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![Qu Wenruo](/assets/img/avatar_default.png)
To avoid name conflicting between the extent buffer based btrfs_path from btrfs-progs, rename struct btrfs_path to struct __btrfs_path. Also rename btrfs_free_path() to __btrfs_free_path() to avoid conflicts. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Marek Behún <marek.behun@nic.cz>
926 lines
21 KiB
C
926 lines
21 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* BTRFS filesystem implementation for U-Boot
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*
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* 2017 Marek Behun, CZ.NIC, marek.behun@nic.cz
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*/
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#include <linux/kernel.h>
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#include <linux/bug.h>
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#include <malloc.h>
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#include <memalign.h>
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#include "btrfs.h"
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#include "ctree.h"
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#include "extent-io.h"
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#include "disk-io.h"
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u64 btrfs_read_extent_inline(struct __btrfs_path *path,
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struct btrfs_file_extent_item *extent, u64 offset,
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u64 size, char *out)
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{
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u32 clen, dlen, orig_size = size, res;
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const char *cbuf;
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char *dbuf;
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const int data_off = offsetof(struct btrfs_file_extent_item,
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disk_bytenr);
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clen = btrfs_path_item_size(path) - data_off;
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cbuf = (const char *) extent + data_off;
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dlen = extent->ram_bytes;
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if (offset > dlen)
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return -1ULL;
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if (size > dlen - offset)
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size = dlen - offset;
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if (extent->compression == BTRFS_COMPRESS_NONE) {
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memcpy(out, cbuf + offset, size);
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return size;
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}
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if (dlen > orig_size) {
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dbuf = malloc(dlen);
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if (!dbuf)
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return -1ULL;
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} else {
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dbuf = out;
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}
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res = btrfs_decompress(extent->compression, cbuf, clen, dbuf, dlen);
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if (res == -1 || res != dlen)
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goto err;
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if (dlen > orig_size) {
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memcpy(out, dbuf + offset, size);
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free(dbuf);
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} else if (offset) {
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memmove(out, dbuf + offset, size);
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}
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return size;
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err:
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if (dlen > orig_size)
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free(dbuf);
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return -1ULL;
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}
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u64 btrfs_read_extent_reg(struct __btrfs_path *path,
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struct btrfs_file_extent_item *extent, u64 offset,
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u64 size, char *out)
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{
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u64 physical, clen, dlen, orig_size = size;
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u32 res;
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char *cbuf, *dbuf;
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clen = extent->disk_num_bytes;
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dlen = extent->num_bytes;
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if (offset > dlen)
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return -1ULL;
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if (size > dlen - offset)
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size = dlen - offset;
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/* sparse extent */
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if (extent->disk_bytenr == 0) {
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memset(out, 0, size);
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return size;
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}
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physical = btrfs_map_logical_to_physical(extent->disk_bytenr);
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if (physical == -1ULL)
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return -1ULL;
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if (extent->compression == BTRFS_COMPRESS_NONE) {
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physical += extent->offset + offset;
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if (!btrfs_devread(physical, size, out))
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return -1ULL;
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return size;
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}
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cbuf = malloc_cache_aligned(dlen > size ? clen + dlen : clen);
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if (!cbuf)
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return -1ULL;
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if (dlen > orig_size)
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dbuf = cbuf + clen;
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else
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dbuf = out;
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if (!btrfs_devread(physical, clen, cbuf))
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goto err;
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res = btrfs_decompress(extent->compression, cbuf, clen, dbuf, dlen);
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if (res == -1)
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goto err;
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if (dlen > orig_size)
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memcpy(out, dbuf + offset, size);
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else
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memmove(out, dbuf + offset, size);
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free(cbuf);
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return res;
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err:
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free(cbuf);
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return -1ULL;
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}
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void extent_io_tree_init(struct extent_io_tree *tree)
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{
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cache_tree_init(&tree->state);
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cache_tree_init(&tree->cache);
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tree->cache_size = 0;
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}
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static struct extent_state *alloc_extent_state(void)
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{
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struct extent_state *state;
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state = malloc(sizeof(*state));
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if (!state)
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return NULL;
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state->cache_node.objectid = 0;
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state->refs = 1;
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state->state = 0;
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state->xprivate = 0;
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return state;
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}
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static void btrfs_free_extent_state(struct extent_state *state)
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{
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state->refs--;
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BUG_ON(state->refs < 0);
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if (state->refs == 0)
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free(state);
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}
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static void free_extent_state_func(struct cache_extent *cache)
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{
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struct extent_state *es;
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es = container_of(cache, struct extent_state, cache_node);
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btrfs_free_extent_state(es);
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}
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static void free_extent_buffer_final(struct extent_buffer *eb);
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void extent_io_tree_cleanup(struct extent_io_tree *tree)
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{
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cache_tree_free_extents(&tree->state, free_extent_state_func);
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}
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static inline void update_extent_state(struct extent_state *state)
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{
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state->cache_node.start = state->start;
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state->cache_node.size = state->end + 1 - state->start;
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}
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/*
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* Utility function to look for merge candidates inside a given range.
