Btrfs: rework csums and extent item ordering

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

6 files changed, 37 insertions, 168 deletions

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 43d4779abdd1..5c160c236773 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -115,14 +115,14 @@ static int comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2)
                 return 1;
         if (k1.objectid < k2->objectid)
                 return -1;
-        if (k1.offset > k2->offset)
-                return 1;
-        if (k1.offset < k2->offset)
-                return -1;
         if (k1.flags > k2->flags)
                 return 1;
         if (k1.flags < k2->flags)
                 return -1;
+        if (k1.offset > k2->offset)
+                return 1;
+        if (k1.offset < k2->offset)
+                return -1;
         return 0;
 }
 
@@ -1292,7 +1292,6 @@ int btrfs_truncate_item(struct btrfs_trans_handle *trans,
                                       ioff + size_diff);
         }
         /* shift the data */
-printk("truncate item, new_size %u old_size %u, diff %u, bufp %p, dst, %p, num %u, old_data_start %u, data_end %u\n", new_size, old_size, size_diff, leaf, btrfs_leaf_data(leaf) + data_end + size_diff, old_data_start-data_end, old_data_start, data_end);
         btrfs_memmove(root, leaf, btrfs_leaf_data(leaf) +
                       data_end + size_diff, btrfs_leaf_data(leaf) +
                       data_end, old_data_start + new_size - data_end);
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index ca3ab160f460..d75a4d5bc010 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -44,14 +44,14 @@ extern struct kmem_cache *btrfs_path_cachep;
  */
 struct btrfs_disk_key {
         __le64 objectid;
-        __le64 offset;
         __le32 flags;
+        __le64 offset;
 } __attribute__ ((__packed__));
 
 struct btrfs_key {
         u64 objectid;
-        u64 offset;
         u32 flags;
+        u64 offset;
 } __attribute__ ((__packed__));
 
 /*
@@ -227,7 +227,6 @@ struct btrfs_file_extent_item {
 } __attribute__ ((__packed__));
 
 struct btrfs_csum_item {
-        __le64 extent_offset;
         u8 csum[BTRFS_CSUM_SIZE];
 } __attribute__ ((__packed__));
 
@@ -925,17 +924,6 @@ static inline void btrfs_set_file_extent_num_blocks(struct
         e->num_blocks = cpu_to_le64(val);
 }
 
-static inline u64 btrfs_csum_extent_offset(struct btrfs_csum_item *c)
-{
-        return le64_to_cpu(c->extent_offset);
-}
-
-static inline void btrfs_set_csum_extent_offset(struct btrfs_csum_item *c,
-                                                u64 val)
-{
-        c->extent_offset = cpu_to_le64(val);
-}
-
 static inline u16 btrfs_device_pathlen(struct btrfs_device_item *d)
 {
         return le16_to_cpu(d->pathlen);
@@ -1091,7 +1079,6 @@ int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
 int btrfs_csum_file_block(struct btrfs_trans_handle *trans,
                           struct btrfs_root *root,
                           u64 objectid, u64 offset,
-                          u64 extent_offset,
                           char *data, size_t len);
 int btrfs_csum_verify_file_block(struct btrfs_root *root,
                                  u64 objectid, u64 offset,
diff --git a/fs/btrfs/dir-item.c b/fs/btrfs/dir-item.c
index 0ba46bc0da9a..cd4137a8b87e 100644
--- a/fs/btrfs/dir-item.c
+++ b/fs/btrfs/dir-item.c
@@ -103,7 +103,7 @@ int btrfs_lookup_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
         key.objectid = dir;
         key.flags = 0;
         btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
-        btrfs_set_key_overflow(&key, BTRFS_KEY_OVERFLOW_MAX - 1);
+        // btrfs_set_key_overflow(&key, BTRFS_KEY_OVERFLOW_MAX - 1);
         ret = btrfs_name_hash(name, name_len, &key.offset);
         BUG_ON(ret);
         while(1) {
@@ -146,19 +146,29 @@ int btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans,
         int cow = mod != 0;
         struct btrfs_disk_key *found_key;
         struct btrfs_leaf *leaf;
+        int overflow = 0;
 
