Btrfs: log changed inodes based on the extent map tree

[cascardo/linux.git] / fs / btrfs / inode.c

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 73e6833..355a297 100644 (file)
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -95,6 +95,10 @@ static noinline int cow_file_range(struct inode *inode,
                                   struct page *locked_page,
                                   u64 start, u64 end, int *page_started,
                                   unsigned long *nr_written, int unlock);
+static struct extent_map *create_pinned_em(struct inode *inode, u64 start,
+                                          u64 len, u64 orig_start,
+                                          u64 block_start, u64 block_len,
+                                          u64 orig_block_len, int type);
 
 static int btrfs_init_inode_security(struct btrfs_trans_handle *trans,
                                     struct inode *inode,  struct inode *dir,
@@ -704,10 +708,14 @@ retry:
                em->compress_type = async_extent->compress_type;
                set_bit(EXTENT_FLAG_PINNED, &em->flags);
                set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
+               em->generation = -1;
 
                while (1) {
                        write_lock(&em_tree->lock);
                        ret = add_extent_mapping(em_tree, em);
+                       if (!ret)
+                               list_move(&em->list,
+                                         &em_tree->modified_extents);
                        write_unlock(&em_tree->lock);
                        if (ret != -EEXIST) {
                                free_extent_map(em);
@@ -890,10 +898,14 @@ static noinline int __cow_file_range(struct btrfs_trans_handle *trans,
                em->orig_block_len = ins.offset;
                em->bdev = root->fs_info->fs_devices->latest_bdev;
                set_bit(EXTENT_FLAG_PINNED, &em->flags);
+               em->generation = -1;
 
                while (1) {
                        write_lock(&em_tree->lock);
                        ret = add_extent_mapping(em_tree, em);
+                       if (!ret)
+                               list_move(&em->list,
+                                         &em_tree->modified_extents);
                        write_unlock(&em_tree->lock);
                        if (ret != -EEXIST) {
                                free_extent_map(em);
@@ -1320,7 +1332,7 @@ out_check:
                        em = alloc_extent_map();
                        BUG_ON(!em); /* -ENOMEM */
                        em->start = cur_offset;
-                       em->orig_start = em->start;
+                       em->orig_start = found_key.offset - extent_offset;
                        em->len = num_bytes;
                        em->block_len = num_bytes;
                        em->block_start = disk_bytenr;
@@ -1328,9 +1340,13 @@ out_check:
                        em->bdev = root->fs_info->fs_devices->latest_bdev;
                        set_bit(EXTENT_FLAG_PINNED, &em->flags);
                        set_bit(EXTENT_FLAG_FILLING, &em->flags);
+                       em->generation = -1;
                        while (1) {
                                write_lock(&em_tree->lock);
                                ret = add_extent_mapping(em_tree, em);
+                               if (!ret)
+                                       list_move(&em->list,
+                                                 &em_tree->modified_extents);
                                write_unlock(&em_tree->lock);
                                if (ret != -EEXIST) {
                                        free_extent_map(em);
@@ -5371,6 +5387,7 @@ again:
                if (start + len <= found_key.offset)
                        goto not_found;
                em->start = start;
+               em->orig_start = start;
                em->len = found_key.offset - start;
                goto not_found_em;
        }
@@ -5423,7 +5440,7 @@ again:
                em->len = (copy_size + root->sectorsize - 1) &
                        ~((u64)root->sectorsize - 1);
                em->orig_block_len = em->len;
-               em->orig_start = EXTENT_MAP_INLINE;
+               em->orig_start = em->start;
                if (compress_type) {
                        set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
                        em->compress_type = compress_type;
@@ -5476,6 +5493,7 @@ again:
        }
 not_found:
        em->start = start;
+       em->orig_start = start;
        em->len = len;
 not_found_em:
        em->block_start = EXTENT_MAP_HOLE;
@@ -5677,30 +5695,14 @@ out:
 }
 