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* Any extents with matching state are merged together into a single
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* extent in the tree. Extents with EXTENT_IO in their state field are
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* not merged
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*/
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static int merge_state(struct extent_io_tree *tree,
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struct extent_state *state)
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{
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struct extent_state *other;
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struct cache_extent *other_node;
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if (state->state & EXTENT_IOBITS)
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return 0;
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other_node = prev_cache_extent(&state->cache_node);
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if (other_node) {
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other = container_of(other_node, struct extent_state,
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cache_node);
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if (other->end == state->start - 1 &&
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other->state == state->state) {
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state->start = other->start;
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update_extent_state(state);
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remove_cache_extent(&tree->state, &other->cache_node);
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btrfs_free_extent_state(other);
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}
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}
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other_node = next_cache_extent(&state->cache_node);
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if (other_node) {
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other = container_of(other_node, struct extent_state,
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cache_node);
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if (other->start == state->end + 1 &&
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other->state == state->state) {
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other->start = state->start;
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update_extent_state(other);
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remove_cache_extent(&tree->state, &state->cache_node);
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btrfs_free_extent_state(state);
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}
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}
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return 0;
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}
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/*
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* insert an extent_state struct into the tree. 'bits' are set on the
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* struct before it is inserted.
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*/
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static int insert_state(struct extent_io_tree *tree,
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struct extent_state *state, u64 start, u64 end,
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int bits)
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{
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int ret;
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BUG_ON(end < start);
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state->state |= bits;
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state->start = start;
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state->end = end;
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update_extent_state(state);
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ret = insert_cache_extent(&tree->state, &state->cache_node);
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BUG_ON(ret);
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merge_state(tree, state);
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return 0;
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}
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/*
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* split a given extent state struct in two, inserting the preallocated
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* struct 'prealloc' as the newly created second half. 'split' indicates an
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* offset inside 'orig' where it should be split.
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*/
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static int split_state(struct extent_io_tree *tree, struct extent_state *orig,
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struct extent_state *prealloc, u64 split)
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{
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int ret;
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prealloc->start = orig->start;
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prealloc->end = split - 1;
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prealloc->state = orig->state;
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update_extent_state(prealloc);
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orig->start = split;
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update_extent_state(orig);
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ret = insert_cache_extent(&tree->state, &prealloc->cache_node);
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BUG_ON(ret);
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return 0;
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}
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/*
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* clear some bits on a range in the tree.