         key.objectid = dir;
         key.flags = 0;
         btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
-        btrfs_set_key_overflow(&key, BTRFS_KEY_OVERFLOW_MAX - 1);
         key.offset = objectid;
-        ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
-        if (ret < 0)
-                return ret;
-        if (ret > 0) {
-                if (path->slots[0] == 0)
-                        return 1;
-                path->slots[0]--;
+
+        while(1) {
+                btrfs_set_key_overflow(&key, overflow);
+                ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
+                if (ret < 0)
+                        return ret;
+                if (ret > 0) {
+                        if (overflow >= BTRFS_KEY_OVERFLOW_MAX)
+                                return 1;
+                        overflow++;
+                        btrfs_set_key_overflow(&key, overflow);
+                        btrfs_release_path(root, path);
+                        continue;
+                } else {
+                        /* found */
+                        break;
+                }
         }
         leaf = btrfs_buffer_leaf(path->nodes[0]);
         found_key = &leaf->items[path->slots[0]].key;
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 06b969c14625..a2a3f529cada 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -24,7 +24,6 @@ int btrfs_insert_dev_radix(struct btrfs_root *root,
                            u64 num_blocks)
 {
         struct dev_lookup *lookup;
-        char b[BDEVNAME_SIZE];
         int ret;
 
         lookup = kmalloc(sizeof(*lookup), GFP_NOFS);
@@ -34,7 +33,6 @@ int btrfs_insert_dev_radix(struct btrfs_root *root,
         lookup->num_blocks = num_blocks;
         lookup->bdev = bdev;
         lookup->device_id = device_id;
-printk("inserting %s into dev radix %Lu %Lu\n", bdevname(bdev, b), block_start, num_blocks);
 
         ret = radix_tree_insert(&root->fs_info->dev_radix, block_start +
                                 num_blocks - 1, lookup);
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index f49968ad0a07..ff8f3339c684 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -62,23 +62,19 @@ struct btrfs_csum_item *btrfs_lookup_csum(struct btrfs_trans_handle *trans,
         file_key.offset = offset;
         file_key.flags = 0;
         btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY);
-printk("__lookup for %Lu\n", offset);
         ret = btrfs_search_slot(trans, root, &file_key, path, 0, cow);
         if (ret < 0)
                 goto fail;
         leaf = btrfs_buffer_leaf(path->nodes[0]);
         if (ret > 0) {
                 ret = 1;
-                if (path->slots[0] == 0) {
-printk("fail1\n");
+                if (path->slots[0] == 0)
                         goto fail;
-                }
                 path->slots[0]--;
                 btrfs_disk_key_to_cpu(&found_key,
                                       &leaf->items[path->slots[0]].key);
                 if (btrfs_key_type(&found_key) != BTRFS_CSUM_ITEM_KEY ||
                     found_key.objectid != objectid) {
-printk("fail2 type %u %Lu %Lu\n", btrfs_key_type(&found_key), found_key.objectid, objectid);
                         goto fail;
                 }
                 csum_offset = (offset - found_key.offset) >>
@@ -86,7 +82,6 @@ printk("fail2 type %u %Lu %Lu\n", btrfs_key_type(&found_key), found_key.objectid
                 if (csum_offset >=
                     btrfs_item_size(leaf->items + path->slots[0]) /
                     sizeof(struct btrfs_csum_item)) {
-printk("fail3, csum offset %lu size %u\n", csum_offset, btrfs_item_size(leaf->items + path->slots[0]) / sizeof(struct btrfs_csum_item));
                         goto fail;
                 }
         }
@@ -109,26 +104,18 @@ int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
         struct btrfs_key file_key;
         int ins_len = mod < 0 ? -1 : 0;
         int cow = mod != 0;
-        struct btrfs_csum_item *csum_item;
 
-        csum_item = btrfs_lookup_csum(trans, root, path, objectid, offset, 0);
-        if (IS_ERR(csum_item))
-                return PTR_ERR(csum_item);
         file_key.objectid = objectid;
-        file_key.offset = btrfs_csum_extent_offset(csum_item);
+        file_key.offset = offset;
         file_key.flags = 0;
         btrfs_set_key_type(&file_key, BTRFS_EXTENT_DATA_KEY);
-        btrfs_release_path(root, path);
-printk("lookup file extent searches for %Lu\n", file_key.offset);
         ret = btrfs_search_slot(trans, root, &file_key, path, ins_len, cow);
-printk("ret is %d\n", ret);
         return ret;
 }
 
