Merge commit 'v2.6.28-rc2' into core/locking

Conflicts:
	arch/um/include/asm/system.h

1 files changed, 100 insertions, 1369 deletions

diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index e9fa960ba6da..b9821be709bd 100644
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -83,6 +83,7 @@ static int ext4_group_used_meta_blocks(struct super_block *sb,
         }
         return used_blocks;
 }
+
 /* Initializes an uninitialized block bitmap if given, and returns the
  * number of blocks free in the group. */
 unsigned ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh,
@@ -132,7 +133,7 @@ unsigned ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh,
                  */
                 group_blocks = ext4_blocks_count(sbi->s_es) -
                         le32_to_cpu(sbi->s_es->s_first_data_block) -
-                        (EXT4_BLOCKS_PER_GROUP(sb) * (sbi->s_groups_count -1));
+                        (EXT4_BLOCKS_PER_GROUP(sb) * (sbi->s_groups_count - 1));
         } else {
                 group_blocks = EXT4_BLOCKS_PER_GROUP(sb);
         }
@@ -200,20 +201,20 @@ unsigned ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh,
  * @bh:                 pointer to the buffer head to store the block
  *                      group descriptor
  */
-struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
+struct ext4_group_desc * ext4_get_group_desc(struct super_block *sb,
                                              ext4_group_t block_group,
-                                             struct buffer_head ** bh)
+                                             struct buffer_head **bh)
 {
         unsigned long group_desc;
         unsigned long offset;
-        struct ext4_group_desc * desc;
+        struct ext4_group_desc *desc;
         struct ext4_sb_info *sbi = EXT4_SB(sb);
 
         if (block_group >= sbi->s_groups_count) {
-                ext4_error (sb, "ext4_get_group_desc",
-                            "block_group >= groups_count - "
-                            "block_group = %lu, groups_count = %lu",
-                            block_group, sbi->s_groups_count);
+                ext4_error(sb, "ext4_get_group_desc",
+                           "block_group >= groups_count - "
+                           "block_group = %lu, groups_count = %lu",
+                           block_group, sbi->s_groups_count);
 
                 return NULL;
         }
@@ -222,10 +223,10 @@ struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
         group_desc = block_group >> EXT4_DESC_PER_BLOCK_BITS(sb);
         offset = block_group & (EXT4_DESC_PER_BLOCK(sb) - 1);
         if (!sbi->s_group_desc[group_desc]) {
-                ext4_error (sb, "ext4_get_group_desc",
-                            "Group descriptor not loaded - "
-                            "block_group = %lu, group_desc = %lu, desc = %lu",
-                             block_group, group_desc, offset);
+                ext4_error(sb, "ext4_get_group_desc",
+                           "Group descriptor not loaded - "
+                           "block_group = %lu, group_desc = %lu, desc = %lu",
+                           block_group, group_desc, offset);
                 return NULL;
         }
 
@@ -302,8 +303,8 @@ err_out:
 struct buffer_head *
 ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group)
 {
-        struct ext4_group_desc * desc;
-        struct buffer_head * bh = NULL;
+        struct ext4_group_desc *desc;
+        struct buffer_head *bh = NULL;
         ext4_fsblk_t bitmap_blk;
 
         desc = ext4_get_group_desc(sb, block_group, NULL);
@@ -318,9 +319,11 @@ ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group)
                             block_group, bitmap_blk);
                 return NULL;
         }
-        if (bh_uptodate_or_lock(bh))
+        if (buffer_uptodate(bh) &&
+            !(desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)))
                 return bh;
 