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*/
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static int clear_state_bit(struct extent_io_tree *tree,
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struct extent_state *state, int bits)
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{
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int ret = state->state & bits;
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state->state &= ~bits;
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if (state->state == 0) {
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remove_cache_extent(&tree->state, &state->cache_node);
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btrfs_free_extent_state(state);
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} else {
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merge_state(tree, state);
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}
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return ret;
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}
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/*
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* extent_buffer_bitmap_set - set an area of a bitmap
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* @eb: the extent buffer
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* @start: offset of the bitmap item in the extent buffer
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* @pos: bit number of the first bit
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* @len: number of bits to set
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*/
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void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start,
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unsigned long pos, unsigned long len)
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{
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u8 *p = (u8 *)eb->data + start + BIT_BYTE(pos);
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const unsigned int size = pos + len;
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int bits_to_set = BITS_PER_BYTE - (pos % BITS_PER_BYTE);
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u8 mask_to_set = BITMAP_FIRST_BYTE_MASK(pos);
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while (len >= bits_to_set) {
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*p |= mask_to_set;
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len -= bits_to_set;
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bits_to_set = BITS_PER_BYTE;
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mask_to_set = ~0;
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p++;
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}
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if (len) {
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mask_to_set &= BITMAP_LAST_BYTE_MASK(size);
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*p |= mask_to_set;
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}
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}
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/*
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* extent_buffer_bitmap_clear - clear an area of a bitmap
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* @eb: the extent buffer
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* @start: offset of the bitmap item in the extent buffer
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* @pos: bit number of the first bit
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* @len: number of bits to clear
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*/
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void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start,
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unsigned long pos, unsigned long len)
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{
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u8 *p = (u8 *)eb->data + start + BIT_BYTE(pos);
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const unsigned int size = pos + len;
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int bits_to_clear = BITS_PER_BYTE - (pos % BITS_PER_BYTE);
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u8 mask_to_clear = BITMAP_FIRST_BYTE_MASK(pos);
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while (len >= bits_to_clear) {
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*p &= ~mask_to_clear;
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len -= bits_to_clear;
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bits_to_clear = BITS_PER_BYTE;
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mask_to_clear = ~0;
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p++;
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}
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if (len) {
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mask_to_clear &= BITMAP_LAST_BYTE_MASK(size);
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*p &= ~mask_to_clear;
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}
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}
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/*
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* clear some bits on a range in the tree.
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*/
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int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, int bits)
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{
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struct extent_state *state;
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struct extent_state *prealloc = NULL;
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struct cache_extent *node;
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u64 last_end;
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int err;
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int set = 0;
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again:
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if (!prealloc) {
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prealloc = alloc_extent_state();
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if (!prealloc)
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return -ENOMEM;
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}
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/*
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* this search will find the extents that end after
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* our range starts
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*/
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node = search_cache_extent(&tree->state, start);
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if (!node)
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goto out;
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state = container_of(node, struct extent_state, cache_node);
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if (state->start > end)
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goto out;
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last_end = state->end;
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/*
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* | ---- desired range ---- |
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* | state | or
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* | ------------- state -------------- |
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*
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* We need to split the extent we found, and may flip
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* bits on second half.
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*
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* If the extent we found extends past our range, we
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* just split and search again. It'll get split again
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* the next time though.
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*
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* If the extent we found is inside our range, we clear
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* the desired bit on it.
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*/
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if (state->start < start) {
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err = split_state(tree, state, prealloc, start);
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BUG_ON(err == -EEXIST);
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prealloc = NULL;
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if (err)
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goto out;
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if (state->end <= end) {
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set |= clear_state_bit(tree, state, bits);
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if (last_end == (u64)-1)
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goto out;
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start = last_end + 1;
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} else {
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start = state->start;
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}
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goto search_again;
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}
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/*
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* | ---- desired range ---- |
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* | state |
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* We need to split the extent, and clear the bit
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* on the first half
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*/
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if (state->start <= end && state->end > end) {
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err = split_state(tree, state, prealloc, end + 1);
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BUG_ON(err == -EEXIST);
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set |= clear_state_bit(tree, prealloc, bits);
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prealloc = NULL;
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goto out;
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}
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start = state->end + 1;
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set |= clear_state_bit(tree, state, bits);
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if (last_end == (u64)-1)
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goto out;
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start = last_end + 1;
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goto search_again;
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out:
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if (prealloc)
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btrfs_free_extent_state(prealloc);
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return set;
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search_again:
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if (start > end)
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goto out;
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goto again;
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}
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/*
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* set some bits on a range in the tree.
