reiserfs: Don't call reiserfs_get_acl() with the reiserfs lock
[safe/jmp/linux-2.6] / fs / btrfs / inode.c
index db9cbd9..b3ad168 100644 (file)
@@ -55,14 +55,14 @@ struct btrfs_iget_args {
        struct btrfs_root *root;
 };
 
-static struct inode_operations btrfs_dir_inode_operations;
-static struct inode_operations btrfs_symlink_inode_operations;
-static struct inode_operations btrfs_dir_ro_inode_operations;
-static struct inode_operations btrfs_special_inode_operations;
-static struct inode_operations btrfs_file_inode_operations;
-static struct address_space_operations btrfs_aops;
-static struct address_space_operations btrfs_symlink_aops;
-static struct file_operations btrfs_dir_file_operations;
+static const struct inode_operations btrfs_dir_inode_operations;
+static const struct inode_operations btrfs_symlink_inode_operations;
+static const struct inode_operations btrfs_dir_ro_inode_operations;
+static const struct inode_operations btrfs_special_inode_operations;
+static const struct inode_operations btrfs_file_inode_operations;
+static const struct address_space_operations btrfs_aops;
+static const struct address_space_operations btrfs_symlink_aops;
+static const struct file_operations btrfs_dir_file_operations;
 static struct extent_io_ops btrfs_extent_io_ops;
 
 static struct kmem_cache *btrfs_inode_cachep;
@@ -424,9 +424,12 @@ again:
                         * and free up our temp pages.
                         */
                        extent_clear_unlock_delalloc(inode,
-                                                    &BTRFS_I(inode)->io_tree,
-                                                    start, end, NULL, 1, 0,
-                                                    0, 1, 1, 1, 0);
+                            &BTRFS_I(inode)->io_tree,
+                            start, end, NULL,
+                            EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_DIRTY |
+                            EXTENT_CLEAR_DELALLOC |
+                            EXTENT_CLEAR_ACCOUNTING |
+                            EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK);
                        ret = 0;
                        goto free_pages_out;
                }
@@ -535,7 +538,7 @@ static noinline int submit_compressed_extents(struct inode *inode,
        struct btrfs_root *root = BTRFS_I(inode)->root;
        struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
        struct extent_io_tree *io_tree;
-       int ret;
+       int ret = 0;
 
        if (list_empty(&async_cow->extents))
                return 0;
@@ -549,6 +552,7 @@ static noinline int submit_compressed_extents(struct inode *inode,
 
                io_tree = &BTRFS_I(inode)->io_tree;
 
+retry:
                /* did the compression code fall back to uncompressed IO? */
                if (!async_extent->pages) {
                        int page_started = 0;
@@ -559,11 +563,11 @@ static noinline int submit_compressed_extents(struct inode *inode,
                                    async_extent->ram_size - 1, GFP_NOFS);
 
                        /* allocate blocks */
-                       cow_file_range(inode, async_cow->locked_page,
-                                      async_extent->start,
-                                      async_extent->start +
-                                      async_extent->ram_size - 1,
-                                      &page_started, &nr_written, 0);
+                       ret = cow_file_range(inode, async_cow->locked_page,
+                                            async_extent->start,
+                                            async_extent->start +
+                                            async_extent->ram_size - 1,
+                                            &page_started, &nr_written, 0);
 
                        /*
                         * if page_started, cow_file_range inserted an
@@ -571,7 +575,7 @@ static noinline int submit_compressed_extents(struct inode *inode,
                         * and IO for us.  Otherwise, we need to submit
                         * all those pages down to the drive.
                         */
-                       if (!page_started)
+                       if (!page_started && !ret)
                                extent_write_locked_range(io_tree,
                                                  inode, async_extent->start,
                                                  async_extent->start +
@@ -599,7 +603,21 @@ static noinline int submit_compressed_extents(struct inode *inode,
                                           async_extent->compressed_size,
                                           0, alloc_hint,
                                           (u64)-1, &ins, 1);
-               BUG_ON(ret);
+               if (ret) {
+                       int i;
+                       for (i = 0; i < async_extent->nr_pages; i++) {
+                               WARN_ON(async_extent->pages[i]->mapping);
+                               page_cache_release(async_extent->pages[i]);
+                       }
+                       kfree(async_extent->pages);
+                       async_extent->nr_pages = 0;
+                       async_extent->pages = NULL;
+                       unlock_extent(io_tree, async_extent->start,
+                                     async_extent->start +
+                                     async_extent->ram_size - 1, GFP_NOFS);
+                       goto retry;
+               }
+
                em = alloc_extent_map(GFP_NOFS);
                em->start = async_extent->start;
                em->len = async_extent->ram_size;
@@ -637,11 +655,14 @@ static noinline int submit_compressed_extents(struct inode *inode,
                 * clear dirty, set writeback and unlock the pages.
                 */
                extent_clear_unlock_delalloc(inode,
-                                            &BTRFS_I(inode)->io_tree,
-                                            async_extent->start,
-                                            async_extent->start +
-                                            async_extent->ram_size - 1,
-                                            NULL, 1, 1, 0, 1, 1, 0, 0);
+                               &BTRFS_I(inode)->io_tree,
+                               async_extent->start,
+                               async_extent->start +
+                               async_extent->ram_size - 1,
+                               NULL, EXTENT_CLEAR_UNLOCK_PAGE |
+                               EXTENT_CLEAR_UNLOCK |
+                               EXTENT_CLEAR_DELALLOC |
+                               EXTENT_CLEAR_DIRTY | EXTENT_SET_WRITEBACK);
 