+        lock_buffer(bh);
         spin_lock(sb_bgl_lock(EXT4_SB(sb), block_group));
         if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
                 ext4_init_block_bitmap(sb, bh, block_group, desc);
@@ -345,301 +348,6 @@ ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group)
          */
         return bh;
 }
-/*
- * The reservation window structure operations
- * --------------------------------------------
- * Operations include:
- * dump, find, add, remove, is_empty, find_next_reservable_window, etc.
- *
- * We use a red-black tree to represent per-filesystem reservation
- * windows.
- *
- */
-
-/**
- * __rsv_window_dump() -- Dump the filesystem block allocation reservation map
- * @rb_root:            root of per-filesystem reservation rb tree
- * @verbose:            verbose mode
- * @fn:                 function which wishes to dump the reservation map
- *
- * If verbose is turned on, it will print the whole block reservation
- * windows(start, end). Otherwise, it will only print out the "bad" windows,
- * those windows that overlap with their immediate neighbors.
- */
-#if 1
-static void __rsv_window_dump(struct rb_root *root, int verbose,
-                              const char *fn)
-{
-        struct rb_node *n;
-        struct ext4_reserve_window_node *rsv, *prev;
-        int bad;
-
-restart:
-        n = rb_first(root);
-        bad = 0;
-        prev = NULL;
-
-        printk("Block Allocation Reservation Windows Map (%s):\n", fn);
-        while (n) {
-                rsv = rb_entry(n, struct ext4_reserve_window_node, rsv_node);
-                if (verbose)
-                        printk("reservation window 0x%p "
-                               "start:  %llu, end:  %llu\n",
-                               rsv, rsv->rsv_start, rsv->rsv_end);
-                if (rsv->rsv_start && rsv->rsv_start >= rsv->rsv_end) {
-                        printk("Bad reservation %p (start >= end)\n",
-                               rsv);
-                        bad = 1;
-                }
-                if (prev && prev->rsv_end >= rsv->rsv_start) {
-                        printk("Bad reservation %p (prev->end >= start)\n",
-                               rsv);
-                        bad = 1;
-                }
-                if (bad) {
-                        if (!verbose) {
-                                printk("Restarting reservation walk in verbose mode\n");
-                                verbose = 1;
-                                goto restart;
-                        }
-                }
-                n = rb_next(n);
-                prev = rsv;
-        }
-        printk("Window map complete.\n");
-        BUG_ON(bad);
-}
-#define rsv_window_dump(root, verbose) \
-        __rsv_window_dump((root), (verbose), __func__)
-#else
-#define rsv_window_dump(root, verbose) do {} while (0)
-#endif
-
-/**
- * goal_in_my_reservation()
- * @rsv:                inode's reservation window
- * @grp_goal:           given goal block relative to the allocation block group
- * @group:              the current allocation block group
- * @sb:                 filesystem super block
- *
- * Test if the given goal block (group relative) is within the file's
- * own block reservation window range.
- *
- * If the reservation window is outside the goal allocation group, return 0;
- * grp_goal (given goal block) could be -1, which means no specific
- * goal block. In this case, always return 1.
- * If the goal block is within the reservation window, return 1;
- * otherwise, return 0;
- */
-static int
-goal_in_my_reservation(struct ext4_reserve_window *rsv, ext4_grpblk_t grp_goal,
-                        ext4_group_t group, struct super_block *sb)
-{
-        ext4_fsblk_t group_first_block, group_last_block;
-
-        group_first_block = ext4_group_first_block_no(sb, group);
-        group_last_block = group_first_block + (EXT4_BLOCKS_PER_GROUP(sb) - 1);
-
-        if ((rsv->_rsv_start > group_last_block) ||
-            (rsv->_rsv_end < group_first_block))
-                return 0;
-        if ((grp_goal >= 0) && ((grp_goal + group_first_block < rsv->_rsv_start)
-                || (grp_goal + group_first_block > rsv->_rsv_end)))
-                return 0;
-        return 1;
-}
-
-/**
- * search_reserve_window()
- * @rb_root:            root of reservation tree
- * @goal:               target allocation block
- *
- * Find the reserved window which includes the goal, or the previous one
- * if the goal is not in any window.
- * Returns NULL if there are no windows or if all windows start after the goal.
- */
-static struct ext4_reserve_window_node *
-search_reserve_window(struct rb_root *root, ext4_fsblk_t goal)
-{
-        struct rb_node *n = root->rb_node;
-        struct ext4_reserve_window_node *rsv;
-
-        if (!n)
-                return NULL;
-
-        do {
-                rsv = rb_entry(n, struct ext4_reserve_window_node, rsv_node);
-
-                if (goal < rsv->rsv_start)
-                        n = n->rb_left;
-                else if (goal > rsv->rsv_end)
-                        n = n->rb_right;
-                else
-                        return rsv;
-        } while (n);
-        /*
-         * We've fallen off the end of the tree: the goal wasn't inside
-         * any particular node.  OK, the previous node must be to one
-         * side of the interval containing the goal.  If it's the RHS,
-         * we need to back up one.
-         */
-        if (rsv->rsv_start > goal) {
-                n = rb_prev(&rsv->rsv_node);
-                rsv = rb_entry(n, struct ext4_reserve_window_node, rsv_node);
-        }
-        return rsv;
-}
-
-/**
- * ext4_rsv_window_add() -- Insert a window to the block reservation rb tree.
- * @sb:                 super block
- * @rsv:                reservation window to add
- *
- * Must be called with rsv_lock hold.
- */
-void ext4_rsv_window_add(struct super_block *sb,
-                    struct ext4_reserve_window_node *rsv)
-{
-        struct rb_root *root = &EXT4_SB(sb)->s_rsv_window_root;
-        struct rb_node *node = &rsv->rsv_node;
-        ext4_fsblk_t start = rsv->rsv_start;
-
-        struct rb_node ** p = &root->rb_node;
-        struct rb_node * parent = NULL;
-        struct ext4_reserve_window_node *this;
-
-        while (*p)
-        {
-                parent = *p;
-                this = rb_entry(parent, struct ext4_reserve_window_node, rsv_node);
-
-                if (start < this->rsv_start)
-                        p = &(*p)->rb_left;
-                else if (start > this->rsv_end)
-                        p = &(*p)->rb_right;
-                else {
-                        rsv_window_dump(root, 1);
-                        BUG();
-                }
-        }
-
-        rb_link_node(node, parent, p);
-        rb_insert_color(node, root);
-}
-
-/**
- * ext4_rsv_window_remove() -- unlink a window from the reservation rb tree
- * @sb:                 super block
- * @rsv:                reservation window to remove
- *
- * Mark the block reservation window as not allocated, and unlink it
- * from the filesystem reservation window rb tree. Must be called with
- * rsv_lock hold.
- */
-static void rsv_window_remove(struct super_block *sb,
-                              struct ext4_reserve_window_node *rsv)
-{
-        rsv->rsv_start = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
-        rsv->rsv_end = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
-        rsv->rsv_alloc_hit = 0;
-        rb_erase(&rsv->rsv_node, &EXT4_SB(sb)->s_rsv_window_root);
-}
-
-/*
- * rsv_is_empty() -- Check if the reservation window is allocated.
- * @rsv:                given reservation window to check
- *
- * returns 1 if the end block is EXT4_RESERVE_WINDOW_NOT_ALLOCATED.
- */
-static inline int rsv_is_empty(struct ext4_reserve_window *rsv)
-{
-        /* a valid reservation end block could not be 0 */
-        return rsv->_rsv_end == EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
-}
-
-/**
- * ext4_init_block_alloc_info()
- * @inode:              file inode structure
- *
- * Allocate and initialize the  reservation window structure, and
- * link the window to the ext4 inode structure at last
- *
- * The reservation window structure is only dynamically allocated
- * and linked to ext4 inode the first time the open file
- * needs a new block. So, before every ext4_new_block(s) call, for
- * regular files, we should check whether the reservation window
- * structure exists or not. In the latter case, this function is called.
- * Fail to do so will result in block reservation being turned off for that
- * open file.
- *
- * This function is called from ext4_get_blocks_handle(), also called
- * when setting the reservation window size through ioctl before the file
- * is open for write (needs block allocation).
- *
- * Needs down_write(i_data_sem) protection prior to call this function.
- */
-void ext4_init_block_alloc_info(struct inode *inode)
-{
-        struct ext4_inode_info *ei = EXT4_I(inode);
-        struct ext4_block_alloc_info *block_i = ei->i_block_alloc_info;
-        struct super_block *sb = inode->i_sb;
-
-        block_i = kmalloc(sizeof(*block_i), GFP_NOFS);
-        if (block_i) {
-                struct ext4_reserve_window_node *rsv = &block_i->rsv_window_node;
-
-                rsv->rsv_start = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
-                rsv->rsv_end = EXT4_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
-                 */
-                if (!test_opt(sb, RESERVATION))
-                        rsv->rsv_goal_size = 0;
-                else
-                        rsv->rsv_goal_size = EXT4_DEFAULT_RESERVE_BLOCKS;
-                rsv->rsv_alloc_hit = 0;
-                block_i->last_alloc_logical_block = 0;
-                block_i->last_alloc_physical_block = 0;
-        }
-        ei->i_block_alloc_info = block_i;
-}
-
-/**
- * ext4_discard_reservation()
- * @inode:              inode
- *
- * Discard(free) block reservation window on last file close, or truncate
- * or at last iput().
- *
- * It is being called in three cases:
- *      ext4_release_file(): last writer close the file
- *      ext4_clear_inode(): last iput(), when nobody link to this file.
- *      ext4_truncate(): when the block indirect map is about to change.
- *
- */
-void ext4_discard_reservation(struct inode *inode)
-{
-        struct ext4_inode_info *ei = EXT4_I(inode);
-        struct ext4_block_alloc_info *block_i = ei->i_block_alloc_info;
-        struct ext4_reserve_window_node *rsv;
-        spinlock_t *rsv_lock = &EXT4_SB(inode->i_sb)->s_rsv_window_lock;
-
-        ext4_mb_discard_inode_preallocations(inode);
-
-        if (!block_i)
-                return;
-
-        rsv = &block_i->rsv_window_node;
-        if (!rsv_is_empty(&rsv->rsv_window)) {
-                spin_lock(rsv_lock);
-                if (!rsv_is_empty(&rsv->rsv_window))
-                        rsv_window_remove(inode->i_sb, rsv);
-                spin_unlock(rsv_lock);
-        }
-}
 