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*/
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int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, int bits)
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{
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struct extent_state *state;
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struct extent_state *prealloc = NULL;
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struct cache_extent *node;
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int err = 0;
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u64 last_start;
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u64 last_end;
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again:
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if (!prealloc) {
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prealloc = alloc_extent_state();
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if (!prealloc)
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return -ENOMEM;
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}
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|
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/*
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* this search will find the extents that end after
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* our range starts
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*/
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node = search_cache_extent(&tree->state, start);
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if (!node) {
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err = insert_state(tree, prealloc, start, end, bits);
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BUG_ON(err == -EEXIST);
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prealloc = NULL;
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goto out;
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}
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state = container_of(node, struct extent_state, cache_node);
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last_start = state->start;
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last_end = state->end;
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|
|
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/*
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* | ---- desired range ---- |
|
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* | state |
|
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*
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* Just lock what we found and keep going
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*/
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if (state->start == start && state->end <= end) {
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state->state |= bits;
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merge_state(tree, state);
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if (last_end == (u64)-1)
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goto out;
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start = last_end + 1;
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goto search_again;
|
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}
|
|
/*
|
|
* | ---- desired range ---- |
|
|
* | state |
|
|
* or
|
|
* | ------------- state -------------- |
|
|
*
|
|
* We need to split the extent we found, and may flip bits on
|
|
* second half.
|
|
*
|
|
* If the extent we found extends past our
|
|
* range, we just split and search again. It'll get split
|
|
* again the next time though.
|
|
*
|
|
* If the extent we found is inside our range, we set the
|
|
* desired bit on it.
|
|
*/
|
|
if (state->start < start) {
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err = split_state(tree, state, prealloc, start);
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BUG_ON(err == -EEXIST);
|
|
prealloc = NULL;
|
|
if (err)
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|
goto out;
|
|
if (state->end <= end) {
|
|
state->state |= bits;
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|
start = state->end + 1;
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|
merge_state(tree, state);
|
|
if (last_end == (u64)-1)
|
|
goto out;
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|
start = last_end + 1;
|
|
} else {
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|
start = state->start;
|
|
}
|
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goto search_again;
|
|
}
|
|
/*
|
|
* | ---- desired range ---- |
|
|
* | state | or | state |
|
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*
|
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* There's a hole, we need to insert something in it and
|
|
* ignore the extent we found.
|
|
*/
|
|
if (state->start > start) {
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|
u64 this_end;
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|
if (end < last_start)
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|
this_end = end;
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|
else
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this_end = last_start -1;
|
|
err = insert_state(tree, prealloc, start, this_end,
|
|
bits);
|
|
BUG_ON(err == -EEXIST);
|
|
prealloc = NULL;
|
|
if (err)
|
|
goto out;
|
|
start = this_end + 1;
|
|
goto search_again;
|
|
}
|
|
/*
|
|
* | ---- desired range ---- |
|
|
* | ---------- state ---------- |
|
|
* We need to split the extent, and set the bit
|
|
* on the first half
|
|
*/
|
|
err = split_state(tree, state, prealloc, end + 1);
|
|
BUG_ON(err == -EEXIST);
|
|
|
|
state->state |= bits;
|
|
merge_state(tree, prealloc);
|
|
prealloc = NULL;
|
|
out:
|
|
if (prealloc)
|
|
btrfs_free_extent_state(prealloc);
|
|
return err;
|
|
search_again:
|
|
if (start > end)
|
|
goto out;
|
|
goto again;
|
|
}
|
|
|
|
int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end)
|
|
{
|
|
return set_extent_bits(tree, start, end, EXTENT_DIRTY);
|
|
}
|
|
|
|
int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end)
|
|
{
|
|
return clear_extent_bits(tree, start, end, EXTENT_DIRTY);
|
|
}
|
|
|
|
int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
|
|
u64 *start_ret, u64 *end_ret, int bits)
|
|
{
|
|
struct cache_extent *node;
|
|
struct extent_state *state;
|
|
int ret = 1;
|
|
|
|
/*
|
|
* this search will find all the extents that end after
|
|
* our range starts.