                ret = btrfs_submit_compressed_write(inode,
                                    async_extent->start,
@@ -712,9 +733,15 @@ static noinline int cow_file_range(struct inode *inode,
                                            start, end, 0, NULL);
                if (ret == 0) {
                        extent_clear_unlock_delalloc(inode,
-                                                    &BTRFS_I(inode)->io_tree,
-                                                    start, end, NULL, 1, 1,
-                                                    1, 1, 1, 1, 0);
+                                    &BTRFS_I(inode)->io_tree,
+                                    start, end, NULL,
+                                    EXTENT_CLEAR_UNLOCK_PAGE |
+                                    EXTENT_CLEAR_UNLOCK |
+                                    EXTENT_CLEAR_DELALLOC |
+                                    EXTENT_CLEAR_ACCOUNTING |
+                                    EXTENT_CLEAR_DIRTY |
+                                    EXTENT_SET_WRITEBACK |
+                                    EXTENT_END_WRITEBACK);
                        *nr_written = *nr_written +
                             (end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE;
                        *page_started = 1;
@@ -731,13 +758,29 @@ static noinline int cow_file_range(struct inode *inode,
        em = search_extent_mapping(&BTRFS_I(inode)->extent_tree,
                                   start, num_bytes);
        if (em) {
-               alloc_hint = em->block_start;
-               free_extent_map(em);
+               /*
+                * if block start isn't an actual block number then find the
+                * first block in this inode and use that as a hint.  If that
+                * block is also bogus then just don't worry about it.
+                */
+               if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
+                       free_extent_map(em);
+                       em = search_extent_mapping(em_tree, 0, 0);
+                       if (em && em->block_start < EXTENT_MAP_LAST_BYTE)
+                               alloc_hint = em->block_start;
+                       if (em)
+                               free_extent_map(em);
+               } else {
+                       alloc_hint = em->block_start;
+                       free_extent_map(em);
+               }
        }
        read_unlock(&BTRFS_I(inode)->extent_tree.lock);
        btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0);
 
        while (disk_num_bytes > 0) {
+               unsigned long op;
+
                cur_alloc_size = min(disk_num_bytes, root->fs_info->max_extent);
                ret = btrfs_reserve_extent(trans, root, cur_alloc_size,
                                           root->sectorsize, 0, alloc_hint,
@@ -789,10 +832,13 @@ static noinline int cow_file_range(struct inode *inode,
                 * Do set the Private2 bit so we know this page was properly
                 * setup for writepage
                 */
+               op = unlock ? EXTENT_CLEAR_UNLOCK_PAGE : 0;
+               op |= EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
+                       EXTENT_SET_PRIVATE2;
+
                extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
                                             start, start + ram_size - 1,
-                                            locked_page, unlock, 1,
-                                            1, 0, 0, 0, 1);
+                                            locked_page, op);
                disk_num_bytes -= cur_alloc_size;
                num_bytes -= cur_alloc_size;
                alloc_hint = ins.objectid + ins.offset;
@@ -864,8 +910,8 @@ static int cow_file_range_async(struct inode *inode, struct page *locked_page,
        u64 cur_end;
        int limit = 10 * 1024 * 1042;
 
-       clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED |
-                        EXTENT_DELALLOC, 1, 0, NULL, GFP_NOFS);
+       clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED,
+                        1, 0, NULL, GFP_NOFS);
        while (start < end) {
                async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS);
                async_cow->inode = inode;
@@ -1006,6 +1052,7 @@ next_slot:
 
                if (found_key.offset > cur_offset) {
                        extent_end = found_key.offset;
+                       extent_type = 0;
                        goto out_check;
                }
 
@@ -1112,8 +1159,10 @@ out_check:
                BUG_ON(ret);
 
                extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
-                                       cur_offset, cur_offset + num_bytes - 1,
-                                       locked_page, 1, 1, 1, 0, 0, 0, 1);
+                               cur_offset, cur_offset + num_bytes - 1,
+                               locked_page, EXTENT_CLEAR_UNLOCK_PAGE |
+                               EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
+                               EXTENT_SET_PRIVATE2);
                cur_offset = extent_end;
                if (cur_offset > end)
                        break;
@@ -1159,6 +1208,89 @@ static int run_delalloc_range(struct inode *inode, struct page *locked_page,
        return ret;
 }
 