 /**
  * ext4_free_blocks_sb() -- Free given blocks and update quota
@@ -648,6 +356,13 @@ void ext4_discard_reservation(struct inode *inode)
  * @block:                      start physcial block to free
  * @count:                      number of blocks to free
  * @pdquot_freed_blocks:        pointer to quota
+ *
+ * XXX This function is only used by the on-line resizing code, which
+ * should probably be fixed up to call the mballoc variant.  There
+ * this needs to be cleaned up later; in fact, I'm not convinced this
+ * is 100% correct in the face of the mballoc code.  The online resizing
+ * code needs to be fixed up to more tightly (and correctly) interlock
+ * with the mballoc code.
  */
 void ext4_free_blocks_sb(handle_t *handle, struct super_block *sb,
                          ext4_fsblk_t block, unsigned long count,
@@ -659,8 +374,8 @@ void ext4_free_blocks_sb(handle_t *handle, struct super_block *sb,
         ext4_grpblk_t bit;
         unsigned long i;
         unsigned long overflow;
-        struct ext4_group_desc * desc;
-        struct ext4_super_block * es;
+        struct ext4_group_desc *desc;
+        struct ext4_super_block *es;
         struct ext4_sb_info *sbi;
         int err = 0, ret;
         ext4_grpblk_t group_freed;
@@ -671,13 +386,13 @@ void ext4_free_blocks_sb(handle_t *handle, struct super_block *sb,
         if (block < le32_to_cpu(es->s_first_data_block) ||
             block + count < block ||
             block + count > ext4_blocks_count(es)) {
-                ext4_error (sb, "ext4_free_blocks",
-                            "Freeing blocks not in datazone - "
-                            "block = %llu, count = %lu", block, count);
+                ext4_error(sb, "ext4_free_blocks",
+                           "Freeing blocks not in datazone - "
+                           "block = %llu, count = %lu", block, count);
                 goto error_return;
         }
 
-        ext4_debug ("freeing block(s) %llu-%llu\n", block, block + count - 1);
+        ext4_debug("freeing block(s) %llu-%llu\n", block, block + count - 1);
 
 do_more:
         overflow = 0;
@@ -694,7 +409,7 @@ do_more:
         bitmap_bh = ext4_read_block_bitmap(sb, block_group);
         if (!bitmap_bh)
                 goto error_return;
-        desc = ext4_get_group_desc (sb, block_group, &gd_bh);
+        desc = ext4_get_group_desc(sb, block_group, &gd_bh);
         if (!desc)
                 goto error_return;
 
@@ -703,10 +418,10 @@ do_more:
             in_range(block, ext4_inode_table(sb, desc), sbi->s_itb_per_group) ||
             in_range(block + count - 1, ext4_inode_table(sb, desc),
                      sbi->s_itb_per_group)) {
-                ext4_error (sb, "ext4_free_blocks",
-                            "Freeing blocks in system zones - "
-                            "Block = %llu, count = %lu",
-                            block, count);
+                ext4_error(sb, "ext4_free_blocks",
+                           "Freeing blocks in system zones - "
+                           "Block = %llu, count = %lu",
+                           block, count);
                 goto error_return;
         }
 
@@ -848,759 +563,71 @@ void ext4_free_blocks(handle_t *handle, struct inode *inode,
                         ext4_fsblk_t block, unsigned long count,
                         int metadata)
 {
-        struct super_block * sb;
+        struct super_block *sb;
         unsigned long dquot_freed_blocks;
 
         /* this isn't the right place to decide whether block is metadata
          * inode.c/extents.c knows better, but for safety ... */
-        if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode) ||
-                        ext4_should_journal_data(inode))
+        if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
+                metadata = 1;
+
+        /* We need to make sure we don't reuse
+         * block released untill the transaction commit.
+         * writeback mode have weak data consistency so
+         * don't force data as metadata when freeing block
+         * for writeback mode.
+         */
+        if (metadata == 0 && !ext4_should_writeback_data(inode))
                 metadata = 1;
 
         sb = inode->i_sb;
 
-        if (!test_opt(sb, MBALLOC) || !EXT4_SB(sb)->s_group_info)
-                ext4_free_blocks_sb(handle, sb, block, count,
-                                                &dquot_freed_blocks);
-        else
-                ext4_mb_free_blocks(handle, inode, block, count,
-                                                metadata, &dquot_freed_blocks);
+        ext4_mb_free_blocks(handle, inode, block, count,
+                            metadata, &dquot_freed_blocks);
         if (dquot_freed_blocks)
                 DQUOT_FREE_BLOCK(inode, dquot_freed_blocks);
         return;
 }
 
-/**
- * ext4_test_allocatable()
- * @nr:                 given allocation block group
- * @bh:                 bufferhead contains the bitmap of the given block group
- *
- * For ext4 allocations, we must not reuse any blocks which are
- * allocated in the bitmap buffer's "last committed data" copy.  This
- * prevents deletes from freeing up the page for reuse until we have
- * committed the delete transaction.
- *
- * If we didn't do this, then deleting something and reallocating it as
- * data would allow the old block to be overwritten before the
- * transaction committed (because we force data to disk before commit).
- * This would lead to corruption if we crashed between overwriting the
- * data and committing the delete.
- *
- * @@@ We may want to make this allocation behaviour conditional on
- * data-writes at some point, and disable it for metadata allocations or
- * sync-data inodes.
- */
-static int ext4_test_allocatable(ext4_grpblk_t nr, struct buffer_head *bh)
+int ext4_claim_free_blocks(struct ext4_sb_info *sbi,
+                                                s64 nblocks)
 {
-        int ret;
-        struct journal_head *jh = bh2jh(bh);
-
-        if (ext4_test_bit(nr, bh->b_data))
-                return 0;
-
-        jbd_lock_bh_state(bh);
-        if (!jh->b_committed_data)
-                ret = 1;
-        else
-                ret = !ext4_test_bit(nr, jh->b_committed_data);
-        jbd_unlock_bh_state(bh);
-        return ret;
-}
+        s64 free_blocks, dirty_blocks;
+        s64 root_blocks = 0;
+        struct percpu_counter *fbc = &sbi->s_freeblocks_counter;
+        struct percpu_counter *dbc = &sbi->s_dirtyblocks_counter;
 
-/**
- * bitmap_search_next_usable_block()
- * @start:              the starting block (group relative) of the search
- * @bh:                 bufferhead contains the block group bitmap
- * @maxblocks:          the ending block (group relative) of the reservation
- *
- * The bitmap search --- search forward alternately through the actual
- * bitmap on disk and the last-committed copy in journal, until we find a
- * bit free in both bitmaps.
- */
-static ext4_grpblk_t
-bitmap_search_next_usable_block(ext4_grpblk_t start, struct buffer_head *bh,
-                                        ext4_grpblk_t maxblocks)
-{
-        ext4_grpblk_t next;
-        struct journal_head *jh = bh2jh(bh);
-
-        while (start < maxblocks) {
-                next = ext4_find_next_zero_bit(bh->b_data, maxblocks, start);
-                if (next >= maxblocks)
-                        return -1;
-                if (ext4_test_allocatable(next, bh))
-                        return next;
-                jbd_lock_bh_state(bh);
-                if (jh->b_committed_data)
-                        start = ext4_find_next_zero_bit(jh->b_committed_data,
-                                                        maxblocks, next);
-                jbd_unlock_bh_state(bh);
-        }
-        return -1;
-}
+        free_blocks  = percpu_counter_read_positive(fbc);
+        dirty_blocks = percpu_counter_read_positive(dbc);
 
