xfs: add CRC checks to the AGI
authorDave Chinner <dgc@sgi.com>
Wed, 3 Apr 2013 05:11:15 +0000 (16:11 +1100)
committerBen Myers <bpm@sgi.com>
Sun, 21 Apr 2013 19:57:43 +0000 (14:57 -0500)
Same set of changes made to the AGF need to be made to the AGI.
This patch has a similar history to the AGF, hence a similar
sign-off chain.

Signed-off-by: Dave Chinner <dgc@sgi.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dgc@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
fs/xfs/xfs_ag.h
fs/xfs/xfs_buf_item.h
fs/xfs/xfs_fsops.c
fs/xfs/xfs_ialloc.c
fs/xfs/xfs_log_recover.c

index 272ef097e2be89612acd78419a19f0a688979c19..317aa86d96ea04925b35e995cc70e1eb024beb28 100644 (file)
@@ -152,6 +152,7 @@ typedef struct xfs_agi {
        __be32          agi_root;       /* root of inode btree */
        __be32          agi_level;      /* levels in inode btree */
        __be32          agi_freecount;  /* number of free inodes */
+
        __be32          agi_newino;     /* new inode just allocated */
        __be32          agi_dirino;     /* last directory inode chunk */
        /*
@@ -159,6 +160,13 @@ typedef struct xfs_agi {
         * still being referenced.
         */
        __be32          agi_unlinked[XFS_AGI_UNLINKED_BUCKETS];
+
+       uuid_t          agi_uuid;       /* uuid of filesystem */
+       __be32          agi_crc;        /* crc of agi sector */
+       __be32          agi_pad32;
+       __be64          agi_lsn;        /* last write sequence */
+
+       /* structure must be padded to 64 bit alignment */
 } xfs_agi_t;
 
 #define        XFS_AGI_MAGICNUM        0x00000001
index 067d5f0fc233612395c3b02e2a5162a84e7d1809..c25660691e08a3f261eb4f143751f41fa9c4a945 100644 (file)
@@ -47,6 +47,7 @@ extern kmem_zone_t    *xfs_buf_item_zone;
 #define XFS_BLF_BTREE_BUF      (1<<5)
 #define XFS_BLF_AGF_BUF                (1<<6)
 #define XFS_BLF_AGFL_BUF       (1<<7)
+#define XFS_BLF_AGI_BUF                (1<<8)
 
 #define XFS_BLF_TYPE_MASK      \
                (XFS_BLF_UDQUOT_BUF | \
@@ -54,7 +55,8 @@ extern kmem_zone_t    *xfs_buf_item_zone;
                 XFS_BLF_GDQUOT_BUF | \
                 XFS_BLF_BTREE_BUF | \
                 XFS_BLF_AGF_BUF | \
-                XFS_BLF_AGFL_BUF)
+                XFS_BLF_AGFL_BUF | \
+                XFS_BLF_AGI_BUF)
 
 #define        XFS_BLF_CHUNK           128
 #define        XFS_BLF_SHIFT           7
index a693a54799e5f39d933f5d39451ad012f55a0b98..87595b211da10743bbd07c7be8b4fd44d9f8212b 100644 (file)
@@ -304,8 +304,11 @@ xfs_growfs_data_private(
                agi->agi_freecount = 0;
                agi->agi_newino = cpu_to_be32(NULLAGINO);
                agi->agi_dirino = cpu_to_be32(NULLAGINO);
+               if (xfs_sb_version_hascrc(&mp->m_sb))
+                       uuid_copy(&agi->agi_uuid, &mp->m_sb.sb_uuid);
                for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++)
                        agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);
+
                error = xfs_bwrite(bp);
                xfs_buf_relse(bp);
                if (error)
index ba626613bf492399bcd64753fbfb4d46e9713aa2..6d0a4954aa8ca9bc0a368c281ccee4c8dcf30589 100644 (file)
@@ -36,6 +36,8 @@
 #include "xfs_rtalloc.h"
 #include "xfs_error.h"
 #include "xfs_bmap.h"
+#include "xfs_cksum.h"
+#include "xfs_buf_item.h"
 
 
 /*
@@ -1453,6 +1455,7 @@ xfs_ialloc_log_agi(
        /*
         * Log the allocation group inode header buffer.
         */
+       xfs_trans_buf_set_type(tp, bp, XFS_BLF_AGI_BUF);
        xfs_trans_log_buf(tp, bp, first, last);
 }
 