+static int btrfs_split_extent_hook(struct inode *inode,
+                                   struct extent_state *orig, u64 split)
+{
+       struct btrfs_root *root = BTRFS_I(inode)->root;
+       u64 size;
+
+       if (!(orig->state & EXTENT_DELALLOC))
+               return 0;
+
+       size = orig->end - orig->start + 1;
+       if (size > root->fs_info->max_extent) {
+               u64 num_extents;
+               u64 new_size;
+
+               new_size = orig->end - split + 1;
+               num_extents = div64_u64(size + root->fs_info->max_extent - 1,
+                                       root->fs_info->max_extent);
+
+               /*
+                * if we break a large extent up then leave oustanding_extents
+                * be, since we've already accounted for the large extent.
+                */
+               if (div64_u64(new_size + root->fs_info->max_extent - 1,
+                             root->fs_info->max_extent) < num_extents)
+                       return 0;
+       }
+
+       spin_lock(&BTRFS_I(inode)->accounting_lock);
+       BTRFS_I(inode)->outstanding_extents++;
+       spin_unlock(&BTRFS_I(inode)->accounting_lock);
+
+       return 0;
+}
+
+/*
+ * extent_io.c merge_extent_hook, used to track merged delayed allocation
+ * extents so we can keep track of new extents that are just merged onto old
+ * extents, such as when we are doing sequential writes, so we can properly
+ * account for the metadata space we'll need.
+ */
+static int btrfs_merge_extent_hook(struct inode *inode,
+                                  struct extent_state *new,
+                                  struct extent_state *other)
+{
+       struct btrfs_root *root = BTRFS_I(inode)->root;
+       u64 new_size, old_size;
+       u64 num_extents;
+
+       /* not delalloc, ignore it */
+       if (!(other->state & EXTENT_DELALLOC))
+               return 0;
+
+       old_size = other->end - other->start + 1;
+       if (new->start < other->start)
+               new_size = other->end - new->start + 1;
+       else
+               new_size = new->end - other->start + 1;
+
+       /* we're not bigger than the max, unreserve the space and go */
+       if (new_size <= root->fs_info->max_extent) {
+               spin_lock(&BTRFS_I(inode)->accounting_lock);
+               BTRFS_I(inode)->outstanding_extents--;
+               spin_unlock(&BTRFS_I(inode)->accounting_lock);
+               return 0;
+       }
+
+       /*
+        * If we grew by another max_extent, just return, we want to keep that
+        * reserved amount.
+        */
+       num_extents = div64_u64(old_size + root->fs_info->max_extent - 1,
+                               root->fs_info->max_extent);
+       if (div64_u64(new_size + root->fs_info->max_extent - 1,
+                     root->fs_info->max_extent) > num_extents)
+               return 0;
+
+       spin_lock(&BTRFS_I(inode)->accounting_lock);
+       BTRFS_I(inode)->outstanding_extents--;
+       spin_unlock(&BTRFS_I(inode)->accounting_lock);
+
+       return 0;
+}
+
 /*
  * extent_io.c set_bit_hook, used to track delayed allocation
  * bytes in this file, and to maintain the list of inodes that
@@ -1167,6 +1299,7 @@ static int run_delalloc_range(struct inode *inode, struct page *locked_page,
 static int btrfs_set_bit_hook(struct inode *inode, u64 start, u64 end,
                       unsigned long old, unsigned long bits)
 {
+
        /*
         * set_bit and clear bit hooks normally require _irqsave/restore
         * but in this case, we are only testeing for the DELALLOC
@@ -1174,6 +1307,10 @@ static int btrfs_set_bit_hook(struct inode *inode, u64 start, u64 end,
         */
        if (!(old & EXTENT_DELALLOC) && (bits & EXTENT_DELALLOC)) {
                struct btrfs_root *root = BTRFS_I(inode)->root;
+
+               spin_lock(&BTRFS_I(inode)->accounting_lock);
+               BTRFS_I(inode)->outstanding_extents++;
+               spin_unlock(&BTRFS_I(inode)->accounting_lock);
                btrfs_delalloc_reserve_space(root, inode, end - start + 1);
                spin_lock(&root->fs_info->delalloc_lock);
                BTRFS_I(inode)->delalloc_bytes += end - start + 1;
@@ -1190,22 +1327,31 @@ static int btrfs_set_bit_hook(struct inode *inode, u64 start, u64 end,
 /*
  * extent_io.c clear_bit_hook, see set_bit_hook for why
  */
-static int btrfs_clear_bit_hook(struct inode *inode, u64 start, u64 end,
-                        unsigned long old, unsigned long bits)
+static int btrfs_clear_bit_hook(struct inode *inode,
+                               struct extent_state *state, unsigned long bits)
 {
        /*
         * set_bit and clear bit hooks normally require _irqsave/restore
         * but in this case, we are only testeing for the DELALLOC
         * bit, which is only set or cleared with irqs on
         */
-       if ((old & EXTENT_DELALLOC) && (bits & EXTENT_DELALLOC)) {
+       if ((state->state & EXTENT_DELALLOC) && (bits & EXTENT_DELALLOC)) {
                struct btrfs_root *root = BTRFS_I(inode)->root;
 
