Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
[pandora-kernel.git] / fs / xfs / xfs_alloc.c
index f322798..27d64d7 100644 (file)
@@ -147,10 +147,9 @@ xfs_alloc_get_rec(
  */
 STATIC void
 xfs_alloc_compute_aligned(
+       xfs_alloc_arg_t *args,          /* allocation argument structure */
        xfs_agblock_t   foundbno,       /* starting block in found extent */
        xfs_extlen_t    foundlen,       /* length in found extent */
-       xfs_extlen_t    alignment,      /* alignment for allocation */
-       xfs_extlen_t    minlen,         /* minimum length for allocation */
        xfs_agblock_t   *resbno,        /* result block number */
        xfs_extlen_t    *reslen)        /* result length */
 {
@@ -158,8 +157,8 @@ xfs_alloc_compute_aligned(
        xfs_extlen_t    diff;
        xfs_extlen_t    len;
 
-       if (alignment > 1 && foundlen >= minlen) {
-               bno = roundup(foundbno, alignment);
+       if (args->alignment > 1 && foundlen >= args->minlen) {
+               bno = roundup(foundbno, args->alignment);
                diff = bno - foundbno;
                len = diff >= foundlen ? 0 : foundlen - diff;
        } else {
@@ -464,6 +463,27 @@ xfs_alloc_read_agfl(
        return 0;
 }
 
+STATIC int
+xfs_alloc_update_counters(
+       struct xfs_trans        *tp,
+       struct xfs_perag        *pag,
+       struct xfs_buf          *agbp,
+       long                    len)
+{
+       struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
+
+       pag->pagf_freeblks += len;
+       be32_add_cpu(&agf->agf_freeblks, len);
+
+       xfs_trans_agblocks_delta(tp, len);
+       if (unlikely(be32_to_cpu(agf->agf_freeblks) >
+                    be32_to_cpu(agf->agf_length)))
+               return EFSCORRUPTED;
+
+       xfs_alloc_log_agf(tp, agbp, XFS_AGF_FREEBLKS);
+       return 0;
+}
+
 /*
  * Allocation group level functions.
  */
@@ -505,49 +525,44 @@ xfs_alloc_ag_vextent(
                ASSERT(0);
                /* NOTREACHED */
        }
-       if (error)
+
+       if (error || args->agbno == NULLAGBLOCK)
                return error;
-       /*
-        * If the allocation worked, need to change the agf structure
-        * (and log it), and the superblock.
-        */
-       if (args->agbno != NULLAGBLOCK) {
-               xfs_agf_t       *agf;   /* allocation group freelist header */
-               long            slen = (long)args->len;
 
-               ASSERT(args->len >= args->minlen && args->len <= args->maxlen);
-               ASSERT(!(args->wasfromfl) || !args->isfl);
-               ASSERT(args->agbno % args->alignment == 0);
-               if (!(args->wasfromfl)) {
-
-                       agf = XFS_BUF_TO_AGF(args->agbp);
-                       be32_add_cpu(&agf->agf_freeblks, -(args->len));
-                       xfs_trans_agblocks_delta(args->tp,
-                                                -((long)(args->len)));
-                       args->pag->pagf_freeblks -= args->len;
-                       ASSERT(be32_to_cpu(agf->agf_freeblks) <=
-                               be32_to_cpu(agf->agf_length));
-                       xfs_alloc_log_agf(args->tp, args->agbp,
-                                               XFS_AGF_FREEBLKS);
-                       /*
-                        * Search the busylist for these blocks and mark the
-                        * transaction as synchronous if blocks are found. This
-                        * avoids the need to block due to a synchronous log
-                        * force to ensure correct ordering as the synchronous
-                        * transaction will guarantee that for us.
-                        */
-                       if (xfs_alloc_busy_search(args->mp, args->agno,
-                                               args->agbno, args->len))
-                               xfs_trans_set_sync(args->tp);
-               }
-               if (!args->isfl)
-                       xfs_trans_mod_sb(args->tp,
-                               args->wasdel ? XFS_TRANS_SB_RES_FDBLOCKS :
-                                       XFS_TRANS_SB_FDBLOCKS, -slen);
-               XFS_STATS_INC(xs_allocx);
-               XFS_STATS_ADD(xs_allocb, args->len);
+       ASSERT(args->len >= args->minlen);
+       ASSERT(args->len <= args->maxlen);
+       ASSERT(!args->wasfromfl || !args->isfl);
+       ASSERT(args->agbno % args->alignment == 0);
+
+       if (!args->wasfromfl) {
+               error = xfs_alloc_update_counters(args->tp, args->pag,
+                                                 args->agbp,
+                                                 -((long)(args->len)));
+               if (error)
+                       return error;
+
+               /*
+                * Search the busylist for these blocks and mark the
+                * transaction as synchronous if blocks are found. This
+                * avoids the need to block due to a synchronous log
+                * force to ensure correct ordering as the synchronous
+                * transaction will guarantee that for us.
+                */
+               if (xfs_alloc_busy_search(args->mp, args->agno,
+                                       args->agbno, args->len))
+                       xfs_trans_set_sync(args->tp);
        }
-       return 0;
+
+       if (!args->isfl) {
+               xfs_trans_mod_sb(args->tp, args->wasdel ?
+                                XFS_TRANS_SB_RES_FDBLOCKS :
+                                XFS_TRANS_SB_FDBLOCKS,
+                                -((long)(args->len)));
+       }
+
+       XFS_STATS_INC(xs_allocx);
+       XFS_STATS_ADD(xs_allocb, args->len);
+       return error;
 }
 
