Merge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6
[safe/jmp/linux-2.6] / fs / ext3 / balloc.c
index f1897fe..27967f9 100644 (file)
@@ -32,7 +32,7 @@
  * The file system contains group descriptors which are located after the
  * super block.  Each descriptor contains the number of the bitmap block and
  * the free blocks count in the block.  The descriptors are loaded in memory
- * when a file system is mounted (see ext3_read_super).
+ * when a file system is mounted (see ext3_fill_super).
  */
 
 
@@ -40,7 +40,7 @@
 
 /**
  * ext3_get_group_desc() -- load group descriptor from disk
- * @sb:                super block
+ * @sb:                        super block
  * @block_group:       given block group
  * @bh:                        pointer to the buffer head to store the block
  *                     group descriptor
@@ -80,13 +80,57 @@ struct ext3_group_desc * ext3_get_group_desc(struct super_block * sb,
        return desc + offset;
 }
 
+static int ext3_valid_block_bitmap(struct super_block *sb,
+                                       struct ext3_group_desc *desc,
+                                       unsigned int block_group,
+                                       struct buffer_head *bh)
+{
+       ext3_grpblk_t offset;
+       ext3_grpblk_t next_zero_bit;
+       ext3_fsblk_t bitmap_blk;
+       ext3_fsblk_t group_first_block;
+
+       group_first_block = ext3_group_first_block_no(sb, block_group);
+
+       /* check whether block bitmap block number is set */
+       bitmap_blk = le32_to_cpu(desc->bg_block_bitmap);
+       offset = bitmap_blk - group_first_block;
+       if (!ext3_test_bit(offset, bh->b_data))
+               /* bad block bitmap */
+               goto err_out;
+
+       /* check whether the inode bitmap block number is set */
+       bitmap_blk = le32_to_cpu(desc->bg_inode_bitmap);
+       offset = bitmap_blk - group_first_block;
+       if (!ext3_test_bit(offset, bh->b_data))
+               /* bad block bitmap */
+               goto err_out;
+
+       /* check whether the inode table block number is set */
+       bitmap_blk = le32_to_cpu(desc->bg_inode_table);
+       offset = bitmap_blk - group_first_block;
+       next_zero_bit = ext3_find_next_zero_bit(bh->b_data,
+                               offset + EXT3_SB(sb)->s_itb_per_group,
+                               offset);
+       if (next_zero_bit >= offset + EXT3_SB(sb)->s_itb_per_group)
+               /* good bitmap for inode tables */
+               return 1;
+
+err_out:
+       ext3_error(sb, __func__,
+                       "Invalid block bitmap - "
+                       "block_group = %d, block = %lu",
+                       block_group, bitmap_blk);
+       return 0;
+}
+
 /**
  * read_block_bitmap()
  * @sb:                        super block
  * @block_group:       given block group
  *
- * Read the bitmap for a given block_group, reading into the specified
- * slot in the superblock's bitmap cache.
+ * Read the bitmap for a given block_group,and validate the
+ * bits for block/inode/inode tables are set in the bitmaps
  *
  * Return buffer_head on success or NULL in case of failure.
  */
@@ -95,17 +139,36 @@ read_block_bitmap(struct super_block *sb, unsigned int block_group)
 {
        struct ext3_group_desc * desc;
        struct buffer_head * bh = NULL;
+       ext3_fsblk_t bitmap_blk;
 