+               if (bits & EXTENT_DO_ACCOUNTING) {
+                       spin_lock(&BTRFS_I(inode)->accounting_lock);
+                       BTRFS_I(inode)->outstanding_extents--;
+                       spin_unlock(&BTRFS_I(inode)->accounting_lock);
+                       btrfs_unreserve_metadata_for_delalloc(root, inode, 1);
+               }
+
                spin_lock(&root->fs_info->delalloc_lock);
-               if (end - start + 1 > root->fs_info->delalloc_bytes) {
+               if (state->end - state->start + 1 >
+                   root->fs_info->delalloc_bytes) {
                        printk(KERN_INFO "btrfs warning: delalloc account "
                               "%llu %llu\n",
-                              (unsigned long long)end - start + 1,
+                              (unsigned long long)
+                              state->end - state->start + 1,
                               (unsigned long long)
                               root->fs_info->delalloc_bytes);
                        btrfs_delalloc_free_space(root, inode, (u64)-1);
@@ -1213,9 +1359,12 @@ static int btrfs_clear_bit_hook(struct inode *inode, u64 start, u64 end,
                        BTRFS_I(inode)->delalloc_bytes = 0;
                } else {
                        btrfs_delalloc_free_space(root, inode,
-                                                 end - start + 1);
-                       root->fs_info->delalloc_bytes -= end - start + 1;
-                       BTRFS_I(inode)->delalloc_bytes -= end - start + 1;
+                                                 state->end -
+                                                 state->start + 1);
+                       root->fs_info->delalloc_bytes -= state->end -
+                               state->start + 1;
+                       BTRFS_I(inode)->delalloc_bytes -= state->end -
+                               state->start + 1;
                }
                if (BTRFS_I(inode)->delalloc_bytes == 0 &&
                    !list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
@@ -2354,7 +2503,19 @@ static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
 
        root = BTRFS_I(dir)->root;
 
+       /*
+        * 5 items for unlink inode
+        * 1 for orphan
+        */
+       ret = btrfs_reserve_metadata_space(root, 6);
+       if (ret)
+               return ret;
+
        trans = btrfs_start_transaction(root, 1);
+       if (IS_ERR(trans)) {
+               btrfs_unreserve_metadata_space(root, 6);
+               return PTR_ERR(trans);
+       }
 
        btrfs_set_trans_block_group(trans, dir);
 
@@ -2369,6 +2530,7 @@ static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
        nr = trans->blocks_used;
 
        btrfs_end_transaction_throttle(trans, root);
+       btrfs_unreserve_metadata_space(root, 6);
        btrfs_btree_balance_dirty(root, nr);
        return ret;
 }
@@ -2449,7 +2611,16 @@ static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
            inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)
                return -ENOTEMPTY;
 
+       ret = btrfs_reserve_metadata_space(root, 5);
+       if (ret)
+               return ret;
+
        trans = btrfs_start_transaction(root, 1);
+       if (IS_ERR(trans)) {
+               btrfs_unreserve_metadata_space(root, 5);
+               return PTR_ERR(trans);
+       }
+
        btrfs_set_trans_block_group(trans, dir);
 
        if (unlikely(inode->i_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
@@ -2472,6 +2643,7 @@ static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
 out:
        nr = trans->blocks_used;
        ret = btrfs_end_transaction_throttle(trans, root);
+       btrfs_unreserve_metadata_space(root, 5);
        btrfs_btree_balance_dirty(root, nr);
 
        if (ret && !err)
@@ -2912,12 +3084,22 @@ static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
 
        if ((offset & (blocksize - 1)) == 0)
                goto out;
+       ret = btrfs_check_data_free_space(root, inode, PAGE_CACHE_SIZE);
+       if (ret)
+               goto out;
+
+       ret = btrfs_reserve_metadata_for_delalloc(root, inode, 1);
+       if (ret)
+               goto out;
 
        ret = -ENOMEM;
 again:
        page = grab_cache_page(mapping, index);
-       if (!page)
+       if (!page) {
+               btrfs_free_reserved_data_space(root, inode, PAGE_CACHE_SIZE);
+               btrfs_unreserve_metadata_for_delalloc(root, inode, 1);
                goto out;
+       }
 
        page_start = page_offset(page);
        page_end = page_start + PAGE_CACHE_SIZE - 1;
@@ -2950,7 +3132,16 @@ again:
                goto again;
        }
 
-       btrfs_set_extent_delalloc(inode, page_start, page_end);
+       clear_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end,
+                         EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING,
+                         GFP_NOFS);
+
+       ret = btrfs_set_extent_delalloc(inode, page_start, page_end);
+       if (ret) {
+               unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
+               goto out_unlock;
+       }
+
        ret = 0;
        if (offset != PAGE_CACHE_SIZE) {
                kaddr = kmap(page);
@@ -2963,6 +3154,9 @@ again:
        unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
 
 out_unlock:
+       if (ret)
+               btrfs_free_reserved_data_space(root, inode, PAGE_CACHE_SIZE);
+       btrfs_unreserve_metadata_for_delalloc(root, inode, 1);
        unlock_page(page);
        page_cache_release(page);
 out:
@@ -2981,17 +3175,15 @@ int btrfs_cont_expand(struct inode *inode, loff_t size)
        u64 last_byte;
        u64 cur_offset;
        u64 hole_size;
-       int err;
+       int err = 0;
 
        if (size <= hole_start)
                return 0;
 
-       err = btrfs_check_metadata_free_space(root);
+       err = btrfs_truncate_page(inode->i_mapping, inode->i_size);
        if (err)
                return err;
 
