/*
* Copyright (C) 2007 Oracle. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#include <linux/bio.h>
#include <linux/slab.h>
#include <linux/pagemap.h>
#include <linux/highmem.h>
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
#include "volumes.h"
#include "print-tree.h"
#define __MAX_CSUM_ITEMS(r, size) ((unsigned long)(((BTRFS_LEAF_DATA_SIZE(r) - \
sizeof(struct btrfs_item) * 2) / \
size) - 1))
#define MAX_CSUM_ITEMS(r, size) (min_t(u32, __MAX_CSUM_ITEMS(r, size), \
PAGE_CACHE_SIZE))
#define MAX_ORDERED_SUM_BYTES(r) ((PAGE_SIZE - \
sizeof(struct btrfs_ordered_sum)) / \
sizeof(u32) * (r)->sectorsize)
int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 objectid, u64 pos,
u64 disk_offset, u64 disk_num_bytes,
u64 num_bytes, u64 offset, u64 ram_bytes,
u8 compression, u8 encryption, u16 other_encoding)
{
int ret = 0;
struct btrfs_file_extent_item *item;
struct btrfs_key file_key;
struct btrfs_path *path;
struct extent_buffer *leaf;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
file_key.objectid = objectid;
file_key.offset = pos;
file_key.type = BTRFS_EXTENT_DATA_KEY;
path->leave_spinning = 1;
ret = btrfs_insert_empty_item(trans, root, path, &file_key,
sizeof(*item));
if (ret < 0)
goto out;
BUG_ON(ret); /* Can't happen */
leaf = path->nodes[0];
item = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_file_extent_item);
btrfs_set_file_extent_disk_bytenr(leaf, item, disk_offset);
btrfs_set_file_extent_disk_num_bytes(leaf, item, disk_num_bytes);
btrfs_set_file_extent_offset(leaf, item, offset);
btrfs_set_file_extent_num_bytes(leaf, item, num_bytes);
btrfs_set_file_extent_ram_bytes(leaf, item, ram_bytes);
btrfs_set_file_extent_generation(leaf, item, trans->transid);
btrfs_set_file_extent_type(leaf, item, BTRFS_FILE_EXTENT_REG);
btrfs_set_file_extent_compression(leaf, item, compression);
btrfs_set_file_extent_encryption(leaf, item, encryption);
btrfs_set_file_extent_other_encoding(leaf, item, other_encoding);
btrfs_mark_buffer_dirty(leaf);
out:
btrfs_free_path(path);
return ret;
}
static struct btrfs_csum_item *
btrfs_lookup_csum(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
u64 bytenr, int cow)
{
int ret;
struct btrfs_key file_key;
struct btrfs_key found_key;
struct btrfs_csum_item *item;
struct extent_buffer *leaf;
u64 csum_offset = 0;
u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
int csums_in_item;
file_key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
file_key.offset = bytenr;
file_key.type = BTRFS_EXTENT_CSUM_KEY;
ret = btrfs_search_slot(trans, root, &file_key, path, 0, cow);
if (ret < 0)
goto fail;
leaf = path->nodes[0];
if (ret > 0) {
ret = 1;
if (path->slots[0] == 0)
goto fail;
path->slots[0]--;
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
if (found_key.type != BTRFS_EXTENT_CSUM_KEY)
goto fail;
csum_offset = (bytenr - found_key.offset) >>
root->fs_info->sb->s_blocksize_bits;
csums_in_item = btrfs_item_size_nr(leaf, path->slots[0]);
csums_in_item /= csum_size;
if (csum_offset == csums_in_item) {
ret = -EFBIG;
goto fail;
} else if (csum_offset > csums_in_item) {
goto fail;
}
}
item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_csum_item);
item = (struct btrfs_csum_item *)((unsigned char *)item +
csum_offset * csum_size);
return item;
fail:
if (ret > 0)
ret = -ENOENT;