|
|
*/
|
|
node = search_cache_extent(&tree->state, start);
|
|
if (!node)
|
|
goto out;
|
|
|
|
while(1) {
|
|
state = container_of(node, struct extent_state, cache_node);
|
|
if (state->end >= start && (state->state & bits)) {
|
|
*start_ret = state->start;
|
|
*end_ret = state->end;
|
|
ret = 0;
|
|
break;
|
|
}
|
|
node = next_cache_extent(node);
|
|
if (!node)
|
|
break;
|
|
}
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
|
|
int bits, int filled)
|
|
{
|
|
struct extent_state *state = NULL;
|
|
struct cache_extent *node;
|
|
int bitset = 0;
|
|
|
|
node = search_cache_extent(&tree->state, start);
|
|
while (node && start <= end) {
|
|
state = container_of(node, struct extent_state, cache_node);
|
|
|
|
if (filled && state->start > start) {
|
|
bitset = 0;
|
|
break;
|
|
}
|
|
if (state->start > end)
|
|
break;
|
|
if (state->state & bits) {
|
|
bitset = 1;
|
|
if (!filled)
|
|
break;
|
|
} else if (filled) {
|
|
bitset = 0;
|
|
break;
|
|
}
|
|
start = state->end + 1;
|
|
if (start > end)
|
|
break;
|
|
node = next_cache_extent(node);
|
|
if (!node) {
|
|
if (filled)
|
|
bitset = 0;
|
|
break;
|
|
}
|
|
}
|
|
return bitset;
|
|
}
|
|
|
|
int set_state_private(struct extent_io_tree *tree, u64 start, u64 private)
|
|
{
|
|
struct cache_extent *node;
|
|
struct extent_state *state;
|
|
int ret = 0;
|
|
|
|
node = search_cache_extent(&tree->state, start);
|
|
if (!node) {
|
|
ret = -ENOENT;
|
|
goto out;
|
|
}
|
|
state = container_of(node, struct extent_state, cache_node);
|
|
if (state->start != start) {
|
|
ret = -ENOENT;
|
|
goto out;
|
|
}
|
|
state->xprivate = private;
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private)
|
|
{
|
|
struct cache_extent *node;
|
|
struct extent_state *state;
|
|
int ret = 0;
|
|
|
|
node = search_cache_extent(&tree->state, start);
|
|
if (!node) {
|
|
ret = -ENOENT;
|
|
goto out;
|
|
}
|
|
state = container_of(node, struct extent_state, cache_node);
|
|
if (state->start != start) {
|
|
ret = -ENOENT;
|
|
goto out;
|
|
}
|
|
*private = state->xprivate;
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
static struct extent_buffer *__alloc_extent_buffer(struct btrfs_fs_info *info,
|
|
u64 bytenr, u32 blocksize)
|
|
{
|
|
struct extent_buffer *eb;
|
|
|
|
eb = calloc(1, sizeof(struct extent_buffer));
|
|
if (!eb)
|
|
return NULL;
|
|
eb->data = malloc_cache_aligned(blocksize);
|
|
if (!eb->data) {
|
|
free(eb);
|
|
return NULL;
|
|
}
|
|
|
|
eb->start = bytenr;
|
|
eb->len = blocksize;
|
|
eb->refs = 1;
|
|
eb->flags = 0;
|
|
eb->cache_node.start = bytenr;
|
|
eb->cache_node.size = blocksize;
|
|
eb->fs_info = info;
|
|
memset_extent_buffer(eb, 0, 0, blocksize);
|
|
|
|
return eb;
|
|
}
|
|
|
|
struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src)
|
|
{
|
|
struct extent_buffer *new;
|
|
|
|
new = __alloc_extent_buffer(src->fs_info, src->start, src->len);
