Btrfs: Allow tails larger than one page

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 116 insertions, 36 deletions

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 844d8807e44a..1af2b6534dad 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -82,8 +82,9 @@ static void btrfs_drop_pages(struct page **pages, size_t num_pages)
 
 static int insert_inline_extent(struct btrfs_trans_handle *trans,
                                 struct btrfs_root *root, struct inode *inode,
-                                u64 offset, ssize_t size,
-                                struct page *page, size_t page_offset)
+                                u64 offset, size_t size,
+                                struct page **pages, size_t page_offset,
+                                int num_pages)
 {
         struct btrfs_key key;
         struct btrfs_path *path;
@@ -91,9 +92,12 @@ static int insert_inline_extent(struct btrfs_trans_handle *trans,
         char *kaddr;
         unsigned long ptr;
         struct btrfs_file_extent_item *ei;
+        struct page *page;
         u32 datasize;
         int err = 0;
         int ret;
+        int i;
+        ssize_t cur_size;
 
         path = btrfs_alloc_path();
         if (!path)
@@ -104,25 +108,97 @@ static int insert_inline_extent(struct btrfs_trans_handle *trans,
         key.objectid = inode->i_ino;
         key.offset = offset;
         btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
-        BUG_ON(size >= PAGE_CACHE_SIZE);
-        datasize = btrfs_file_extent_calc_inline_size(size);
+        datasize = btrfs_file_extent_calc_inline_size(offset + size);
 