-       desc = ext3_get_group_desc (sb, block_group, NULL);
+       desc = ext3_get_group_desc(sb, block_group, NULL);
        if (!desc)
-               goto error_out;
-       bh = sb_bread(sb, le32_to_cpu(desc->bg_block_bitmap));
-       if (!bh)
-               ext3_error (sb, "read_block_bitmap",
+               return NULL;
+       bitmap_blk = le32_to_cpu(desc->bg_block_bitmap);
+       bh = sb_getblk(sb, bitmap_blk);
+       if (unlikely(!bh)) {
+               ext3_error(sb, __func__,
+                           "Cannot read block bitmap - "
+                           "block_group = %d, block_bitmap = %u",
+                           block_group, le32_to_cpu(desc->bg_block_bitmap));
+               return NULL;
+       }
+       if (likely(bh_uptodate_or_lock(bh)))
+               return bh;
+
+       if (bh_submit_read(bh) < 0) {
+               brelse(bh);
+               ext3_error(sb, __func__,
                            "Cannot read block bitmap - "
                            "block_group = %d, block_bitmap = %u",
                            block_group, le32_to_cpu(desc->bg_block_bitmap));
-error_out:
+               return NULL;
+       }
+       ext3_valid_block_bitmap(sb, desc, block_group, bh);
+       /*
+        * file system mounted not to panic on error, continue with corrupt
+        * bitmap
+        */
        return bh;
 }
 /*
@@ -144,7 +207,7 @@ restart:
 
        printk("Block Allocation Reservation Windows Map (%s):\n", fn);
        while (n) {
-               rsv = list_entry(n, struct ext3_reserve_window_node, rsv_node);
+               rsv = rb_entry(n, struct ext3_reserve_window_node, rsv_node);
                if (verbose)
                        printk("reservation window 0x%p "
                               "start:  %lu, end:  %lu\n",
@@ -170,11 +233,10 @@ restart:
                prev = rsv;
        }
        printk("Window map complete.\n");
-       if (bad)
-               BUG();
+       BUG_ON(bad);
 }
 #define rsv_window_dump(root, verbose) \
-       __rsv_window_dump((root), (verbose), __FUNCTION__)
+       __rsv_window_dump((root), (verbose), __func__)
 #else
 #define rsv_window_dump(root, verbose) do {} while (0)
 #endif
@@ -202,7 +264,7 @@ goal_in_my_reservation(struct ext3_reserve_window *rsv, ext3_grpblk_t grp_goal,
        ext3_fsblk_t group_first_block, group_last_block;
 
        group_first_block = ext3_group_first_block_no(sb, group);
-       group_last_block = group_first_block + EXT3_BLOCKS_PER_GROUP(sb) - 1;
+       group_last_block = group_first_block + (EXT3_BLOCKS_PER_GROUP(sb) - 1);
 
        if ((rsv->_rsv_start > group_last_block) ||
            (rsv->_rsv_end < group_first_block))
@@ -355,7 +417,7 @@ void ext3_init_block_alloc_info(struct inode *inode)
                rsv->rsv_start = EXT3_RESERVE_WINDOW_NOT_ALLOCATED;
                rsv->rsv_end = EXT3_RESERVE_WINDOW_NOT_ALLOCATED;
 
-               /*
+               /*
                 * if filesystem is mounted with NORESERVATION, the goal
                 * reservation window size is set to zero to indicate
                 * block reservation is off
@@ -468,11 +530,13 @@ do_more:
            in_range (block, le32_to_cpu(desc->bg_inode_table),
                      sbi->s_itb_per_group) ||
            in_range (block + count - 1, le32_to_cpu(desc->bg_inode_table),
-                     sbi->s_itb_per_group))
+                     sbi->s_itb_per_group)) {
                ext3_error (sb, "ext3_free_blocks",
                            "Freeing blocks in system zones - "
                            "Block = "E3FSBLK", count = %lu",
                            block, count);
+               goto error_return;
+       }
 