-/**
- * find_next_usable_block()
- * @start:              the starting block (group relative) to find next
- *                      allocatable block in bitmap.
- * @bh:                 bufferhead contains the block group bitmap
- * @maxblocks:          the ending block (group relative) for the search
- *
- * Find an allocatable block in a bitmap.  We honor both the bitmap and
- * its last-committed copy (if that exists), and perform the "most
- * appropriate allocation" algorithm of looking for a free block near
- * the initial goal; then for a free byte somewhere in the bitmap; then
- * for any free bit in the bitmap.
- */
-static ext4_grpblk_t
-find_next_usable_block(ext4_grpblk_t start, struct buffer_head *bh,
-                        ext4_grpblk_t maxblocks)
-{
-        ext4_grpblk_t here, next;
-        char *p, *r;
-
-        if (start > 0) {
-                /*
-                 * The goal was occupied; search forward for a free
-                 * block within the next XX blocks.
-                 *
-                 * end_goal is more or less random, but it has to be
-                 * less than EXT4_BLOCKS_PER_GROUP. Aligning up to the
-                 * next 64-bit boundary is simple..
-                 */
-                ext4_grpblk_t end_goal = (start + 63) & ~63;
-                if (end_goal > maxblocks)
-                        end_goal = maxblocks;
-                here = ext4_find_next_zero_bit(bh->b_data, end_goal, start);
-                if (here < end_goal && ext4_test_allocatable(here, bh))
-                        return here;
-                ext4_debug("Bit not found near goal\n");
-        }
-
-        here = start;
-        if (here < 0)
-                here = 0;
-
-        p = ((char *)bh->b_data) + (here >> 3);
-        r = memscan(p, 0, ((maxblocks + 7) >> 3) - (here >> 3));
-        next = (r - ((char *)bh->b_data)) << 3;
-
-        if (next < maxblocks && next >= start && ext4_test_allocatable(next, bh))
-                return next;
-
-        /*
-         * The bitmap search --- search forward alternately through the actual
-         * bitmap and the last-committed copy until we find a bit free in
-         * both
-         */
-        here = bitmap_search_next_usable_block(here, bh, maxblocks);
-        return here;
-}
-
-/**
- * claim_block()
- * @block:              the free block (group relative) to allocate
- * @bh:                 the bufferhead containts the block group bitmap
- *
- * We think we can allocate this block in this bitmap.  Try to set the bit.
- * If that succeeds then check that nobody has allocated and then freed the
- * block since we saw that is was not marked in b_committed_data.  If it _was_
- * allocated and freed then clear the bit in the bitmap again and return
- * zero (failure).
- */
-static inline int
-claim_block(spinlock_t *lock, ext4_grpblk_t block, struct buffer_head *bh)
-{
-        struct journal_head *jh = bh2jh(bh);
-        int ret;
-
-        if (ext4_set_bit_atomic(lock, block, bh->b_data))
-                return 0;
-        jbd_lock_bh_state(bh);
-        if (jh->b_committed_data && ext4_test_bit(block,jh->b_committed_data)) {
-                ext4_clear_bit_atomic(lock, block, bh->b_data);
-                ret = 0;
-        } else {
-                ret = 1;
-        }
-        jbd_unlock_bh_state(bh);
-        return ret;
-}
-
-/**
- * ext4_try_to_allocate()
- * @sb:                 superblock
- * @handle:             handle to this transaction
- * @group:              given allocation block group
- * @bitmap_bh:          bufferhead holds the block bitmap
- * @grp_goal:           given target block within the group
- * @count:              target number of blocks to allocate
- * @my_rsv:             reservation window
- *
- * Attempt to allocate blocks within a give range. Set the range of allocation
- * first, then find the first free bit(s) from the bitmap (within the range),
- * 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
- *      file's own reservation window;
- *      Otherwise, the allocation range starts from the give goal block, ends at
- *      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
- * ext4_journal_release_buffer(), else we'll run out of credits.
- */
-static ext4_grpblk_t
-ext4_try_to_allocate(struct super_block *sb, handle_t *handle,
-                        ext4_group_t group, struct buffer_head *bitmap_bh,
-                        ext4_grpblk_t grp_goal, unsigned long *count,
-                        struct ext4_reserve_window *my_rsv)
-{
-        ext4_fsblk_t group_first_block;
-        ext4_grpblk_t start, end;
-        unsigned long num = 0;
-
-        /* we do allocation within the reservation window if we have a window */
-        if (my_rsv) {
-                group_first_block = ext4_group_first_block_no(sb, group);
-                if (my_rsv->_rsv_start >= group_first_block)
-                        start = my_rsv->_rsv_start - group_first_block;
-                else
-                        /* reservation window cross group boundary */
-                        start = 0;
-                end = my_rsv->_rsv_end - group_first_block + 1;
-                if (end > EXT4_BLOCKS_PER_GROUP(sb))
-                        /* reservation window crosses group boundary */
-                        end = EXT4_BLOCKS_PER_GROUP(sb);
-                if ((start <= grp_goal) && (grp_goal < end))
-                        start = grp_goal;
-                else
-                        grp_goal = -1;
-        } else {
-                if (grp_goal > 0)
-                        start = grp_goal;
-                else
-                        start = 0;
-                end = EXT4_BLOCKS_PER_GROUP(sb);
-        }
-
-        BUG_ON(start > EXT4_BLOCKS_PER_GROUP(sb));
-
-repeat:
-        if (grp_goal < 0 || !ext4_test_allocatable(grp_goal, bitmap_bh)) {
-                grp_goal = find_next_usable_block(start, bitmap_bh, end);
-                if (grp_goal < 0)
-                        goto fail_access;
-                if (!my_rsv) {
-                        int i;
-
-                        for (i = 0; i < 7 && grp_goal > start &&
-                                        ext4_test_allocatable(grp_goal - 1,
-                                                                bitmap_bh);
-                                        i++, grp_goal--)
-                                ;
-                }
-        }
-        start = grp_goal;
-
-        if (!claim_block(sb_bgl_lock(EXT4_SB(sb), group),
-                grp_goal, bitmap_bh)) {
-                /*
-                 * The block was allocated by another thread, or it was
-                 * allocated and then freed by another thread
-                 */
-                start++;
-                grp_goal++;
-                if (start >= end)
-                        goto fail_access;
-                goto repeat;
-        }
-        num++;
-        grp_goal++;
-        while (num < *count && grp_goal < end
-                && ext4_test_allocatable(grp_goal, bitmap_bh)
-                && claim_block(sb_bgl_lock(EXT4_SB(sb), group),
-                                grp_goal, bitmap_bh)) {
-                num++;
-                grp_goal++;
-        }
-        *count = num;
-        return grp_goal - num;
-fail_access:
-        *count = num;
-        return -1;
-}
-
-/**
- *      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;
- *              This is not necessarily the list head of the whole filesystem
- *
- *              We have both head and start_block to assist the search
- *              for the reservable space. The list starts from head,
- *              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
- *
- *      @group_first_block: the first block we consider to start
- *                      the real search from
- *
- *      @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
- *              possible reservable space is out of this boundary.
- *              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.
- *
- */
-static int find_next_reservable_window(
-                                struct ext4_reserve_window_node *search_head,
-                                struct ext4_reserve_window_node *my_rsv,
-                                struct super_block * sb,
-                                ext4_fsblk_t start_block,
-                                ext4_fsblk_t last_block)
-{
-        struct rb_node *next;
-        struct ext4_reserve_window_node *rsv, *prev;
-        ext4_fsblk_t cur;
-        int size = my_rsv->rsv_goal_size;
-
-        /* TODO: make the start of the reservation window byte-aligned */
-        /* cur = *start_block & ~7;*/
-        cur = start_block;
-        rsv = search_head;
-        if (!rsv)
-                return -1;
-
-        while (1) {
-                if (cur <= rsv->rsv_end)
-                        cur = rsv->rsv_end + 1;
-
-                /* TODO?
-                 * in the case we could not find a reservable space
-                 * that is what is expected, during the re-search, we could
-                 * remember what's the largest reservable space we could have
-                 * and return that one.
-                 *
-                 * For now it will fail if we could not find the reservable
-                 * space with expected-size (or more)...
-                 */
-                if (cur > last_block)
-                        return -1;              /* fail */
-
-                prev = rsv;
-                next = rb_next(&rsv->rsv_node);
-                rsv = rb_entry(next,struct ext4_reserve_window_node,rsv_node);
+        if (!capable(CAP_SYS_RESOURCE) &&
+                sbi->s_resuid != current->fsuid &&
+                (sbi->s_resgid == 0 || !in_group_p(sbi->s_resgid)))
+                root_blocks = ext4_r_blocks_count(sbi->s_es);
 