@@ -1470,19 +1473,23 @@ xfs_check_agi_unlinked(
 #define xfs_check_agi_unlinked(agi)
 #endif
 
-static void
+static bool
 xfs_agi_verify(
        struct xfs_buf  *bp)
 {
        struct xfs_mount *mp = bp->b_target->bt_mount;
        struct xfs_agi  *agi = XFS_BUF_TO_AGI(bp);
-       int             agi_ok;
 
+       if (xfs_sb_version_hascrc(&mp->m_sb) &&
+           !uuid_equal(&agi->agi_uuid, &mp->m_sb.sb_uuid))
+                       return false;
        /*
         * Validate the magic number of the agi block.
         */
-       agi_ok = agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC) &&
-               XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum));
+       if (agi->agi_magicnum != cpu_to_be32(XFS_AGI_MAGIC))
+               return false;
+       if (!XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)))
+               return false;
 
        /*
         * during growfs operations, the perag is not fully initialised,
@@ -1490,30 +1497,52 @@ xfs_agi_verify(
         * use it by using uncached buffers that don't have the perag attached
         * so we can detect and avoid this problem.
         */
-       if (bp->b_pag)
-               agi_ok = agi_ok && be32_to_cpu(agi->agi_seqno) ==
-                                               bp->b_pag->pag_agno;
+       if (bp->b_pag && be32_to_cpu(agi->agi_seqno) != bp->b_pag->pag_agno)
+               return false;
 
-       if (unlikely(XFS_TEST_ERROR(!agi_ok, mp, XFS_ERRTAG_IALLOC_READ_AGI,
-                       XFS_RANDOM_IALLOC_READ_AGI))) {
-               XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, agi);
-               xfs_buf_ioerror(bp, EFSCORRUPTED);
-       }
        xfs_check_agi_unlinked(agi);
+       return true;
 }
 
 static void
 xfs_agi_read_verify(
        struct xfs_buf  *bp)
 {
-       xfs_agi_verify(bp);
+       struct xfs_mount *mp = bp->b_target->bt_mount;
+       int             agi_ok = 1;
+
+       if (xfs_sb_version_hascrc(&mp->m_sb))
+               agi_ok = xfs_verify_cksum(bp->b_addr, BBTOB(bp->b_length),
+                                         offsetof(struct xfs_agi, agi_crc));
+       agi_ok = agi_ok && xfs_agi_verify(bp);
+
+       if (unlikely(XFS_TEST_ERROR(!agi_ok, mp, XFS_ERRTAG_IALLOC_READ_AGI,
+                       XFS_RANDOM_IALLOC_READ_AGI))) {
+               XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
+               xfs_buf_ioerror(bp, EFSCORRUPTED);
+       }
 }
 
 static void
 xfs_agi_write_verify(
        struct xfs_buf  *bp)
 {
-       xfs_agi_verify(bp);
+       struct xfs_mount *mp = bp->b_target->bt_mount;
+       struct xfs_buf_log_item *bip = bp->b_fspriv;
+
+       if (!xfs_agi_verify(bp)) {
+               XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
+               xfs_buf_ioerror(bp, EFSCORRUPTED);
+               return;
+       }
+
+       if (!xfs_sb_version_hascrc(&mp->m_sb))
+               return;
+
+       if (bip)
+               XFS_BUF_TO_AGI(bp)->agi_lsn = cpu_to_be64(bip->bli_item.li_lsn);
+       xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length),
+                        offsetof(struct xfs_agi, agi_crc));
 }
 
 const struct xfs_buf_ops xfs_agi_buf_ops = {
index da2a19e0554e78dc8150729e49418ffd16c28d83..6778a7943db435386be4c5e23052763c0f1fc7ea 100644 (file)
@@ -1971,6 +1971,14 @@ xlog_recover_do_reg_buffer(
                }
                bp->b_ops = &xfs_agfl_buf_ops;
                break;
+       case XFS_BLF_AGI_BUF:
+               if (*(__be32 *)bp->b_addr != cpu_to_be32(XFS_AGI_MAGIC)) {
+                       xfs_warn(mp, "Bad AGI block magic!");
+                       ASSERT(0);
+                       break;
+               }
+               bp->b_ops = &xfs_agi_buf_ops;
+               break;
        default:
                break;
        }