        /*
         * We are about to start releasing blocks in the bitmap,
@@ -554,7 +618,7 @@ do_more:
                if (!ext3_clear_bit_atomic(sb_bgl_lock(sbi, block_group),
                                                bit + i, bitmap_bh->b_data)) {
                        jbd_unlock_bh_state(bitmap_bh);
-                       ext3_error(sb, __FUNCTION__,
+                       ext3_error(sb, __func__,
                                "bit already cleared for block "E3FSBLK,
                                 block + i);
                        jbd_lock_bh_state(bitmap_bh);
@@ -566,11 +630,9 @@ do_more:
        jbd_unlock_bh_state(bitmap_bh);
 
        spin_lock(sb_bgl_lock(sbi, block_group));
-       desc->bg_free_blocks_count =
-               cpu_to_le16(le16_to_cpu(desc->bg_free_blocks_count) +
-                       group_freed);
+       le16_add_cpu(&desc->bg_free_blocks_count, group_freed);
        spin_unlock(sb_bgl_lock(sbi, block_group));
-       percpu_counter_mod(&sbi->s_freeblocks_counter, count);
+       percpu_counter_add(&sbi->s_freeblocks_counter, count);
 
        /* We dirtied the bitmap block */
        BUFFER_TRACE(bitmap_bh, "dirtied bitmap block");
@@ -587,7 +649,7 @@ do_more:
                count = overflow;
                goto do_more;
        }
-       sb->s_dirt = 1;
+
 error_return:
        brelse(bitmap_bh);
        ext3_std_error(sb, err);
@@ -614,7 +676,7 @@ void ext3_free_blocks(handle_t *handle, struct inode *inode,
        }
        ext3_free_blocks_sb(handle, sb, block, count, &dquot_freed_blocks);
        if (dquot_freed_blocks)
-               DQUOT_FREE_BLOCK(inode, dquot_freed_blocks);
+               vfs_dq_free_block(inode, dquot_freed_blocks);
        return;
 }
 
@@ -681,7 +743,7 @@ bitmap_search_next_usable_block(ext3_grpblk_t start, struct buffer_head *bh,
                jbd_lock_bh_state(bh);
                if (jh->b_committed_data)
                        start = ext3_find_next_zero_bit(jh->b_committed_data,
-                                                       maxblocks, next);
+                                                       maxblocks, next);
                jbd_unlock_bh_state(bh);
        }
        return -1;
@@ -730,7 +792,7 @@ find_next_usable_block(ext3_grpblk_t start, struct buffer_head *bh,
                here = 0;
 
        p = ((char *)bh->b_data) + (here >> 3);
-       r = memscan(p, 0, (maxblocks - here + 7) >> 3);
+       r = memscan(p, 0, ((maxblocks + 7) >> 3) - (here >> 3));
        next = (r - ((char *)bh->b_data)) << 3;
 
        if (next < maxblocks && next >= start && ext3_test_allocatable(next, bh))
@@ -790,10 +852,10 @@ claim_block(spinlock_t *lock, ext3_grpblk_t block, struct buffer_head *bh)
  * and at last, allocate the blocks by claiming the found free bit as allocated.
  *
  * To set the range of this allocation:
- *     if there is a reservation window, only try to allocate block(s) from the
+ *     if there is a reservation window, only try to allocate block(s) from the
  *     file's own reservation window;
  *     Otherwise, the allocation range starts from the give goal block, ends at
- *     the block group's last block.
+ *     the block group's last block.
  *
  * If we failed to allocate the desired block then we may end up crossing to a
  * new bitmap.  In that case we must release write access to the old one via
@@ -880,12 +942,12 @@ fail_access:
 }
 
 /**
- *     find_next_reservable_window():
+ *     find_next_reservable_window():
  *             find a reservable space within the given range.
  *             It does not allocate the reservation window for now:
  *             alloc_new_reservation() will do the work later.
  *
- *     @search_head: the head of the searching list;
+ *     @search_head: the head of the searching list;
  *             This is not necessarily the list head of the whole filesystem
  *
  *             We have both head and start_block to assist the search
@@ -893,12 +955,12 @@ fail_access:
  *             but we will shift to the place where start_block is,
  *             then start from there, when looking for a reservable space.
  *
- *     @size: the target new reservation window size
+ *     @size: the target new reservation window size
  *
- *     @group_first_block: the first block we consider to start
+ *     @group_first_block: the first block we consider to start
  *                     the real search from
  *
- *     @last_block:
+ *     @last_block:
  *             the maximum block number that our goal reservable space
  *             could start from. This is normally the last block in this
  *             group. The search will end when we found the start of next
@@ -906,10 +968,10 @@ fail_access:
  *             This could handle the cross boundary reservation window
  *             request.
  *
- *     basically we search from the given range, rather than the whole
- *     reservation double linked list, (start_block, last_block)
- *     to find a free region that is of my size and has not
- *     been reserved.
+ *     basically we search from the given range, rather than the whole
+ *     reservation double linked list, (start_block, last_block)
+ *     to find a free region that is of my size and has not
+ *     been reserved.
  *
  */
 static int find_next_reservable_window(
@@ -949,7 +1011,7 @@ static int find_next_reservable_window(
 