-                /*
-                 * Reached the last reservation, we can just append to the
-                 * previous one.
-                 */
-                if (!next)
-                        break;
-
-                if (cur + size <= rsv->rsv_start) {
-                        /*
-                         * Found a reserveable space big enough.  We could
-                         * have a reservation across the group boundary here
-                         */
-                        break;
+        if (free_blocks - (nblocks + root_blocks + dirty_blocks) <
+                                                EXT4_FREEBLOCKS_WATERMARK) {
+                free_blocks  = percpu_counter_sum(fbc);
+                dirty_blocks = percpu_counter_sum(dbc);
+                if (dirty_blocks < 0) {
+                        printk(KERN_CRIT "Dirty block accounting "
+                                        "went wrong %lld\n",
+                                        dirty_blocks);
                 }
         }
-        /*
-         * we come here either :
-         * when we reach the end of the whole list,
-         * and there is empty reservable space after last entry in the list.
-         * append it to the end of the list.
-         *
-         * or we found one reservable space in the middle of the list,
-         * return the reservation window that we could append to.
-         * succeed.
+        /* Check whether we have space after
+         * accounting for current dirty blocks
          */
+        if (free_blocks < ((root_blocks + nblocks) + dirty_blocks))
+                /* we don't have free space */
+                return -ENOSPC;
 
-        if ((prev != my_rsv) && (!rsv_is_empty(&my_rsv->rsv_window)))
-                rsv_window_remove(sb, my_rsv);
-
-        /*
-         * Let's book the whole avaliable window for now.  We will check the
-         * disk bitmap later and then, if there are free blocks then we adjust
-         * the window size if it's larger than requested.
-         * Otherwise, we will remove this node from the tree next time
-         * call find_next_reservable_window.
-         */
-        my_rsv->rsv_start = cur;
-        my_rsv->rsv_end = cur + size - 1;
-        my_rsv->rsv_alloc_hit = 0;
-
-        if (prev != my_rsv)
-                ext4_rsv_window_add(sb, my_rsv);
-
+        /* Add the blocks to nblocks */
+        percpu_counter_add(dbc, nblocks);
         return 0;
 }
 