-       btrfs_truncate_page(inode->i_mapping, inode->i_size);
-
        while (1) {
                struct btrfs_ordered_extent *ordered;
                btrfs_wait_ordered_range(inode, hole_start,
@@ -3024,12 +3216,18 @@ int btrfs_cont_expand(struct inode *inode, loff_t size)
                                                 cur_offset, &hint_byte, 1);
                        if (err)
                                break;
+
+                       err = btrfs_reserve_metadata_space(root, 1);
+                       if (err)
+                               break;
+
                        err = btrfs_insert_file_extent(trans, root,
                                        inode->i_ino, cur_offset, 0,
                                        0, hole_size, 0, hole_size,
                                        0, 0, 0);
                        btrfs_drop_extent_cache(inode, hole_start,
                                        last_byte - 1, 0);
+                       btrfs_unreserve_metadata_space(root, 1);
                }
                free_extent_map(em);
                cur_offset = last_byte;
@@ -3353,6 +3551,7 @@ static noinline void init_btrfs_i(struct inode *inode)
        bi->generation = 0;
        bi->sequence = 0;
        bi->last_trans = 0;
+       bi->last_sub_trans = 0;
        bi->logged_trans = 0;
        bi->delalloc_bytes = 0;
        bi->reserved_bytes = 0;
@@ -3503,12 +3702,14 @@ static int btrfs_dentry_delete(struct dentry *dentry)
 {
        struct btrfs_root *root;
 
-       if (!dentry->d_inode)
-               return 0;
+       if (!dentry->d_inode && !IS_ROOT(dentry))
+               dentry = dentry->d_parent;
 
-       root = BTRFS_I(dentry->d_inode)->root;
-       if (btrfs_root_refs(&root->root_item) == 0)
-               return 1;
+       if (dentry->d_inode) {
+               root = BTRFS_I(dentry->d_inode)->root;
+               if (btrfs_root_refs(&root->root_item) == 0)
+                       return 1;
+       }
        return 0;
 }
 
@@ -3990,11 +4191,18 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
        if (!new_valid_dev(rdev))
                return -EINVAL;
 
-       err = btrfs_check_metadata_free_space(root);
+       /*
+        * 2 for inode item and ref
+        * 2 for dir items
+        * 1 for xattr if selinux is on
+        */
+       err = btrfs_reserve_metadata_space(root, 5);
        if (err)
-               goto fail;
+               return err;
 
        trans = btrfs_start_transaction(root, 1);
+       if (!trans)
+               goto fail;
        btrfs_set_trans_block_group(trans, dir);
 
        err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
@@ -4032,6 +4240,7 @@ out_unlock:
        nr = trans->blocks_used;
        btrfs_end_transaction_throttle(trans, root);
 fail:
+       btrfs_unreserve_metadata_space(root, 5);
        if (drop_inode) {
                inode_dec_link_count(inode);
                iput(inode);
@@ -4052,10 +4261,18 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
        u64 objectid;
        u64 index = 0;
 
-       err = btrfs_check_metadata_free_space(root);
+       /*
+        * 2 for inode item and ref
+        * 2 for dir items
+        * 1 for xattr if selinux is on
+        */
+       err = btrfs_reserve_metadata_space(root, 5);
        if (err)
-               goto fail;
+               return err;
+
        trans = btrfs_start_transaction(root, 1);
+       if (!trans)
+               goto fail;
        btrfs_set_trans_block_group(trans, dir);
 
        err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
@@ -4096,6 +4313,7 @@ out_unlock:
        nr = trans->blocks_used;
        btrfs_end_transaction_throttle(trans, root);
 fail:
+       btrfs_unreserve_metadata_space(root, 5);
        if (drop_inode) {
                inode_dec_link_count(inode);
                iput(inode);
@@ -4118,10 +4336,16 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
        if (inode->i_nlink == 0)
                return -ENOENT;
 
-       btrfs_inc_nlink(inode);
-       err = btrfs_check_metadata_free_space(root);
+       /*
+        * 1 item for inode ref
+        * 2 items for dir items
+        */
+       err = btrfs_reserve_metadata_space(root, 3);
        if (err)
-               goto fail;
+               return err;
+
+       btrfs_inc_nlink(inode);
+
        err = btrfs_set_inode_index(dir, &index);
        if (err)
                goto fail;
@@ -4133,20 +4357,19 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
 
        err = btrfs_add_nondir(trans, dentry, inode, 1, index);
 
-       if (err)
-               drop_inode = 1;
-
-       btrfs_update_inode_block_group(trans, dir);
-       err = btrfs_update_inode(trans, root, inode);
-
-       if (err)
+       if (err) {
                drop_inode = 1;
+       } else {
+               btrfs_update_inode_block_group(trans, dir);
+               err = btrfs_update_inode(trans, root, inode);
+               BUG_ON(err);
+               btrfs_log_new_name(trans, inode, NULL, dentry->d_parent);
+       }
 
        nr = trans->blocks_used;
-
-       btrfs_log_new_name(trans, inode, NULL, dentry->d_parent);
        btrfs_end_transaction_throttle(trans, root);
 fail:
+       btrfs_unreserve_metadata_space(root, 3);
        if (drop_inode) {
                inode_dec_link_count(inode);
                iput(inode);
@@ -4166,17 +4389,21 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
        u64 index = 0;
        unsigned long nr = 1;
 