 /*
@@ -693,8 +708,7 @@ xfs_alloc_find_best_extent(
                if (error)
                        goto error0;
                XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
-               xfs_alloc_compute_aligned(*sbno, *slen, args->alignment,
-                                         args->minlen, &bno, slena);
+               xfs_alloc_compute_aligned(args, *sbno, *slen, &bno, slena);
 
                /*
                 * The good extent is closer than this one.
@@ -866,8 +880,8 @@ xfs_alloc_ag_vextent_near(
                        if ((error = xfs_alloc_get_rec(cnt_cur, &ltbno, &ltlen, &i)))
                                goto error0;
                        XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
-                       xfs_alloc_compute_aligned(ltbno, ltlen, args->alignment,
-                                       args->minlen, &ltbnoa, &ltlena);
+                       xfs_alloc_compute_aligned(args, ltbno, ltlen,
+                                                 &ltbnoa, &ltlena);
                        if (ltlena < args->minlen)
                                continue;
                        args->len = XFS_EXTLEN_MIN(ltlena, args->maxlen);
@@ -987,8 +1001,8 @@ xfs_alloc_ag_vextent_near(
                        if ((error = xfs_alloc_get_rec(bno_cur_lt, &ltbno, &ltlen, &i)))
                                goto error0;
                        XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
-                       xfs_alloc_compute_aligned(ltbno, ltlen, args->alignment,
-                                       args->minlen, &ltbnoa, &ltlena);
+                       xfs_alloc_compute_aligned(args, ltbno, ltlen,
+                                                 &ltbnoa, &ltlena);
                        if (ltlena >= args->minlen)
                                break;
                        if ((error = xfs_btree_decrement(bno_cur_lt, 0, &i)))
@@ -1003,8 +1017,8 @@ xfs_alloc_ag_vextent_near(
                        if ((error = xfs_alloc_get_rec(bno_cur_gt, &gtbno, &gtlen, &i)))
                                goto error0;
                        XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
-                       xfs_alloc_compute_aligned(gtbno, gtlen, args->alignment,
-                                       args->minlen, &gtbnoa, &gtlena);
+                       xfs_alloc_compute_aligned(args, gtbno, gtlen,
+                                                 &gtbnoa, &gtlena);
                        if (gtlena >= args->minlen)
                                break;
                        if ((error = xfs_btree_increment(bno_cur_gt, 0, &i)))
@@ -1183,8 +1197,7 @@ xfs_alloc_ag_vextent_size(
         * once aligned; if not, we search left for something better.
         * This can't happen in the second case above.
         */
-       xfs_alloc_compute_aligned(fbno, flen, args->alignment, args->minlen,
-               &rbno, &rlen);
+       xfs_alloc_compute_aligned(args, fbno, flen, &rbno, &rlen);
        rlen = XFS_EXTLEN_MIN(args->maxlen, rlen);
        XFS_WANT_CORRUPTED_GOTO(rlen == 0 ||
                        (rlen <= flen && rbno + rlen <= fbno + flen), error0);
@@ -1209,8 +1222,8 @@ xfs_alloc_ag_vextent_size(
                        XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
                        if (flen < bestrlen)
                                break;
-                       xfs_alloc_compute_aligned(fbno, flen, args->alignment,
-                               args->minlen, &rbno, &rlen);
+                       xfs_alloc_compute_aligned(args, fbno, flen,
+                                                 &rbno, &rlen);
                        rlen = XFS_EXTLEN_MIN(args->maxlen, rlen);
                        XFS_WANT_CORRUPTED_GOTO(rlen == 0 ||
                                (rlen <= flen && rbno + rlen <= fbno + flen),
@@ -1388,6 +1401,7 @@ xfs_free_ag_extent(
        xfs_mount_t     *mp;            /* mount point struct for filesystem */
        xfs_agblock_t   nbno;           /* new starting block of freespace */
        xfs_extlen_t    nlen;           /* new length of freespace */
+       xfs_perag_t     *pag;           /* per allocation group data */
 