                prev = rsv;
                next = rb_next(&rsv->rsv_node);
-               rsv = list_entry(next,struct ext3_reserve_window_node,rsv_node);
+               rsv = rb_entry(next,struct ext3_reserve_window_node,rsv_node);
 
                /*
                 * Reached the last reservation, we can just append to the
@@ -962,7 +1024,7 @@ static int find_next_reservable_window(
                        /*
                         * Found a reserveable space big enough.  We could
                         * have a reservation across the group boundary here
-                        */
+                        */
                        break;
                }
        }
@@ -998,7 +1060,7 @@ static int find_next_reservable_window(
 }
 
 /**
- *     alloc_new_reservation()--allocate a new reservation window
+ *     alloc_new_reservation()--allocate a new reservation window
  *
  *             To make a new reservation, we search part of the filesystem
  *             reservation list (the list that inside the group). We try to
@@ -1047,7 +1109,7 @@ static int alloc_new_reservation(struct ext3_reserve_window_node *my_rsv,
        spinlock_t *rsv_lock = &EXT3_SB(sb)->s_rsv_window_lock;
 
        group_first_block = ext3_group_first_block_no(sb, group);
-       group_end_block = group_first_block + EXT3_BLOCKS_PER_GROUP(sb) - 1;
+       group_end_block = group_first_block + (EXT3_BLOCKS_PER_GROUP(sb) - 1);
 
        if (grp_goal < 0)
                start_block = group_first_block;
@@ -1148,7 +1210,7 @@ retry:
         * check if the first free block is within the
         * free space we just reserved
         */
-       if (start_block >= my_rsv->rsv_start && start_block < my_rsv->rsv_end)
+       if (start_block >= my_rsv->rsv_start && start_block <= my_rsv->rsv_end)
                return 0;               /* success */
        /*
         * if the first free bit we found is out of the reservable space
@@ -1193,7 +1255,7 @@ static void try_to_extend_reservation(struct ext3_reserve_window_node *my_rsv,
        if (!next)
                my_rsv->rsv_end += size;
        else {
-               next_rsv = list_entry(next, struct ext3_reserve_window_node, rsv_node);
+               next_rsv = rb_entry(next, struct ext3_reserve_window_node, rsv_node);
 
                if ((next_rsv->rsv_start - my_rsv->rsv_end - 1) >= size)
                        my_rsv->rsv_end += size;
@@ -1239,7 +1301,7 @@ ext3_try_to_allocate_with_rsv(struct super_block *sb, handle_t *handle,
                        struct ext3_reserve_window_node * my_rsv,
                        unsigned long *count, int *errp)
 {
-       ext3_fsblk_t group_first_block;
+       ext3_fsblk_t group_first_block, group_last_block;
        ext3_grpblk_t ret = 0;
        int fatal;
        unsigned long num = *count;
@@ -1271,11 +1333,12 @@ ext3_try_to_allocate_with_rsv(struct super_block *sb, handle_t *handle,
        }
        /*
         * grp_goal is a group relative block number (if there is a goal)
-        * 0 < grp_goal < EXT3_BLOCKS_PER_GROUP(sb)
+        * 0 <= grp_goal < EXT3_BLOCKS_PER_GROUP(sb)
         * first block is a filesystem wide block number
         * first block is the block number of the first block in this group
         */
        group_first_block = ext3_group_first_block_no(sb, group);
+       group_last_block = group_first_block + (EXT3_BLOCKS_PER_GROUP(sb) - 1);
 