-       err = btrfs_check_metadata_free_space(root);
+       /*
+        * 2 items for inode and ref
+        * 2 items for dir items
+        * 1 for xattr if selinux is on
+        */
+       err = btrfs_reserve_metadata_space(root, 5);
        if (err)
-               goto out_unlock;
+               return err;
 
        trans = btrfs_start_transaction(root, 1);
-       btrfs_set_trans_block_group(trans, dir);
-
-       if (IS_ERR(trans)) {
-               err = PTR_ERR(trans);
+       if (!trans) {
+               err = -ENOMEM;
                goto out_unlock;
        }
+       btrfs_set_trans_block_group(trans, dir);
 
        err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
        if (err) {
@@ -4225,6 +4452,7 @@ out_fail:
        btrfs_end_transaction_throttle(trans, root);
 
 out_unlock:
+       btrfs_unreserve_metadata_space(root, 5);
        if (drop_on_err)
                iput(inode);
        btrfs_btree_balance_dirty(root, nr);
@@ -4686,7 +4914,8 @@ static void btrfs_invalidatepage(struct page *page, unsigned long offset)
                 */
                clear_extent_bit(tree, page_start, page_end,
                                 EXTENT_DIRTY | EXTENT_DELALLOC |
-                                EXTENT_LOCKED, 1, 0, NULL, GFP_NOFS);
+                                EXTENT_LOCKED | EXTENT_DO_ACCOUNTING, 1, 0,
+                                NULL, GFP_NOFS);
                /*
                 * whoever cleared the private bit is responsible
                 * for the finish_ordered_io
@@ -4699,8 +4928,8 @@ static void btrfs_invalidatepage(struct page *page, unsigned long offset)
                lock_extent(tree, page_start, page_end, GFP_NOFS);
        }
        clear_extent_bit(tree, page_start, page_end,
-                EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC,
-                1, 1, NULL, GFP_NOFS);
+                EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
+                EXTENT_DO_ACCOUNTING, 1, 1, NULL, GFP_NOFS);
        __btrfs_releasepage(page, GFP_NOFS);
 
        ClearPageChecked(page);
@@ -4749,6 +4978,13 @@ int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
                goto out;
        }
 
+       ret = btrfs_reserve_metadata_for_delalloc(root, inode, 1);
+       if (ret) {
+               btrfs_free_reserved_data_space(root, inode, PAGE_CACHE_SIZE);
+               ret = VM_FAULT_SIGBUS;
+               goto out;
+       }
+
        ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
 again:
        lock_page(page);
@@ -4780,7 +5016,24 @@ again:
                goto again;
        }
 
-       btrfs_set_extent_delalloc(inode, page_start, page_end);
+       /*
+        * XXX - page_mkwrite gets called every time the page is dirtied, even
+        * if it was already dirty, so for space accounting reasons we need to
+        * clear any delalloc bits for the range we are fixing to save.  There
+        * is probably a better way to do this, but for now keep consistent with
+        * prepare_pages in the normal write path.
+        */
+       clear_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end,
+                         EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING,
+                         GFP_NOFS);
+
+       ret = btrfs_set_extent_delalloc(inode, page_start, page_end);
+       if (ret) {
+               unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
+               ret = VM_FAULT_SIGBUS;
+               btrfs_free_reserved_data_space(root, inode, PAGE_CACHE_SIZE);
+               goto out_unlock;
+       }
        ret = 0;
 
        /* page is wholly or partially inside EOF */
@@ -4799,10 +5052,13 @@ again:
        set_page_dirty(page);
        SetPageUptodate(page);
 
-       BTRFS_I(inode)->last_trans = root->fs_info->generation + 1;
+       BTRFS_I(inode)->last_trans = root->fs_info->generation;
+       BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
+
        unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
 
 out_unlock:
+       btrfs_unreserve_metadata_for_delalloc(root, inode, 1);
        if (!ret)
                return VM_FAULT_LOCKED;
        unlock_page(page);
@@ -4823,7 +5079,9 @@ static void btrfs_truncate(struct inode *inode)
        if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
                return;
 
-       btrfs_truncate_page(inode->i_mapping, inode->i_size);
+       ret = btrfs_truncate_page(inode->i_mapping, inode->i_size);
+       if (ret)
+               return;
        btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1);
 
        trans = btrfs_start_transaction(root, 1);
@@ -4918,7 +5176,12 @@ struct inode *btrfs_alloc_inode(struct super_block *sb)
        if (!ei)
                return NULL;
        ei->last_trans = 0;
+       ei->last_sub_trans = 0;
        ei->logged_trans = 0;
+       ei->outstanding_extents = 0;
+       ei->reserved_extents = 0;
+       ei->root = NULL;
+       spin_lock_init(&ei->accounting_lock);
        btrfs_ordered_inode_tree_init(&ei->ordered_tree);
        INIT_LIST_HEAD(&ei->i_orphan);
        INIT_LIST_HEAD(&ei->ordered_operations);
@@ -4934,6 +5197,14 @@ void btrfs_destroy_inode(struct inode *inode)
        WARN_ON(inode->i_data.nrpages);
 
