip->i_df);
+
+       nextents = xfs_ifork_nextents(&ip->i_df);
+       if (!(bc->breq->flags & XFS_IBULK_NREXT64))
+               buf->bs_extents = min(nextents, XFS_MAX_EXTCNT_DATA_FORK_SMALL);
+       else
+               buf->bs_extents64 = nextents;
+
        xfs_bulkstat_health(ip, buf);
        buf->bs_aextents = xfs_ifork_nextents(ip->i_afp);
        buf->bs_forkoff = XFS_IFORK_BOFF(ip);

diff --git a/fs/xfs/xfs_itable.h b/fs/xfs/xfs_itable.h
index 5ee1d3f..e2d0eba 100644 (file)
--- a/fs/xfs/xfs_itable.h
+++ b/fs/xfs/xfs_itable.h
@@ -19,6 +19,9 @@ struct xfs_ibulk {
 /* Only iterate within the same AG as startino */
 #define XFS_IBULK_SAME_AG      (1U << 0)
 
+/* Fill out the bs_extents64 field if set. */
+#define XFS_IBULK_NREXT64      (1U << 1)
+
 /*
  * Advance the user buffer pointer by one record of the given size.  If the
  * buffer is now full, return the appropriate error code.