        /*
         * Basically we will allocate a new block from inode's reservation
@@ -1306,14 +1369,17 @@ ext3_try_to_allocate_with_rsv(struct super_block *sb, handle_t *handle,
                        if (!goal_in_my_reservation(&my_rsv->rsv_window,
                                                        grp_goal, group, sb))
                                grp_goal = -1;
-               } else if (grp_goal > 0 &&
-                         (my_rsv->rsv_end-grp_goal+1) < *count)
-                       try_to_extend_reservation(my_rsv, sb,
-                                       *count-my_rsv->rsv_end + grp_goal - 1);
-
-               if ((my_rsv->rsv_start >= group_first_block +
-                                       EXT3_BLOCKS_PER_GROUP(sb))
-                   || (my_rsv->rsv_end < group_first_block)) {
+               } else if (grp_goal >= 0) {
+                       int curr = my_rsv->rsv_end -
+                                       (grp_goal + group_first_block) + 1;
+
+                       if (curr < *count)
+                               try_to_extend_reservation(my_rsv, sb,
+                                                       *count - curr);
+               }
+
+               if ((my_rsv->rsv_start > group_last_block) ||
+                               (my_rsv->rsv_end < group_first_block)) {
                        rsv_window_dump(&EXT3_SB(sb)->s_rsv_window_root, 1);
                        BUG();
                }
@@ -1356,7 +1422,7 @@ static int ext3_has_free_blocks(struct ext3_sb_info *sbi)
        free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
        root_blocks = le32_to_cpu(sbi->s_es->s_r_blocks_count);
        if (free_blocks < root_blocks + 1 && !capable(CAP_SYS_RESOURCE) &&
-               sbi->s_resuid != current->fsuid &&
+               sbi->s_resuid != current_fsuid() &&
                (sbi->s_resgid == 0 || !in_group_p (sbi->s_resgid))) {
                return 0;
        }
@@ -1436,7 +1502,7 @@ ext3_fsblk_t ext3_new_blocks(handle_t *handle, struct inode *inode,
        /*
         * Check quota for allocation of this block.
         */
-       if (DQUOT_ALLOC_BLOCK(inode, num)) {
+       if (vfs_dq_alloc_block(inode, num)) {
                *errp = -EDQUOT;
                return 0;
        }
@@ -1481,6 +1547,7 @@ retry_alloc:
         * turn off reservation for this allocation
         */
        if (my_rsv && (free_blocks < windowsz)
+               && (free_blocks > 0)
                && (rsv_is_empty(&my_rsv->rsv_window)))
                my_rsv = NULL;
 
@@ -1504,24 +1571,22 @@ retry_alloc:
 
        /*
         * Now search the rest of the groups.  We assume that
-        * i and gdp correctly point to the last group visited.
+        * group_no and gdp correctly point to the last group visited.
         */
        for (bgi = 0; bgi < ngroups; bgi++) {
                group_no++;
                if (group_no >= ngroups)
                        group_no = 0;
                gdp = ext3_get_group_desc(sb, group_no, &gdp_bh);
-               if (!gdp) {
-                       *errp = -EIO;
-                       goto out;
-               }
+               if (!gdp)
+                       goto io_error;
                free_blocks = le16_to_cpu(gdp->bg_free_blocks_count);
                /*
                 * skip this group if the number of
                 * free blocks is less than half of the reservation
                 * window size.
                 */
-               if (free_blocks <= (windowsz/2))
+               if (my_rsv && (free_blocks <= (windowsz/2)))
                        continue;
 