 int btrfs_csum_file_block(struct btrfs_trans_handle *trans,
                           struct btrfs_root *root,
                           u64 objectid, u64 offset,
-                          u64 extent_offset,
                           char *data, size_t len)
 {
         int ret;
@@ -151,10 +138,8 @@ int btrfs_csum_file_block(struct btrfs_trans_handle *trans,
         file_key.offset = offset;
         file_key.flags = 0;
         btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY);
-printk("searching for csum %Lu %Lu\n", objectid, offset);
         ret = btrfs_search_slot(trans, root, &file_key, path,
                                 sizeof(struct btrfs_csum_item), 1);
-printk("ret %d\n", ret);
         if (ret < 0)
                 goto fail;
         if (ret == 0) {
@@ -167,15 +152,12 @@ printk("ret %d\n", ret);
         path->slots[0]--;
         leaf = btrfs_buffer_leaf(path->nodes[0]);
         btrfs_disk_key_to_cpu(&found_key, &leaf->items[path->slots[0]].key);
-printk("found key %Lu %Lu %u\n", found_key.objectid, found_key.offset, found_key.flags);
         csum_offset = (offset - found_key.offset) >>
                         root->fs_info->sb->s_blocksize_bits;
-printk("csum_offset %Lu\n", csum_offset);
         if (btrfs_key_type(&found_key) != BTRFS_CSUM_ITEM_KEY ||
             found_key.objectid != objectid ||
             csum_offset >= MAX_CSUM_ITEMS(root)) {
                 btrfs_release_path(root, path);
-printk("insert1\n");
                 goto insert;
         }
         if (csum_offset >= btrfs_item_size(leaf->items + path->slots[0]) /
@@ -183,13 +165,11 @@ printk("insert1\n");
                 ret = btrfs_extend_item(trans, root, path,
                                         sizeof(struct btrfs_csum_item));
                 BUG_ON(ret);
-printk("item extended\n");
                 goto csum;
         }
 
 insert:
         csum_offset = 0;
-printk("inserting item %Lu %Lu %u\n", file_key.objectid, file_key.offset, file_key.flags);
         ret = btrfs_insert_empty_item(trans, root, path, &file_key,
                                       sizeof(struct btrfs_csum_item));
         if (ret != 0 && ret != -EEXIST)
@@ -201,12 +181,10 @@ csum:
         item += csum_offset;
 found:
         ret = btrfs_csum_data(root, data, len, item->csum);
-        btrfs_set_csum_extent_offset(item, extent_offset);
         btrfs_mark_buffer_dirty(path->nodes[0]);
 fail:
         btrfs_release_path(root, path);
         btrfs_free_path(path);
-printk("return ret %d\n", ret);
         return ret;
 }
 
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 6a56416147e6..b2a2220d1352 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -524,7 +524,7 @@ static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
         int advance;
         unsigned char d_type = DT_UNKNOWN;
         int over = 0;
-        int key_type = BTRFS_DIR_INDEX_KEY;
+        int key_type = BTRFS_DIR_ITEM_KEY;
 
         /* FIXME, use a real flag for deciding about the key type */
         if (root->fs_info->tree_root == root)
@@ -561,9 +561,6 @@ static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
                 item = leaf->items + slot;
                 if (btrfs_disk_key_objectid(&item->key) != key.objectid)
                         break;
-                if (key_type == BTRFS_DIR_INDEX_KEY &&
-                    btrfs_disk_key_offset(&item->key) > root->highest_inode)
-                        break;
                 if (btrfs_disk_key_type(&item->key) != key_type)
                         continue;
                 if (btrfs_disk_key_offset(&item->key) < filp->f_pos)
@@ -1119,7 +1116,6 @@ allocate:
 out:
         btrfs_release_path(root, path);
         btrfs_free_path(path);
-printk("mapping iblock %lu to %lu\n", iblock, result->b_blocknr);
         if (trans)
                 btrfs_end_transaction(trans, root);
         return err;
@@ -1233,7 +1229,6 @@ static int dirty_and_release_pages(struct btrfs_trans_handle *trans,
                                    struct file *file,
                                    struct page **pages,
                                    size_t num_pages,
-                                   u64 extent_offset,
                                    loff_t pos,
                                    size_t write_bytes)
 {
@@ -1253,7 +1248,6 @@ static int dirty_and_release_pages(struct btrfs_trans_handle *trans,
                 trans = btrfs_start_transaction(root, 1);
                 btrfs_csum_file_block(trans, root, inode->i_ino,
                                       pages[i]->index << PAGE_CACHE_SHIFT,
-                                      extent_offset,
                                       kmap(pages[i]), PAGE_CACHE_SIZE);
                 kunmap(pages[i]);
                 SetPageChecked(pages[i]);
@@ -1275,86 +1269,6 @@ failed:
         return err;
 }
 