        mp = tp->t_mountp;
        /*
@@ -1586,30 +1600,20 @@ xfs_free_ag_extent(
        XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
        xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
        cnt_cur = NULL;
+
        /*
         * Update the freespace totals in the ag and superblock.
         */
-       {
-               xfs_agf_t       *agf;
-               xfs_perag_t     *pag;           /* per allocation group data */
-
-               pag = xfs_perag_get(mp, agno);
-               pag->pagf_freeblks += len;
-               xfs_perag_put(pag);
-
-               agf = XFS_BUF_TO_AGF(agbp);
-               be32_add_cpu(&agf->agf_freeblks, len);
-               xfs_trans_agblocks_delta(tp, len);
-               XFS_WANT_CORRUPTED_GOTO(
-                       be32_to_cpu(agf->agf_freeblks) <=
-                       be32_to_cpu(agf->agf_length),
-                       error0);
-               xfs_alloc_log_agf(tp, agbp, XFS_AGF_FREEBLKS);
-               if (!isfl)
-                       xfs_trans_mod_sb(tp, XFS_TRANS_SB_FDBLOCKS, (long)len);
-               XFS_STATS_INC(xs_freex);
-               XFS_STATS_ADD(xs_freeb, len);
-       }
+       pag = xfs_perag_get(mp, agno);
+       error = xfs_alloc_update_counters(tp, pag, agbp, len);
+       xfs_perag_put(pag);
+       if (error)
+               goto error0;
+
+       if (!isfl)
+               xfs_trans_mod_sb(tp, XFS_TRANS_SB_FDBLOCKS, (long)len);
+       XFS_STATS_INC(xs_freex);
+       XFS_STATS_ADD(xs_freeb, len);
 
        trace_xfs_free_extent(mp, agno, bno, len, isfl, haveleft, haveright);
 
@@ -2391,17 +2395,33 @@ xfs_free_extent(
        memset(&args, 0, sizeof(xfs_alloc_arg_t));
        args.tp = tp;
        args.mp = tp->t_mountp;
+
+       /*
+        * validate that the block number is legal - the enables us to detect
+        * and handle a silent filesystem corruption rather than crashing.
+        */
        args.agno = XFS_FSB_TO_AGNO(args.mp, bno);
-       ASSERT(args.agno < args.mp->m_sb.sb_agcount);
+       if (args.agno >= args.mp->m_sb.sb_agcount)
+               return EFSCORRUPTED;
+
        args.agbno = XFS_FSB_TO_AGBNO(args.mp, bno);
+       if (args.agbno >= args.mp->m_sb.sb_agblocks)
+               return EFSCORRUPTED;
+
        args.pag = xfs_perag_get(args.mp, args.agno);
-       if ((error = xfs_alloc_fix_freelist(&args, XFS_ALLOC_FLAG_FREEING)))
+       ASSERT(args.pag);
+
+       error = xfs_alloc_fix_freelist(&args, XFS_ALLOC_FLAG_FREEING);
+       if (error)
                goto error0;
-#ifdef DEBUG
-       ASSERT(args.agbp != NULL);
-       ASSERT((args.agbno + len) <=
-               be32_to_cpu(XFS_BUF_TO_AGF(args.agbp)->agf_length));
-#endif
+
+       /* validate the extent size is legal now we have the agf locked */
+       if (args.agbno + len >
+                       be32_to_cpu(XFS_BUF_TO_AGF(args.agbp)->agf_length)) {
+               error = EFSCORRUPTED;
+               goto error0;
+       }
+
        error = xfs_free_ag_extent(tp, args.agbp, args.agno, args.agbno, len, 0);
 error0:
        xfs_perag_put(args.pag);