        /*
+        * This can happen where we create an inode, but somebody else also
+        * created the same inode and we need to destroy the one we already
+        * created.
+        */
+       if (!root)
+               goto free;
+
+       /*
         * Make sure we're properly removed from the ordered operation
         * lists.
         */
@@ -4968,6 +5239,7 @@ void btrfs_destroy_inode(struct inode *inode)
        }
        inode_tree_del(inode);
        btrfs_drop_extent_cache(inode, 0, (u64)-1, 0);
+free:
        kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
 }
 
@@ -5057,6 +5329,9 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
        u64 root_objectid;
        int ret;
 
+       if (new_dir->i_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
+               return -EPERM;
+
        /* we only allow rename subvolume link between subvolumes */
        if (old_inode->i_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
                return -EXDEV;
@@ -5069,7 +5344,15 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
            new_inode->i_size > BTRFS_EMPTY_DIR_SIZE)
                return -ENOTEMPTY;
 
-       ret = btrfs_check_metadata_free_space(root);
+       /*
+        * We want to reserve the absolute worst case amount of items.  So if
+        * both inodes are subvols and we need to unlink them then that would
+        * require 4 item modifications, but if they are both normal inodes it
+        * would require 5 item modifications, so we'll assume their normal
+        * inodes.  So 5 * 2 is 10, plus 1 for the new link, so 11 total items
+        * should cover the worst case number of items we'll modify.
+        */
+       ret = btrfs_reserve_metadata_space(root, 11);
        if (ret)
                return ret;
 
@@ -5087,23 +5370,26 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
                down_read(&root->fs_info->subvol_sem);
 
        trans = btrfs_start_transaction(root, 1);
+       btrfs_set_trans_block_group(trans, new_dir);
 
        if (dest != root)
                btrfs_record_root_in_trans(trans, dest);
 
-       /*
-        * make sure the inode gets flushed if it is replacing
-        * something.
-        */
-       if (new_inode && new_inode->i_size &&
-           old_inode && S_ISREG(old_inode->i_mode)) {
-               btrfs_add_ordered_operation(trans, root, old_inode);
-       }
+       ret = btrfs_set_inode_index(new_dir, &index);
+       if (ret)
+               goto out_fail;
 
-       if (old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) {
+       if (unlikely(old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) {
                /* force full log commit if subvolume involved. */
                root->fs_info->last_trans_log_full_commit = trans->transid;
        } else {
+               ret = btrfs_insert_inode_ref(trans, dest,
+                                            new_dentry->d_name.name,
+                                            new_dentry->d_name.len,
+                                            old_inode->i_ino,
+                                            new_dir->i_ino, index);
+               if (ret)
+                       goto out_fail;
                /*
                 * this is an ugly little race, but the rename is required
                 * to make sure that if we crash, the inode is either at the
@@ -5113,8 +5399,14 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
                 */
                btrfs_pin_log_trans(root);
        }
-
-       btrfs_set_trans_block_group(trans, new_dir);
+       /*
+        * make sure the inode gets flushed if it is replacing
+        * something.
+        */
+       if (new_inode && new_inode->i_size &&
+           old_inode && S_ISREG(old_inode->i_mode)) {
+               btrfs_add_ordered_operation(trans, root, old_inode);
+       }
 
        old_dir->i_ctime = old_dir->i_mtime = ctime;
        new_dir->i_ctime = new_dir->i_mtime = ctime;
@@ -5159,12 +5451,10 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
                        BUG_ON(ret);
                }
        }
-       ret = btrfs_set_inode_index(new_dir, &index);
-       BUG_ON(ret);
 
        ret = btrfs_add_link(trans, new_dir, old_inode,
                             new_dentry->d_name.name,
-                            new_dentry->d_name.len, 1, index);
+                            new_dentry->d_name.len, 0, index);
        BUG_ON(ret);
 
        if (old_inode->i_ino != BTRFS_FIRST_FREE_OBJECTID) {
@@ -5172,11 +5462,13 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
                                   new_dentry->d_parent);
                btrfs_end_log_trans(root);
        }
-
+out_fail:
        btrfs_end_transaction_throttle(trans, root);
 
        if (old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)
                up_read(&root->fs_info->subvol_sem);
+
+       btrfs_unreserve_metadata_space(root, 11);
        return ret;
 }
 
@@ -5248,11 +5540,18 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
        if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
                return -ENAMETOOLONG;
 