-static int drop_csums(struct btrfs_trans_handle *trans,
-                          struct btrfs_root *root,
-                          struct inode *inode,
-                          u64 start, u64 end)
-{
-        struct btrfs_path *path;
-        struct btrfs_leaf *leaf;
-        struct btrfs_key key;
-        int slot;
-        struct btrfs_csum_item *item;
-        char *old_block = NULL;
-        u64 cur = start;
-        u64 found_end;
-        u64 num_csums;
-        u64 item_size;
-        int ret;
-
-        path = btrfs_alloc_path();
-        if (!path)
-                return -ENOMEM;
-        while(cur < end) {
-                item = btrfs_lookup_csum(trans, root, path,
-                                         inode->i_ino, cur, 1);
-                if (IS_ERR(item)) {
-                        cur += root->blocksize;
-                        continue;
-                }
-                leaf = btrfs_buffer_leaf(path->nodes[0]);
-                slot = path->slots[0];
-                btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key);
-                item_size = btrfs_item_size(leaf->items + slot);
-                num_csums = item_size / sizeof(struct btrfs_csum_item);
-                found_end = key.offset + (num_csums << inode->i_blkbits);
-                cur = found_end;
-
-                if (found_end > end) {
-                        char *src;
-                        old_block = kmalloc(root->blocksize, GFP_NOFS);
-                        src = btrfs_item_ptr(leaf, slot, char);
-                        memcpy(old_block, src, item_size);
-                }
-                if (key.offset < start) {
-                        u64 new_size = (start - key.offset) >>
-                                        inode->i_blkbits;
-                        new_size *= sizeof(struct btrfs_csum_item);
-                        ret = btrfs_truncate_item(trans, root, path, new_size);
-                        BUG_ON(ret);
-                } else {
-                        btrfs_del_item(trans, root, path);
-                }
-                btrfs_release_path(root, path);
-                if (found_end > end) {
-                        char *dst;
-                        int i;
-                        int new_size;
-
-                        num_csums = (found_end - end) >> inode->i_blkbits;
-                        new_size = num_csums * sizeof(struct btrfs_csum_item);
-                        key.offset = end;
-                        ret = btrfs_insert_empty_item(trans, root, path,
-                                                      &key, new_size);
-                        BUG_ON(ret);
-                        dst = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
-                                             path->slots[0], char);
-                        memcpy(dst, old_block + item_size - new_size,
-                               new_size);
-                        item = (struct btrfs_csum_item *)dst;
-                        for (i = 0; i < num_csums; i++) {
-                                btrfs_set_csum_extent_offset(item, end);
-                                item++;
-                        }
-                        mark_buffer_dirty(path->nodes[0]);
-                        kfree(old_block);
-                        break;
-                }
-        }
-        btrfs_free_path(path);
-        return 0;
-}
-
 static int drop_extents(struct btrfs_trans_handle *trans,
                           struct btrfs_root *root,
                           struct inode *inode,
@@ -1376,12 +1290,16 @@ static int drop_extents(struct btrfs_trans_handle *trans,
         if (!path)
                 return -ENOMEM;
 search_again:
-printk("drop extent inode %lu start %Lu end %Lu\n", inode->i_ino, start, end);
         ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino,
                                        search_start, -1);
-        if (ret != 0) {
-printk("lookup failed\n");
+        if (ret < 0)
                 goto out;
+        if (ret > 0) {
+                if (path->slots[0] == 0) {
+                        ret = -ENOENT;
+                        goto out;
+                }
+                path->slots[0]--;
         }
         while(1) {
                 keep = 0;
@@ -1390,14 +1308,11 @@ printk("lookup failed\n");
                 slot = path->slots[0];
                 btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key);
 