                brelse(bitmap_bh);
@@ -1548,6 +1613,7 @@ retry_alloc:
         */
        if (my_rsv) {
                my_rsv = NULL;
+               windowsz = 0;
                group_no = goal_group;
                goto retry_alloc;
        }
@@ -1572,11 +1638,17 @@ allocated:
            in_range(ret_block, le32_to_cpu(gdp->bg_inode_table),
                      EXT3_SB(sb)->s_itb_per_group) ||
            in_range(ret_block + num - 1, le32_to_cpu(gdp->bg_inode_table),
-                     EXT3_SB(sb)->s_itb_per_group))
+                     EXT3_SB(sb)->s_itb_per_group)) {
                ext3_error(sb, "ext3_new_block",
                            "Allocating block in system zone - "
                            "blocks from "E3FSBLK", length %lu",
                             ret_block, num);
+               /*
+                * claim_block() marked the blocks we allocated as in use. So we
+                * may want to selectively mark some of the blocks as free.
+                */
+               goto retry_alloc;
+       }
 
        performed_allocation = 1;
 
@@ -1601,7 +1673,7 @@ allocated:
                        if (ext3_test_bit(grp_alloc_blk+i,
                                        bh2jh(bitmap_bh)->b_committed_data)) {
                                printk("%s: block was unexpectedly set in "
-                                       "b_committed_data\n", __FUNCTION__);
+                                       "b_committed_data\n", __func__);
                        }
                }
        }
@@ -1627,23 +1699,21 @@ allocated:
                        ret_block, goal_hits, goal_attempts);
 
        spin_lock(sb_bgl_lock(sbi, group_no));
-       gdp->bg_free_blocks_count =
-                       cpu_to_le16(le16_to_cpu(gdp->bg_free_blocks_count)-num);
+       le16_add_cpu(&gdp->bg_free_blocks_count, -num);
        spin_unlock(sb_bgl_lock(sbi, group_no));
-       percpu_counter_mod(&sbi->s_freeblocks_counter, -num);
+       percpu_counter_sub(&sbi->s_freeblocks_counter, num);
 
        BUFFER_TRACE(gdp_bh, "journal_dirty_metadata for group descriptor");
        err = ext3_journal_dirty_metadata(handle, gdp_bh);
        if (!fatal)
                fatal = err;
 
-       sb->s_dirt = 1;
        if (fatal)
                goto out;
 
        *errp = 0;
        brelse(bitmap_bh);
-       DQUOT_FREE_BLOCK(inode, *count-num);
+       vfs_dq_free_block(inode, *count-num);
        *count = num;
        return ret_block;
 
@@ -1658,7 +1728,7 @@ out:
         * Undo the block allocation
         */
        if (!performed_allocation)
-               DQUOT_FREE_BLOCK(inode, *count);
+               vfs_dq_free_block(inode, *count);
        brelse(bitmap_bh);
        return 0;
 }
@@ -1730,14 +1800,6 @@ ext3_fsblk_t ext3_count_free_blocks(struct super_block *sb)
 #endif
 }
 
-static inline int
-block_in_use(ext3_fsblk_t block, struct super_block *sb, unsigned char *map)
-{
-       return ext3_test_bit ((block -
-               le32_to_cpu(EXT3_SB(sb)->s_es->s_first_data_block)) %
-                        EXT3_BLOCKS_PER_GROUP(sb), map);
-}
-
 static inline int test_root(int a, int b)
 {
        int num = b;
@@ -1787,11 +1849,7 @@ static unsigned long ext3_bg_num_gdb_meta(struct super_block *sb, int group)
 
 static unsigned long ext3_bg_num_gdb_nometa(struct super_block *sb, int group)
 {
-       if (EXT3_HAS_RO_COMPAT_FEATURE(sb,
-                               EXT3_FEATURE_RO_COMPAT_SPARSE_SUPER) &&
-                       !ext3_group_sparse(group))
-               return 0;
-       return EXT3_SB(sb)->s_gdb_count;
+       return ext3_bg_has_super(sb, group) ? EXT3_SB(sb)->s_gdb_count : 0;
 }
 
 /**