 static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
-                                                 struct extent_map *em,
                                                  u64 start, u64 len)
 {
        struct btrfs_root *root = BTRFS_I(inode)->root;
        struct btrfs_trans_handle *trans;
-       struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
+       struct extent_map *em;
        struct btrfs_key ins;
        u64 alloc_hint;
        int ret;
-       bool insert = false;
-
-       /*
-        * Ok if the extent map we looked up is a hole and is for the exact
-        * range we want, there is no reason to allocate a new one, however if
-        * it is not right then we need to free this one and drop the cache for
-        * our range.
-        */
-       if (em->block_start != EXTENT_MAP_HOLE || em->start != start ||
-           em->len != len) {
-               free_extent_map(em);
-               em = NULL;
-               insert = true;
-               btrfs_drop_extent_cache(inode, start, start + len - 1, 0);
-       }
 
        trans = btrfs_join_transaction(root);
        if (IS_ERR(trans))
@@ -5716,38 +5718,10 @@ static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
                goto out;
        }
 
-       if (!em) {
-               em = alloc_extent_map();
-               if (!em) {
-                       em = ERR_PTR(-ENOMEM);
-                       goto out;
-               }
-       }
-
-       em->start = start;
-       em->orig_start = em->start;
-       em->len = ins.offset;
-
-       em->block_start = ins.objectid;
-       em->block_len = ins.offset;
-       em->orig_block_len = ins.offset;
-       em->bdev = root->fs_info->fs_devices->latest_bdev;
-
-       /*
-        * We need to do this because if we're using the original em we searched
-        * for, we could have EXTENT_FLAG_VACANCY set, and we don't want that.
-        */
-       em->flags = 0;
-       set_bit(EXTENT_FLAG_PINNED, &em->flags);
-
-       while (insert) {
-               write_lock(&em_tree->lock);
-               ret = add_extent_mapping(em_tree, em);
-               write_unlock(&em_tree->lock);
-               if (ret != -EEXIST)
-                       break;
-               btrfs_drop_extent_cache(inode, start, start + em->len - 1, 0);
-       }
+       em = create_pinned_em(inode, start, ins.offset, start, ins.objectid,
+                             ins.offset, ins.offset, 0);
+       if (IS_ERR(em))
+               goto out;
 
        ret = btrfs_add_ordered_extent_dio(inode, start, ins.objectid,
                                           ins.offset, ins.offset, 0);
@@ -5943,6 +5917,7 @@ static struct extent_map *create_pinned_em(struct inode *inode, u64 start,
        em->block_start = block_start;
        em->bdev = root->fs_info->fs_devices->latest_bdev;
        em->orig_block_len = orig_block_len;
+       em->generation = -1;
        set_bit(EXTENT_FLAG_PINNED, &em->flags);
        if (type == BTRFS_ORDERED_PREALLOC)
                set_bit(EXTENT_FLAG_FILLING, &em->flags);
@@ -5952,6 +5927,9 @@ static struct extent_map *create_pinned_em(struct inode *inode, u64 start,
                                em->start + em->len - 1, 0);
                write_lock(&em_tree->lock);
                ret = add_extent_mapping(em_tree, em);
+               if (!ret)
+                       list_move(&em->list,
+                                 &em_tree->modified_extents);
                write_unlock(&em_tree->lock);
        } while (ret == -EEXIST);
 
@@ -6078,7 +6056,7 @@ static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
                        goto must_cow;
 
                if (can_nocow_odirect(trans, inode, start, len) == 1) {
-                       u64 orig_start = em->start;
+                       u64 orig_start = em->orig_start;
                        u64 orig_block_len = em->orig_block_len;
 
                        if (type == BTRFS_ORDERED_PREALLOC) {
@@ -6110,7 +6088,8 @@ must_cow:
         * it above
         */
        len = bh_result->b_size;
-       em = btrfs_new_extent_direct(inode, em, start, len);
+       free_extent_map(em);
+       em = btrfs_new_extent_direct(inode, start, len);
        if (IS_ERR(em)) {
                ret = PTR_ERR(em);
                goto unlock_err;