-printk("found key %Lu %Lu %u\n", key.objectid, key.offset, key.flags);
-
                 extent = btrfs_item_ptr(leaf, slot,
                                         struct btrfs_file_extent_item);
                 extent_end = key.offset +
                         (btrfs_file_extent_num_blocks(extent) <<
                          inode->i_blkbits);
-printk("extent end is %Lu\n", extent_end);
                 if (key.offset >= end || key.objectid != inode->i_ino) {
                         ret = 0;
                         goto out;
@@ -1420,16 +1335,12 @@ printk("extent end is %Lu\n", extent_end);
                         keep = 1;
                         WARN_ON(start & (root->blocksize - 1));
                         new_num = (start - key.offset) >> inode->i_blkbits;
-printk("truncating existing extent, was %Lu ", btrfs_file_extent_num_blocks(extent));
                         btrfs_set_file_extent_num_blocks(extent, new_num);
-printk("now %Lu\n", btrfs_file_extent_num_blocks(extent));
-
                         mark_buffer_dirty(path->nodes[0]);
                 }
                 if (!keep) {
                         u64 disk_blocknr;
                         u64 disk_num_blocks;
-printk("del old\n");
                         disk_blocknr = btrfs_file_extent_disk_blocknr(extent);
                         disk_num_blocks =
                                 btrfs_file_extent_disk_num_blocks(extent);
@@ -1454,15 +1365,12 @@ printk("del old\n");
                 if (bookend) {
                         /* create bookend */
                         struct btrfs_key ins;
-printk("bookend! extent end %Lu\n", extent_end);
                         ins.objectid = inode->i_ino;
                         ins.offset = end;
                         ins.flags = 0;
                         btrfs_set_key_type(&ins, BTRFS_EXTENT_DATA_KEY);
 
                         btrfs_release_path(root, path);
-                        ret = drop_csums(trans, root, inode, start, end);
-                        BUG_ON(ret);
                         ret = btrfs_insert_empty_item(trans, root, path, &ins,
                                                       sizeof(*extent));
                         BUG_ON(ret);
@@ -1486,10 +1394,9 @@ printk("bookend! extent end %Lu\n", extent_end);
 
                         btrfs_set_file_extent_generation(extent,
                                     btrfs_file_extent_generation(&old));
-printk("new bookend at offset %Lu, file_extent_offset %Lu, file_extent_num_blocks %Lu\n", end, btrfs_file_extent_offset(extent), btrfs_file_extent_num_blocks(extent));
                         btrfs_mark_buffer_dirty(path->nodes[0]);
                         ret = 0;
-                        goto out_nocsum;
+                        goto out;
                 }
 next_leaf:
                 if (slot >= btrfs_header_nritems(&leaf->header) - 1) {
@@ -1504,10 +1411,6 @@ next_leaf:
         }
 
 out:
-        ret = drop_csums(trans, root, inode, start, end);
-        BUG_ON(ret);
-
-out_nocsum:
         btrfs_free_path(path);
         return ret;
 }
@@ -1556,7 +1459,6 @@ static int prepare_pages(struct btrfs_root *root,
                 head = page_buffers(pages[i]);
                 bh = head;
                 do {
-printk("mapping page %lu to block %Lu\n", pages[i]->index, alloc_extent_start);
                         err = btrfs_map_bh_to_logical(root, bh,
                                                       alloc_extent_start);
                         BUG_ON(err);
@@ -1597,7 +1499,6 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
         u64 start_pos;
         u64 num_blocks;
         u64 alloc_extent_start;
-        u64 orig_extent_start;
         struct btrfs_trans_handle *trans;
         struct btrfs_key ins;
 
@@ -1640,7 +1541,6 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
                                    (pos + count + root->blocksize -1) &
                                    ~(root->blocksize - 1));
         }
-        orig_extent_start = start_pos;
         ret = btrfs_alloc_extent(trans, root, num_blocks, 1,
                                  (u64)-1, &ins);
         BUG_ON(ret);
@@ -1656,7 +1556,6 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
                 size_t write_bytes = min(count, PAGE_CACHE_SIZE - offset);
                 size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >>
                                         PAGE_CACHE_SHIFT;
-printk("num_pages is %lu\n", num_pages);
 
                 memset(pages, 0, sizeof(pages));
                 ret = prepare_pages(root, file, pages, num_pages,
@@ -1670,10 +1569,8 @@ printk("num_pages is %lu\n", num_pages);
                                            write_bytes, pages, buf);
                 BUG_ON(ret);
 
-printk("2num_pages is %lu\n", num_pages);
                 ret = dirty_and_release_pages(NULL, root, file, pages,
-                                              num_pages, orig_extent_start,
-                                              pos, write_bytes);
+                                              num_pages, pos, write_bytes);
                 BUG_ON(ret);
                 btrfs_drop_pages(pages, num_pages);