-       err = btrfs_check_metadata_free_space(root);
+       /*
+        * 2 items for inode item and ref
+        * 2 items for dir items
+        * 1 item for xattr if selinux is on
+        */
+       err = btrfs_reserve_metadata_space(root, 5);
        if (err)
-               goto out_fail;
+               return err;
 
        trans = btrfs_start_transaction(root, 1);
+       if (!trans)
+               goto out_fail;
        btrfs_set_trans_block_group(trans, dir);
 
        err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
@@ -5333,6 +5632,7 @@ out_unlock:
        nr = trans->blocks_used;
        btrfs_end_transaction_throttle(trans, root);
 out_fail:
+       btrfs_unreserve_metadata_space(root, 5);
        if (drop_inode) {
                inode_dec_link_count(inode);
                iput(inode);
@@ -5354,6 +5654,11 @@ static int prealloc_file_range(struct btrfs_trans_handle *trans,
 
        while (num_bytes > 0) {
                alloc_size = min(num_bytes, root->fs_info->max_extent);
+
+               ret = btrfs_reserve_metadata_space(root, 1);
+               if (ret)
+                       goto out;
+
                ret = btrfs_reserve_extent(trans, root, alloc_size,
                                           root->sectorsize, 0, alloc_hint,
                                           (u64)-1, &ins, 1);
@@ -5373,6 +5678,7 @@ static int prealloc_file_range(struct btrfs_trans_handle *trans,
                num_bytes -= ins.offset;
                cur_offset += ins.offset;
                alloc_hint = ins.objectid + ins.offset;
+               btrfs_unreserve_metadata_space(root, 1);
        }
 out:
        if (cur_offset > start) {
@@ -5513,7 +5819,7 @@ static int btrfs_permission(struct inode *inode, int mask)
        return generic_permission(inode, mask, btrfs_check_acl);
 }
 
-static struct inode_operations btrfs_dir_inode_operations = {
+static const struct inode_operations btrfs_dir_inode_operations = {
        .getattr        = btrfs_getattr,
        .lookup         = btrfs_lookup,
        .create         = btrfs_create,
@@ -5531,12 +5837,12 @@ static struct inode_operations btrfs_dir_inode_operations = {
        .removexattr    = btrfs_removexattr,
        .permission     = btrfs_permission,
 };
-static struct inode_operations btrfs_dir_ro_inode_operations = {
+static const struct inode_operations btrfs_dir_ro_inode_operations = {
        .lookup         = btrfs_lookup,
        .permission     = btrfs_permission,
 };
 
-static struct file_operations btrfs_dir_file_operations = {
+static const struct file_operations btrfs_dir_file_operations = {
        .llseek         = generic_file_llseek,
        .read           = generic_read_dir,
        .readdir        = btrfs_real_readdir,
@@ -5558,6 +5864,8 @@ static struct extent_io_ops btrfs_extent_io_ops = {
        .readpage_io_failed_hook = btrfs_io_failed_hook,
        .set_bit_hook = btrfs_set_bit_hook,
        .clear_bit_hook = btrfs_clear_bit_hook,
+       .merge_extent_hook = btrfs_merge_extent_hook,
+       .split_extent_hook = btrfs_split_extent_hook,
 };
 
 /*
@@ -5572,7 +5880,7 @@ static struct extent_io_ops btrfs_extent_io_ops = {
  *
  * For now we're avoiding this by dropping bmap.
  */
-static struct address_space_operations btrfs_aops = {
+static const struct address_space_operations btrfs_aops = {
        .readpage       = btrfs_readpage,
        .writepage      = btrfs_writepage,
        .writepages     = btrfs_writepages,
@@ -5582,16 +5890,17 @@ static struct address_space_operations btrfs_aops = {
        .invalidatepage = btrfs_invalidatepage,
        .releasepage    = btrfs_releasepage,
        .set_page_dirty = btrfs_set_page_dirty,
+       .error_remove_page = generic_error_remove_page,
 };
 
-static struct address_space_operations btrfs_symlink_aops = {
+static const struct address_space_operations btrfs_symlink_aops = {
        .readpage       = btrfs_readpage,
        .writepage      = btrfs_writepage,
        .invalidatepage = btrfs_invalidatepage,
        .releasepage    = btrfs_releasepage,
 };
 
-static struct inode_operations btrfs_file_inode_operations = {
+static const struct inode_operations btrfs_file_inode_operations = {
        .truncate       = btrfs_truncate,
        .getattr        = btrfs_getattr,
        .setattr        = btrfs_setattr,
@@ -5603,7 +5912,7 @@ static struct inode_operations btrfs_file_inode_operations = {
        .fallocate      = btrfs_fallocate,
        .fiemap         = btrfs_fiemap,
 };
-static struct inode_operations btrfs_special_inode_operations = {
+static const struct inode_operations btrfs_special_inode_operations = {
        .getattr        = btrfs_getattr,
        .setattr        = btrfs_setattr,
        .permission     = btrfs_permission,
@@ -5612,7 +5921,7 @@ static struct inode_operations btrfs_special_inode_operations = {
        .listxattr      = btrfs_listxattr,
        .removexattr    = btrfs_removexattr,
 };
-static struct inode_operations btrfs_symlink_inode_operations = {
+static const struct inode_operations btrfs_symlink_inode_operations = {
        .readlink       = generic_readlink,
        .follow_link    = page_follow_link_light,
        .put_link       = page_put_link,
@@ -5623,6 +5932,6 @@ static struct inode_operations btrfs_symlink_inode_operations = {
        .removexattr    = btrfs_removexattr,
 };
 
-struct dentry_operations btrfs_dentry_operations = {
+const struct dentry_operations btrfs_dentry_operations = {
        .d_delete       = btrfs_dentry_delete,
 };