 /**
- *      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
- *              allocate a new reservation window near the allocation goal,
- *              or the beginning of the group, if there is no goal.
- *
- *              We first find a reservable space after the goal, then from
- *              there, we check the bitmap for the first free block after
- *              it. If there is no free block until the end of group, then the
- *              whole group is full, we failed. Otherwise, check if the free
- *              block is inside the expected reservable space, if so, we
- *              succeed.
- *              If the first free block is outside the reservable space, then
- *              start from the first free block, we search for next available
- *              space, and go on.
- *
- *      on succeed, a new reservation will be found and inserted into the list
- *      It contains at least one free block, and it does not overlap with other
- *      reservation windows.
- *
- *      failed: we failed to find a reservation window in this group
- *
- *      @rsv: the reservation
- *
- *      @grp_goal: The goal (group-relative).  It is where the search for a
- *              free reservable space should start from.
- *              if we have a grp_goal(grp_goal >0 ), then start from there,
- *              no grp_goal(grp_goal = -1), we start from the first block
- *              of the group.
- *
- *      @sb: the super block
- *      @group: the group we are trying to allocate in
- *      @bitmap_bh: the block group block bitmap
- *
- */
-static int alloc_new_reservation(struct ext4_reserve_window_node *my_rsv,
-                ext4_grpblk_t grp_goal, struct super_block *sb,
-                ext4_group_t group, struct buffer_head *bitmap_bh)
-{
-        struct ext4_reserve_window_node *search_head;
-        ext4_fsblk_t group_first_block, group_end_block, start_block;
-        ext4_grpblk_t first_free_block;
-        struct rb_root *fs_rsv_root = &EXT4_SB(sb)->s_rsv_window_root;
-        unsigned long size;
-        int ret;
-        spinlock_t *rsv_lock = &EXT4_SB(sb)->s_rsv_window_lock;
-
-        group_first_block = ext4_group_first_block_no(sb, group);
-        group_end_block = group_first_block + (EXT4_BLOCKS_PER_GROUP(sb) - 1);
-
-        if (grp_goal < 0)
-                start_block = group_first_block;
-        else
-                start_block = grp_goal + group_first_block;
-
-        size = my_rsv->rsv_goal_size;
-
-        if (!rsv_is_empty(&my_rsv->rsv_window)) {
-                /*
-                 * if the old reservation is cross group boundary
-                 * and if the goal is inside the old reservation window,
-                 * we will come here when we just failed to allocate from
-                 * the first part of the window. We still have another part
-                 * that belongs to the next group. In this case, there is no
-                 * point to discard our window and try to allocate a new one
-                 * in this group(which will fail). we should
-                 * keep the reservation window, just simply move on.
-                 *
-                 * Maybe we could shift the start block of the reservation
-                 * window to the first block of next group.
-                 */
-
-                if ((my_rsv->rsv_start <= group_end_block) &&
-                                (my_rsv->rsv_end > group_end_block) &&
-                                (start_block >= my_rsv->rsv_start))
-                        return -1;
-
-                if ((my_rsv->rsv_alloc_hit >
-                     (my_rsv->rsv_end - my_rsv->rsv_start + 1) / 2)) {
-                        /*
-                         * if the previously allocation hit ratio is
-                         * greater than 1/2, then we double the size of
-                         * the reservation window the next time,
-                         * otherwise we keep the same size window
-                         */
-                        size = size * 2;
-                        if (size > EXT4_MAX_RESERVE_BLOCKS)
-                                size = EXT4_MAX_RESERVE_BLOCKS;
-                        my_rsv->rsv_goal_size= size;
-                }
-        }
-
-        spin_lock(rsv_lock);
-        /*
-         * shift the search start to the window near the goal block
-         */
-        search_head = search_reserve_window(fs_rsv_root, start_block);
-
-        /*
-         * find_next_reservable_window() simply finds a reservable window
-         * inside the given range(start_block, group_end_block).
-         *
-         * To make sure the reservation window has a free bit inside it, we
-         * need to check the bitmap after we found a reservable window.
-         */
-retry:
-        ret = find_next_reservable_window(search_head, my_rsv, sb,
-                                                start_block, group_end_block);
-
-        if (ret == -1) {
-                if (!rsv_is_empty(&my_rsv->rsv_window))
-                        rsv_window_remove(sb, my_rsv);
-                spin_unlock(rsv_lock);
-                return -1;
-        }
-
-        /*
-         * On success, find_next_reservable_window() returns the
-         * reservation window where there is a reservable space after it.
-         * Before we reserve this reservable space, we need
-         * to make sure there is at least a free block inside this region.
-         *
-         * searching the first free bit on the block bitmap and copy of
-         * last committed bitmap alternatively, until we found a allocatable
-         * block. Search start from the start block of the reservable space
-         * we just found.
-         */
-        spin_unlock(rsv_lock);
-        first_free_block = bitmap_search_next_usable_block(
-                        my_rsv->rsv_start - group_first_block,
-                        bitmap_bh, group_end_block - group_first_block + 1);
-
-        if (first_free_block < 0) {
-                /*
-                 * no free block left on the bitmap, no point
-                 * to reserve the space. return failed.
-                 */
-                spin_lock(rsv_lock);
-                if (!rsv_is_empty(&my_rsv->rsv_window))
-                        rsv_window_remove(sb, my_rsv);
-                spin_unlock(rsv_lock);
-                return -1;              /* failed */
-        }
-
-        start_block = first_free_block + group_first_block;
-        /*
-         * 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)
-                return 0;               /* success */
-        /*
-         * if the first free bit we found is out of the reservable space
-         * continue search for next reservable space,
-         * start from where the free block is,
-         * we also shift the list head to where we stopped last time
-         */
-        search_head = my_rsv;
-        spin_lock(rsv_lock);
-        goto retry;
-}
-
-/**
- * try_to_extend_reservation()
- * @my_rsv:             given reservation window
- * @sb:                 super block
- * @size:               the delta to extend
- *
- * Attempt to expand the reservation window large enough to have
- * required number of free blocks
- *
- * Since ext4_try_to_allocate() will always allocate blocks within
- * the reservation window range, if the window size is too small,
- * multiple blocks allocation has to stop at the end of the reservation
- * window. To make this more efficient, given the total number of
- * blocks needed and the current size of the window, we try to
- * expand the reservation window size if necessary on a best-effort
- * basis before ext4_new_blocks() tries to allocate blocks,
- */
-static void try_to_extend_reservation(struct ext4_reserve_window_node *my_rsv,
-                        struct super_block *sb, int size)
-{
-        struct ext4_reserve_window_node *next_rsv;
-        struct rb_node *next;
-        spinlock_t *rsv_lock = &EXT4_SB(sb)->s_rsv_window_lock;
-
-        if (!spin_trylock(rsv_lock))
-                return;
-
-        next = rb_next(&my_rsv->rsv_node);
-
-        if (!next)
-                my_rsv->rsv_end += size;
-        else {
-                next_rsv = rb_entry(next, struct ext4_reserve_window_node, rsv_node);
-
-                if ((next_rsv->rsv_start - my_rsv->rsv_end - 1) >= size)
-                        my_rsv->rsv_end += size;
-                else
-                        my_rsv->rsv_end = next_rsv->rsv_start - 1;
-        }
-        spin_unlock(rsv_lock);
-}
-
-/**
- * ext4_try_to_allocate_with_rsv()
- * @sb:                 superblock
- * @handle:             handle to this transaction
- * @group:              given allocation block group
- * @bitmap_bh:          bufferhead holds the block bitmap
- * @grp_goal:           given target block within the group
- * @count:              target number of blocks to allocate
- * @my_rsv:             reservation window
- * @errp:               pointer to store the error code
- *
- * This is the main function used to allocate a new block and its reservation
- * window.
- *
- * Each time when a new block allocation is need, first try to allocate from
- * its own reservation.  If it does not have a reservation window, instead of
- * looking for a free bit on bitmap first, then look up the reservation list to
- * see if it is inside somebody else's reservation window, we try to allocate a
- * reservation window for it starting from the goal first. Then do the block
- * allocation within the reservation window.
- *
- * This will avoid keeping on searching the reservation list again and
- * again when somebody is looking for a free block (without
- * reservation), and there are lots of free blocks, but they are all
- * being reserved.
- *
- * We use a red-black tree for the per-filesystem reservation list.
- *
- */
-static ext4_grpblk_t
-ext4_try_to_allocate_with_rsv(struct super_block *sb, handle_t *handle,
-                        ext4_group_t group, struct buffer_head *bitmap_bh,
-                        ext4_grpblk_t grp_goal,
-                        struct ext4_reserve_window_node * my_rsv,
-                        unsigned long *count, int *errp)
-{
-        ext4_fsblk_t group_first_block, group_last_block;
-        ext4_grpblk_t ret = 0;
-        int fatal;
-        unsigned long num = *count;
-
-        *errp = 0;
-
-        /*
-         * Make sure we use undo access for the bitmap, because it is critical
-         * that we do the frozen_data COW on bitmap buffers in all cases even
-         * if the buffer is in BJ_Forget state in the committing transaction.
-         */
-        BUFFER_TRACE(bitmap_bh, "get undo access for new block");
-        fatal = ext4_journal_get_undo_access(handle, bitmap_bh);
-        if (fatal) {
-                *errp = fatal;
-                return -1;
-        }
-
-        /*
-         * we don't deal with reservation when
-         * filesystem is mounted without reservation
-         * or the file is not a regular file
-         * or last attempt to allocate a block with reservation turned on failed
-         */
-        if (my_rsv == NULL ) {
-                ret = ext4_try_to_allocate(sb, handle, group, bitmap_bh,
-                                                grp_goal, count, NULL);
-                goto out;
-        }
-        /*
-         * grp_goal is a group relative block number (if there is a goal)
-         * 0 <= grp_goal < EXT4_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 = ext4_group_first_block_no(sb, group);
-        group_last_block = group_first_block + (EXT4_BLOCKS_PER_GROUP(sb) - 1);
-
-        /*
-         * Basically we will allocate a new block from inode's reservation
-         * window.
-         *
-         * We need to allocate a new reservation window, if:
-         * a) inode does not have a reservation window; or
-         * b) last attempt to allocate a block from existing reservation
-         *    failed; or
-         * c) we come here with a goal and with a reservation window
-         *
-         * We do not need to allocate a new reservation window if we come here
-         * at the beginning with a goal and the goal is inside the window, or
-         * we don't have a goal but already have a reservation window.
-         * then we could go to allocate from the reservation window directly.
-         */
-        while (1) {
-                if (rsv_is_empty(&my_rsv->rsv_window) || (ret < 0) ||
-                        !goal_in_my_reservation(&my_rsv->rsv_window,
-                                                grp_goal, group, sb)) {
-                        if (my_rsv->rsv_goal_size < *count)
-                                my_rsv->rsv_goal_size = *count;
-                        ret = alloc_new_reservation(my_rsv, grp_goal, sb,
-                                                        group, bitmap_bh);
-                        if (ret < 0)
-                                break;                  /* failed */
-
-                        if (!goal_in_my_reservation(&my_rsv->rsv_window,
-                                                        grp_goal, group, sb))
-                                grp_goal = -1;
-                } 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(&EXT4_SB(sb)->s_rsv_window_root, 1);
-                        BUG();
-                }
-                ret = ext4_try_to_allocate(sb, handle, group, bitmap_bh,
-                                           grp_goal, &num, &my_rsv->rsv_window);
-                if (ret >= 0) {
-                        my_rsv->rsv_alloc_hit += num;
-                        *count = num;
-                        break;                          /* succeed */
-                }
-                num = *count;
-        }
-out:
-        if (ret >= 0) {
-                BUFFER_TRACE(bitmap_bh, "journal_dirty_metadata for "
-                                        "bitmap block");
-                fatal = ext4_journal_dirty_metadata(handle, bitmap_bh);
-                if (fatal) {
-                        *errp = fatal;
-                        return -1;
-                }
-                return ret;
-        }
-
-        BUFFER_TRACE(bitmap_bh, "journal_release_buffer");
-        ext4_journal_release_buffer(handle, bitmap_bh);
-        return ret;
-}
-
-/**
  * ext4_has_free_blocks()
  * @sbi:        in-core super block structure.
  * @nblocks:    number of neeed blocks
@@ -1610,29 +637,34 @@ out:
  * On success, return nblocks
  */
 ext4_fsblk_t ext4_has_free_blocks(struct ext4_sb_info *sbi,
-                                                ext4_fsblk_t nblocks)
+                                                s64 nblocks)
 {
-        ext4_fsblk_t free_blocks;
-        ext4_fsblk_t root_blocks = 0;
+        s64 free_blocks, dirty_blocks;
+        s64 root_blocks = 0;
+        struct percpu_counter *fbc = &sbi->s_freeblocks_counter;
+        struct percpu_counter *dbc = &sbi->s_dirtyblocks_counter;
 