|
|
if (!new)
|
|
return NULL;
|
|
|
|
copy_extent_buffer(new, src, 0, 0, src->len);
|
|
new->flags |= EXTENT_BUFFER_DUMMY;
|
|
|
|
return new;
|
|
}
|
|
|
|
static void free_extent_buffer_final(struct extent_buffer *eb)
|
|
{
|
|
BUG_ON(eb->refs);
|
|
if (!(eb->flags & EXTENT_BUFFER_DUMMY)) {
|
|
struct extent_io_tree *tree = &eb->fs_info->extent_cache;
|
|
|
|
remove_cache_extent(&tree->cache, &eb->cache_node);
|
|
BUG_ON(tree->cache_size < eb->len);
|
|
tree->cache_size -= eb->len;
|
|
}
|
|
free(eb->data);
|
|
free(eb);
|
|
}
|
|
|
|
static void free_extent_buffer_internal(struct extent_buffer *eb, bool free_now)
|
|
{
|
|
if (!eb || IS_ERR(eb))
|
|
return;
|
|
|
|
eb->refs--;
|
|
BUG_ON(eb->refs < 0);
|
|
if (eb->refs == 0) {
|
|
if (eb->flags & EXTENT_DIRTY) {
|
|
error(
|
|
"dirty eb leak (aborted trans): start %llu len %u",
|
|
eb->start, eb->len);
|
|
}
|
|
if (eb->flags & EXTENT_BUFFER_DUMMY || free_now)
|
|
free_extent_buffer_final(eb);
|
|
}
|
|
}
|
|
|
|
void free_extent_buffer(struct extent_buffer *eb)
|
|
{
|
|
free_extent_buffer_internal(eb, 1);
|
|
}
|
|
|
|
struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree,
|
|
u64 bytenr, u32 blocksize)
|
|
{
|
|
struct extent_buffer *eb = NULL;
|
|
struct cache_extent *cache;
|
|
|
|
cache = lookup_cache_extent(&tree->cache, bytenr, blocksize);
|
|
if (cache && cache->start == bytenr &&
|
|
cache->size == blocksize) {
|
|
eb = container_of(cache, struct extent_buffer, cache_node);
|
|
eb->refs++;
|
|
}
|
|
return eb;
|
|
}
|
|
|
|
struct extent_buffer *find_first_extent_buffer(struct extent_io_tree *tree,
|
|
u64 start)
|
|
{
|
|
struct extent_buffer *eb = NULL;
|
|
struct cache_extent *cache;
|
|
|
|
cache = search_cache_extent(&tree->cache, start);
|
|
if (cache) {
|
|
eb = container_of(cache, struct extent_buffer, cache_node);
|
|
eb->refs++;
|
|
}
|
|
return eb;
|
|
}
|
|
|
|
struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
|
|
u64 bytenr, u32 blocksize)
|
|
{
|
|
struct extent_buffer *eb;
|
|
struct extent_io_tree *tree = &fs_info->extent_cache;
|
|
struct cache_extent *cache;
|
|
|
|
cache = lookup_cache_extent(&tree->cache, bytenr, blocksize);
|
|
if (cache && cache->start == bytenr &&
|
|
cache->size == blocksize) {
|
|
eb = container_of(cache, struct extent_buffer, cache_node);
|
|
eb->refs++;
|
|
} else {
|
|
int ret;
|
|
|
|
if (cache) {
|
|
eb = container_of(cache, struct extent_buffer,
|
|
cache_node);
|
|
free_extent_buffer(eb);
|
|
}
|
|
eb = __alloc_extent_buffer(fs_info, bytenr, blocksize);
|
|
if (!eb)
|
|
return NULL;
|
|
ret = insert_cache_extent(&tree->cache, &eb->cache_node);
|
|
if (ret) {
|
|
free(eb);
|
|
return NULL;
|
|
}
|
|
tree->cache_size += blocksize;
|
|
}
|
|
return eb;
|
|
}
|
|
|
|
/*
|
|
* Allocate a dummy extent buffer which won't be inserted into extent buffer
|
|
* cache.