-        ret = btrfs_insert_empty_item(trans, root, path, &key,
-                                      datasize);
-        if (ret) {
+        ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
+        if (ret < 0) {
                 err = ret;
                 goto fail;
         }
-        leaf = path->nodes[0];
-        ei = btrfs_item_ptr(leaf, path->slots[0],
-                            struct btrfs_file_extent_item);
-        btrfs_set_file_extent_generation(leaf, ei, trans->transid);
-        btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE);
-        ptr = btrfs_file_extent_inline_start(ei);
-
-        kaddr = kmap_atomic(page, KM_USER1);
-        write_extent_buffer(leaf, kaddr + page_offset, ptr, size);
-        kunmap_atomic(kaddr, KM_USER1);
+        if (ret == 1) {
+                path->slots[0]--;
+                leaf = path->nodes[0];
+                ei = btrfs_item_ptr(leaf, path->slots[0],
+                                    struct btrfs_file_extent_item);
+
+                if (btrfs_file_extent_type(leaf, ei) !=
+                    BTRFS_FILE_EXTENT_INLINE) {
+                        goto insert;
+                }
+                btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+                ret = 0;
+        }
+        if (ret == 0) {
+                u32 found_size;
+                u64 found_start;
+
+                leaf = path->nodes[0];
+                ei = btrfs_item_ptr(leaf, path->slots[0],
+                                    struct btrfs_file_extent_item);
+
+                if (btrfs_file_extent_type(leaf, ei) !=
+                    BTRFS_FILE_EXTENT_INLINE) {
+                        err = ret;
+                        btrfs_print_leaf(root, leaf);
+                        printk("found wasn't inline offset %Lu inode %lu\n",
+                               offset, inode->i_ino);
+                        goto fail;
+                }
+                found_start = key.offset;
+                found_size = btrfs_file_extent_inline_len(leaf,
+                                          btrfs_item_nr(leaf, path->slots[0]));
+
+                if (found_size < offset + size) {
+                        btrfs_release_path(root, path);
+                        ret = btrfs_search_slot(trans, root, &key, path,
+                                                offset + size - found_size -
+                                                found_start, 1);
+                        BUG_ON(ret != 0);
+                        ret = btrfs_extend_item(trans, root, path,
+                                                offset + size - found_size -
+                                                found_start);
+                        if (ret) {
+                                err = ret;
+                                goto fail;
+                        }
+                        leaf = path->nodes[0];
+                        ei = btrfs_item_ptr(leaf, path->slots[0],
+                                            struct btrfs_file_extent_item);
+                }
+        } else {
+insert:
+                btrfs_release_path(root, path);
+                ret = btrfs_insert_empty_item(trans, root, path, &key,
+                                              datasize);
+                if (ret) {
+                        err = ret;
+                        printk("got bad ret %d\n", ret);
+                        goto fail;
+                }
+                leaf = path->nodes[0];
+                ei = btrfs_item_ptr(leaf, path->slots[0],
+                                    struct btrfs_file_extent_item);
+                btrfs_set_file_extent_generation(leaf, ei, trans->transid);
+                btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE);
+        }
+        ptr = btrfs_file_extent_inline_start(ei) + offset;
+
+        cur_size = size;
+        i = 0;
+        while (size > 0) {
+                page = pages[i];
+                kaddr = kmap_atomic(page, KM_USER0);
+                cur_size = min(PAGE_CACHE_SIZE - page_offset, size);
+                write_extent_buffer(leaf, kaddr + page_offset, ptr, cur_size);
+                kunmap_atomic(kaddr, KM_USER0);
+                page_offset = 0;
+                ptr += cur_size;
+                size -= cur_size;
+                if (i >= num_pages) {
+                        printk("i %d num_pages %d\n", i, num_pages);
+                }
+                i++;
+        }
         btrfs_mark_buffer_dirty(leaf);
 fail:
         btrfs_free_path(path);
@@ -193,6 +269,7 @@ static int dirty_and_release_pages(struct btrfs_trans_handle *trans,
                         err = btrfs_drop_extents(trans, root, inode,
                                                  last_pos_in_file,
                                                  last_pos_in_file + hole_size,
+                                                 last_pos_in_file,
                                                  &hint_byte);
                         if (err)
                                 goto failed;
@@ -210,11 +287,12 @@ static int dirty_and_release_pages(struct btrfs_trans_handle *trans,
          * either allocate an extent for the new bytes or setup the key
          * to show we are doing inline data in the extent
          */
-        inline_size = end_pos - start_pos;
-        if (isize >= PAGE_CACHE_SIZE || pos + write_bytes < inode->i_size ||
-            inline_size >= BTRFS_MAX_INLINE_DATA_SIZE(root) ||
-            inline_size >= PAGE_CACHE_SIZE) {
+        inline_size = end_pos;
+        if (isize >= BTRFS_MAX_INLINE_DATA_SIZE(root) ||
+            inline_size > 16384 ||
+            inline_size >= BTRFS_MAX_INLINE_DATA_SIZE(root)) {
                 u64 last_end;
+
                 for (i = 0; i < num_pages; i++) {
                         struct page *p = pages[i];
                         SetPageUptodate(p);
@@ -225,22 +303,18 @@ static int dirty_and_release_pages(struct btrfs_trans_handle *trans,
                 set_extent_delalloc(em_tree, start_pos, end_of_last_block,
                                  GFP_NOFS);
         } else {
-                struct page *p = pages[0];
+                u64 aligned_end;
                 /* step one, delete the existing extents in this range */
+                aligned_end = (pos + write_bytes + root->sectorsize - 1) &
+                        ~((u64)root->sectorsize - 1);
                 err = btrfs_drop_extents(trans, root, inode, start_pos,
-                         (pos + write_bytes + root->sectorsize -1) &
-                         ~((u64)root->sectorsize - 1), &hint_byte);
+                                         aligned_end, end_pos, &hint_byte);
                 if (err)
                         goto failed;
-
                 err = insert_inline_extent(trans, root, inode, start_pos,
-                                           end_pos - start_pos, p, 0);
+                                           end_pos - start_pos, pages, 0,
+                                           num_pages);
                 BUG_ON(err);
-                em->start = start_pos;
-                em->end = end_pos - 1;
-                em->block_start = EXTENT_MAP_INLINE;
-                em->block_end = EXTENT_MAP_INLINE;
-                add_extent_mapping(em_tree, em);
         }
         if (end_pos > isize) {
                 i_size_write(inode, end_pos);
@@ -285,7 +359,7 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end)
  */
 int btrfs_drop_extents(struct btrfs_trans_handle *trans,
                        struct btrfs_root *root, struct inode *inode,
-                       u64 start, u64 end, u64 *hint_byte)
+                       u64 start, u64 end, u64 inline_end, u64 *hint_byte)
 {
         int ret;
         struct btrfs_key key;
@@ -401,8 +475,8 @@ next_slot:
                                         BUG_ON(ret);
                                 }
                         }
-                        WARN_ON(found_inline);
-                        bookend = 1;
+                        if (!found_inline)
+                                bookend = 1;
                 }
                 /* truncate existing extent */
                 if (start > key.offset) {
@@ -425,8 +499,14 @@ next_slot:
                                 btrfs_set_file_extent_num_bytes(leaf, extent,
                                                                 new_num);
                                 btrfs_mark_buffer_dirty(leaf);
-                        } else {
-                                WARN_ON(1);
+                        } else if (end > extent_end &&
+                                   key.offset < inline_end &&
+                                   inline_end < extent_end) {
+                                u32 new_size;
+                                new_size = btrfs_file_extent_calc_inline_size(
+                                                   inline_end - key.offset);
+                                btrfs_truncate_item(trans, root, path,
+                                                    new_size);
                         }
                 }
                 /* delete the entire extent */