-        free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
+        free_blocks  = percpu_counter_read_positive(fbc);
+        dirty_blocks = percpu_counter_read_positive(dbc);
 
         if (!capable(CAP_SYS_RESOURCE) &&
                 sbi->s_resuid != current->fsuid &&
                 (sbi->s_resgid == 0 || !in_group_p(sbi->s_resgid)))
                 root_blocks = ext4_r_blocks_count(sbi->s_es);
-#ifdef CONFIG_SMP
-        if (free_blocks - root_blocks < FBC_BATCH)
-                free_blocks =
-                        percpu_counter_sum_and_set(&sbi->s_freeblocks_counter);
-#endif
-        if (free_blocks <= root_blocks)
+
+        if (free_blocks - (nblocks + root_blocks + dirty_blocks) <
+                                                EXT4_FREEBLOCKS_WATERMARK) {
+                free_blocks  = percpu_counter_sum(fbc);
+                dirty_blocks = percpu_counter_sum(dbc);
+        }
+        if (free_blocks <= (root_blocks + dirty_blocks))
                 /* we don't have free space */
                 return 0;
-        if (free_blocks - root_blocks < nblocks)
-                return free_blocks - root_blocks;
+
+        if (free_blocks - (root_blocks + dirty_blocks) < nblocks)
+                return free_blocks - (root_blocks + dirty_blocks);
         return nblocks;
- }
+}
 
 
 /**
@@ -1657,303 +689,6 @@ int ext4_should_retry_alloc(struct super_block *sb, int *retries)
         return jbd2_journal_force_commit_nested(EXT4_SB(sb)->s_journal);
 }
 