|
|
*
|
|
* This mostly allows super block read write using existing eb infrastructure
|
|
* without pulluting the eb cache.
|
|
*
|
|
* This is especially important to avoid injecting eb->start == SZ_64K, as
|
|
* fuzzed image could have invalid tree bytenr covers super block range,
|
|
* and cause ref count underflow.
|
|
*/
|
|
struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
|
|
u64 bytenr, u32 blocksize)
|
|
{
|
|
struct extent_buffer *ret;
|
|
|
|
ret = __alloc_extent_buffer(fs_info, bytenr, blocksize);
|
|
if (!ret)
|
|
return NULL;
|
|
|
|
ret->flags |= EXTENT_BUFFER_DUMMY;
|
|
|
|
return ret;
|
|
}
|
|
|
|
int read_extent_from_disk(struct blk_desc *desc, struct disk_partition *part,
|
|
u64 physical, struct extent_buffer *eb,
|
|
unsigned long offset, unsigned long len)
|
|
{
|
|
int ret;
|
|
|
|
ret = __btrfs_devread(desc, part, eb->data + offset, len, physical);
|
|
if (ret < 0)
|
|
goto out;
|
|
if (ret != len) {
|
|
ret = -EIO;
|
|
goto out;
|
|
}
|
|
ret = 0;
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv,
|
|
unsigned long start, unsigned long len)
|
|
{
|
|
return memcmp(eb->data + start, ptrv, len);
|
|
}
|
|
|
|
void read_extent_buffer(const struct extent_buffer *eb, void *dst,
|
|
unsigned long start, unsigned long len)
|
|
{
|
|
memcpy(dst, eb->data + start, len);
|
|
}
|
|
|
|
void write_extent_buffer(struct extent_buffer *eb, const void *src,
|
|
unsigned long start, unsigned long len)
|
|
{
|
|
memcpy(eb->data + start, src, len);
|
|
}
|
|
|
|
void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
|
|
unsigned long dst_offset, unsigned long src_offset,
|
|
unsigned long len)
|
|
{
|
|
memcpy(dst->data + dst_offset, src->data + src_offset, len);
|
|
}
|
|
|
|
void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
|
|
unsigned long src_offset, unsigned long len)
|
|
{
|
|
memmove(dst->data + dst_offset, dst->data + src_offset, len);
|
|
}
|
|
|
|
void memset_extent_buffer(struct extent_buffer *eb, char c,
|
|
unsigned long start, unsigned long len)
|
|
{
|
|
memset(eb->data + start, c, len);
|
|
}
|
|
|
|
int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start,
|
|
unsigned long nr)
|
|
{
|
|
return le_test_bit(nr, (u8 *)eb->data + start);
|
|
}
|
|
|
|
int set_extent_buffer_dirty(struct extent_buffer *eb)
|
|
{
|
|
struct extent_io_tree *tree = &eb->fs_info->extent_cache;
|
|
if (!(eb->flags & EXTENT_DIRTY)) {
|
|
eb->flags |= EXTENT_DIRTY;
|
|
set_extent_dirty(tree, eb->start, eb->start + eb->len - 1);
|
|
extent_buffer_get(eb);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
int clear_extent_buffer_dirty(struct extent_buffer *eb)
|
|
{
|
|
struct extent_io_tree *tree = &eb->fs_info->extent_cache;
|
|
if (eb->flags & EXTENT_DIRTY) {
|
|
eb->flags &= ~EXTENT_DIRTY;
|
|
clear_extent_dirty(tree, eb->start, eb->start + eb->len - 1);
|
|
free_extent_buffer(eb);
|
|
}
|
|
return 0;
|
|
}
|