return ERR_PTR(ret);
}
int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path, u64 objectid,
u64 offset, int mod)
{
int ret;
struct btrfs_key file_key;
int ins_len = mod < 0 ? -1 : 0;
int cow = mod != 0;
file_key.objectid = objectid;
file_key.offset = offset;
file_key.type = BTRFS_EXTENT_DATA_KEY;
ret = btrfs_search_slot(trans, root, &file_key, path, ins_len, cow);
return ret;
}
static void btrfs_io_bio_endio_readpage(struct btrfs_io_bio *bio, int err)
{
kfree(bio->csum_allocated);
}
static int __btrfs_lookup_bio_sums(struct btrfs_root *root,
struct inode *inode, struct bio *bio,
u64 logical_offset, u32 *dst, int dio)
{
struct bio_vec *bvec = bio->bi_io_vec;
struct btrfs_io_bio *btrfs_bio = btrfs_io_bio(bio);
struct btrfs_csum_item *item = NULL;
struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
struct btrfs_path *path;
u8 *csum;
u64 offset = 0;
u64 item_start_offset = 0;
u64 item_last_offset = 0;
u64 disk_bytenr;
u32 diff;
int nblocks;
int bio_index = 0;
int count;
u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
nblocks = bio->bi_iter.bi_size >> inode->i_sb->s_blocksize_bits;
if (!dst) {
if (nblocks * csum_size > BTRFS_BIO_INLINE_CSUM_SIZE) {
btrfs_bio->csum_allocated = kmalloc(nblocks * csum_size,
GFP_NOFS);
if (!btrfs_bio->csum_allocated) {
btrfs_free_path(path);
return -ENOMEM;
}
btrfs_bio->csum = btrfs_bio->csum_allocated;
btrfs_bio->end_io = btrfs_io_bio_endio_readpage;
} else {
btrfs_bio->csum = btrfs_bio->csum_inline;
}
csum = btrfs_bio->csum;
} else {
csum = (u8 *)dst;
}
if (bio->bi_iter.bi_size > PAGE_CACHE_SIZE * 8)
path->reada = 2;
WARN_ON(bio->bi_vcnt <= 0);
/*
* the free space stuff is only read when it hasn't been
* updated in the current transaction. So, we can safely
* read from the commit root and sidestep a nasty deadlock
* between reading the free space cache and updating the csum tree.
*/
if (btrfs_is_free_space_inode(inode)) {
path->search_commit_root = 1;
path->skip_locking = 1;
}
disk_bytenr = (u64)bio->bi_iter.bi_sector << 9;
if (dio)
offset = logical_offset;
while (bio_index < bio->bi_vcnt) {
if (!dio)
offset = page_offset(bvec->bv_page) + bvec->bv_offset;
count = btrfs_find_ordered_sum(inode, offset, disk_bytenr,
(u32 *)csum, nblocks);
if (count)
goto found;
if (!item || disk_bytenr < item_start_offset ||
disk_bytenr >= item_last_offset) {
struct btrfs_key found_key;
u32 item_size;
if (item)
btrfs_release_path(path);
item = btrfs_lookup_csum(NULL, root->fs_info->csum_root,
path, disk_bytenr, 0);
if (IS_ERR(item)) {
count = 1;
memset(csum, 0, csum_size);
if (BTRFS_I(inode)->root->root_key.objectid ==
BTRFS_DATA_RELOC_TREE_OBJECTID) {
set_extent_bits(io_tree, offset,
offset + bvec->bv_len - 1,
EXTENT_NODATASUM, GFP_NOFS);
} else {
btrfs_info(BTRFS_I(inode)->root->fs_info,
"no csum found for inode %llu start %llu",
btrfs_ino(inode), offset);
}
item = NULL;
btrfs_release_path(path);
goto found;
}
btrfs_item_key_to_cpu(path->nodes[0], &found_key,
path->slots[0]);
item_start_offset = found_key.offset;
item_size = btrfs_item_size_nr(path->nodes[0],
path->slots[0]);
item_last_offset = item_start_offset +
(item_size / csum_size) *
root->sectorsize;
item = btrfs_item_ptr(path->nodes[0], path->slots[0],
struct btrfs_csum_item);
}
/*
* this byte range must be able to fit inside
* a single leaf so it will al