-/**
- * ext4_old_new_blocks() -- core block bitmap based block allocation function
- *
- * @handle:             handle to this transaction
- * @inode:              file inode
- * @goal:               given target block(filesystem wide)
- * @count:              target number of blocks to allocate
- * @errp:               error code
- *
- * ext4_old_new_blocks uses a goal block to assist allocation and look up
- * the block bitmap directly to do block allocation.  It tries to
- * allocate block(s) from the block group contains the goal block first. If
- * that fails, it will try to allocate block(s) from other block groups
- * without any specific goal block.
- *
- * This function is called when -o nomballoc mount option is enabled
- *
- */
-ext4_fsblk_t ext4_old_new_blocks(handle_t *handle, struct inode *inode,
-                        ext4_fsblk_t goal, unsigned long *count, int *errp)
-{
-        struct buffer_head *bitmap_bh = NULL;
-        struct buffer_head *gdp_bh;
-        ext4_group_t group_no;
-        ext4_group_t goal_group;
-        ext4_grpblk_t grp_target_blk;   /* blockgroup relative goal block */
-        ext4_grpblk_t grp_alloc_blk;    /* blockgroup-relative allocated block*/
-        ext4_fsblk_t ret_block;         /* filesyetem-wide allocated block */
-        ext4_group_t bgi;                       /* blockgroup iteration index */
-        int fatal = 0, err;
-        int performed_allocation = 0;
-        ext4_grpblk_t free_blocks;      /* number of free blocks in a group */
-        struct super_block *sb;
-        struct ext4_group_desc *gdp;
-        struct ext4_super_block *es;
-        struct ext4_sb_info *sbi;
-        struct ext4_reserve_window_node *my_rsv = NULL;
-        struct ext4_block_alloc_info *block_i;
-        unsigned short windowsz = 0;
-        ext4_group_t ngroups;
-        unsigned long num = *count;
-
-        sb = inode->i_sb;
-        if (!sb) {
-                *errp = -ENODEV;
-                printk("ext4_new_block: nonexistent device");
-                return 0;
-        }
-
-        sbi = EXT4_SB(sb);
-        if (!EXT4_I(inode)->i_delalloc_reserved_flag) {
-                /*
-                 * With delalloc we already reserved the blocks
-                 */
-                *count = ext4_has_free_blocks(sbi, *count);
-        }
-        if (*count == 0) {
-                *errp = -ENOSPC;
-                return 0;       /*return with ENOSPC error */
-        }
-        num = *count;
-
-        /*
-         * Check quota for allocation of this block.
-         */
-        if (DQUOT_ALLOC_BLOCK(inode, num)) {
-                *errp = -EDQUOT;
-                return 0;
-        }
-
-        sbi = EXT4_SB(sb);
-        es = EXT4_SB(sb)->s_es;
-        ext4_debug("goal=%llu.\n", goal);
-        /*
-         * Allocate a block from reservation only when
-         * filesystem is mounted with reservation(default,-o reservation), and
-         * it's a regular file, and
-         * the desired window size is greater than 0 (One could use ioctl
-         * command EXT4_IOC_SETRSVSZ to set the window size to 0 to turn off
-         * reservation on that particular file)
-         */
-        block_i = EXT4_I(inode)->i_block_alloc_info;
-        if (block_i && ((windowsz = block_i->rsv_window_node.rsv_goal_size) > 0))
-                my_rsv = &block_i->rsv_window_node;
-
-        /*
-         * First, test whether the goal block is free.
-         */
-        if (goal < le32_to_cpu(es->s_first_data_block) ||
-            goal >= ext4_blocks_count(es))
-                goal = le32_to_cpu(es->s_first_data_block);
-        ext4_get_group_no_and_offset(sb, goal, &group_no, &grp_target_blk);
-        goal_group = group_no;
-retry_alloc:
-        gdp = ext4_get_group_desc(sb, group_no, &gdp_bh);
-        if (!gdp)
-                goto io_error;
-
-        free_blocks = le16_to_cpu(gdp->bg_free_blocks_count);
-        /*
-         * if there is not enough free blocks to make a new resevation
-         * turn off reservation for this allocation
-         */
-        if (my_rsv && (free_blocks < windowsz)
-                && (rsv_is_empty(&my_rsv->rsv_window)))
-                my_rsv = NULL;
-
-        if (free_blocks > 0) {
-                bitmap_bh = ext4_read_block_bitmap(sb, group_no);
-                if (!bitmap_bh)
-                        goto io_error;
-                grp_alloc_blk = ext4_try_to_allocate_with_rsv(sb, handle,
-                                        group_no, bitmap_bh, grp_target_blk,
-                                        my_rsv, &num, &fatal);
-                if (fatal)
-                        goto out;
-                if (grp_alloc_blk >= 0)
-                        goto allocated;
-        }
-
-        ngroups = EXT4_SB(sb)->s_groups_count;
-        smp_rmb();
-
-        /*
-         * Now search the rest of the groups.  We assume that
-         * 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 = ext4_get_group_desc(sb, group_no, &gdp_bh);
-                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))
-                        continue;
-
-                brelse(bitmap_bh);
-                bitmap_bh = ext4_read_block_bitmap(sb, group_no);
-                if (!bitmap_bh)
-                        goto io_error;
-                /*
-                 * try to allocate block(s) from this group, without a goal(-1).
-                 */
-                grp_alloc_blk = ext4_try_to_allocate_with_rsv(sb, handle,
-                                        group_no, bitmap_bh, -1, my_rsv,
-                                        &num, &fatal);
-                if (fatal)
-                        goto out;
-                if (grp_alloc_blk >= 0)
-                        goto allocated;
-        }
-        /*
-         * We may end up a bogus ealier ENOSPC error due to
-         * filesystem is "full" of reservations, but
-         * there maybe indeed free blocks avaliable on disk
-         * In this case, we just forget about the reservations
-         * just do block allocation as without reservations.
-         */
-        if (my_rsv) {
-                my_rsv = NULL;
-                windowsz = 0;
-                group_no = goal_group;
-                goto retry_alloc;
-        }
-        /* No space left on the device */
-        *errp = -ENOSPC;
-        goto out;
-
-allocated:
-
-        ext4_debug("using block group %lu(%d)\n",
-                        group_no, gdp->bg_free_blocks_count);
-
-        BUFFER_TRACE(gdp_bh, "get_write_access");
-        fatal = ext4_journal_get_write_access(handle, gdp_bh);
-        if (fatal)
-                goto out;
-
-        ret_block = grp_alloc_blk + ext4_group_first_block_no(sb, group_no);
-
-        if (in_range(ext4_block_bitmap(sb, gdp), ret_block, num) ||
-            in_range(ext4_inode_bitmap(sb, gdp), ret_block, num) ||
-            in_range(ret_block, ext4_inode_table(sb, gdp),
-                     EXT4_SB(sb)->s_itb_per_group) ||
-            in_range(ret_block + num - 1, ext4_inode_table(sb, gdp),
-                     EXT4_SB(sb)->s_itb_per_group)) {
-                ext4_error(sb, "ext4_new_block",
-                            "Allocating block in system zone - "
-                            "blocks from %llu, 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;
-
-#ifdef CONFIG_JBD2_DEBUG
-        {
-                struct buffer_head *debug_bh;
-
-                /* Record bitmap buffer state in the newly allocated block */
-                debug_bh = sb_find_get_block(sb, ret_block);
-                if (debug_bh) {
-                        BUFFER_TRACE(debug_bh, "state when allocated");
-                        BUFFER_TRACE2(debug_bh, bitmap_bh, "bitmap state");
-                        brelse(debug_bh);
-                }
-        }
-        jbd_lock_bh_state(bitmap_bh);
-        spin_lock(sb_bgl_lock(sbi, group_no));
-        if (buffer_jbd(bitmap_bh) && bh2jh(bitmap_bh)->b_committed_data) {
-                int i;
-
-                for (i = 0; i < num; i++) {
-                        if (ext4_test_bit(grp_alloc_blk+i,
-                                        bh2jh(bitmap_bh)->b_committed_data)) {
-                                printk("%s: block was unexpectedly set in "
-                                        "b_committed_data\n", __func__);
-                        }
-                }
-        }
-        ext4_debug("found bit %d\n", grp_alloc_blk);
-        spin_unlock(sb_bgl_lock(sbi, group_no));
-        jbd_unlock_bh_state(bitmap_bh);
-#endif
-
-        if (ret_block + num - 1 >= ext4_blocks_count(es)) {
-                ext4_error(sb, "ext4_new_block",
-                            "block(%llu) >= blocks count(%llu) - "
-                            "block_group = %lu, es == %p ", ret_block,
-                        ext4_blocks_count(es), group_no, es);
-                goto out;
-        }
-
-        /*
-         * It is up to the caller to add the new buffer to a journal
-         * list of some description.  We don't know in advance whether
-         * the caller wants to use it as metadata or data.
-         */
-        spin_lock(sb_bgl_lock(sbi, group_no));
-        if (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT))
-                gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT);
-        le16_add_cpu(&gdp->bg_free_blocks_count, -num);
-        gdp->bg_checksum = ext4_group_desc_csum(sbi, group_no, gdp);
-        spin_unlock(sb_bgl_lock(sbi, group_no));
-        if (!EXT4_I(inode)->i_delalloc_reserved_flag)
-                percpu_counter_sub(&sbi->s_freeblocks_counter, num);
-
-        if (sbi->s_log_groups_per_flex) {
-                ext4_group_t flex_group = ext4_flex_group(sbi, group_no);
-                spin_lock(sb_bgl_lock(sbi, flex_group));
-                sbi->s_flex_groups[flex_group].free_blocks -= num;
-                spin_unlock(sb_bgl_lock(sbi, flex_group));
-        }
-
-        BUFFER_TRACE(gdp_bh, "journal_dirty_metadata for group descriptor");
-        err = ext4_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);
-        *count = num;
-        return ret_block;
-
-io_error:
-        *errp = -EIO;
-out:
-        if (fatal) {
-                *errp = fatal;
-                ext4_std_error(sb, fatal);
-        }
-        /*
-         * Undo the block allocation
-         */
-        if (!performed_allocation)
-                DQUOT_FREE_BLOCK(inode, *count);
-        brelse(bitmap_bh);
-        return 0;
-}
-
 #define EXT4_META_BLOCK 0x1
 
 static ext4_fsblk_t do_blk_alloc(handle_t *handle, struct inode *inode,
@@ -1963,10 +698,6 @@ static ext4_fsblk_t do_blk_alloc(handle_t *handle, struct inode *inode,
         struct ext4_allocation_request ar;
         ext4_fsblk_t ret;
 
-        if (!test_opt(inode->i_sb, MBALLOC)) {
-                return ext4_old_new_blocks(handle, inode, goal, count, errp);
-        }
-
         memset(&ar, 0, sizeof(ar));
         /* Fill with neighbour allocated blocks */
 
@@ -2008,7 +739,7 @@ ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
         /*
          * Account for the allocated meta blocks
          */
-        if (!(*errp)) {
+        if (!(*errp) && EXT4_I(inode)->i_delalloc_reserved_flag) {
                 spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
                 EXT4_I(inode)->i_allocated_meta_blocks += *count;
                 spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
@@ -2093,10 +824,9 @@ ext4_fsblk_t ext4_count_free_blocks(struct super_block *sb)
                 bitmap_count += x;
         }
         brelse(bitmap_bh);
-        printk("ext4_count_free_blocks: stored = %llu"
-                ", computed = %llu, %llu\n",
-                ext4_free_blocks_count(es),
-                desc_count, bitmap_count);
+        printk(KERN_DEBUG "ext4_count_free_blocks: stored = %llu"
+                ", computed = %llu, %llu\n", ext4_free_blocks_count(es),
+               desc_count, bitmap_count);
         return bitmap_count;
 #else
         desc_count = 0;
@@ -2183,8 +913,9 @@ unsigned long ext4_bg_num_gdb(struct super_block *sb, ext4_group_t group)
 
         if (!EXT4_HAS_INCOMPAT_FEATURE(sb,EXT4_FEATURE_INCOMPAT_META_BG) ||
                         metagroup < first_meta_bg)
-                return ext4_bg_num_gdb_nometa(sb,group);
+                return ext4_bg_num_gdb_nometa(sb, group);
 
         return ext4_bg_num_gdb_meta(sb,group);
 
 }
+