Commit dd137dd1 authored by Sweet Tea Dorminy's avatar Sweet Tea Dorminy Committed by David Sterba
Browse files

btrfs: factor out allocating an array of pages



Several functions currently populate an array of page pointers one
allocated page at a time. Factor out the common code so as to allow
improvements to all of the sites at once.

Reviewed-by: default avatarNikolay Borisov <nborisov@suse.com>
Signed-off-by: default avatarSweet Tea Dorminy <sweettea-kernel@dorminy.me>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 0d031dc4
Loading
Loading
Loading
Loading
+3 −5
Original line number Diff line number Diff line
@@ -1552,11 +1552,9 @@ static int btrfsic_read_block(struct btrfsic_state *state,
		return -ENOMEM;
	block_ctx->datav = block_ctx->mem_to_free;
	block_ctx->pagev = (struct page **)(block_ctx->datav + num_pages);
	for (i = 0; i < num_pages; i++) {
		block_ctx->pagev[i] = alloc_page(GFP_NOFS);
		if (!block_ctx->pagev[i])
			return -1;
	}
	ret = btrfs_alloc_page_array(num_pages, block_ctx->pagev);
	if (ret)
		return ret;

	dev_bytenr = block_ctx->dev_bytenr;
	for (i = 0; i < num_pages;) {
+15 −21
Original line number Diff line number Diff line
@@ -809,8 +809,6 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
	struct extent_map_tree *em_tree;
	struct compressed_bio *cb;
	unsigned int compressed_len;
	unsigned int nr_pages;
	unsigned int pg_index;
	struct bio *comp_bio = NULL;
	const u64 disk_bytenr = bio->bi_iter.bi_sector << SECTOR_SHIFT;
	u64 cur_disk_byte = disk_bytenr;
@@ -820,7 +818,8 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
	u64 em_start;
	struct extent_map *em;
	blk_status_t ret;
	int faili = 0;
	int ret2;
	int i;
	u8 *sums;

	em_tree = &BTRFS_I(inode)->extent_tree;
@@ -863,24 +862,18 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
	cb->compress_type = extent_compress_type(bio_flags);
	cb->orig_bio = bio;

	nr_pages = DIV_ROUND_UP(compressed_len, PAGE_SIZE);
	cb->compressed_pages = kcalloc(nr_pages, sizeof(struct page *),
				       GFP_NOFS);
	cb->nr_pages = DIV_ROUND_UP(compressed_len, PAGE_SIZE);
	cb->compressed_pages = kcalloc(cb->nr_pages, sizeof(struct page *), GFP_NOFS);
	if (!cb->compressed_pages) {
		ret = BLK_STS_RESOURCE;
		goto fail1;
		goto fail;
	}

	for (pg_index = 0; pg_index < nr_pages; pg_index++) {
		cb->compressed_pages[pg_index] = alloc_page(GFP_NOFS);
		if (!cb->compressed_pages[pg_index]) {
			faili = pg_index - 1;
	ret2 = btrfs_alloc_page_array(cb->nr_pages, cb->compressed_pages);
	if (ret2) {
		ret = BLK_STS_RESOURCE;
			goto fail2;
		}
		goto fail;
	}
	faili = nr_pages - 1;
	cb->nr_pages = nr_pages;

	add_ra_bio_pages(inode, em_start + em_len, cb);

@@ -957,14 +950,15 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
	}
	return BLK_STS_OK;

fail2:
	while (faili >= 0) {
		__free_page(cb->compressed_pages[faili]);
		faili--;
fail:
	if (cb->compressed_pages) {
		for (i = 0; i < cb->nr_pages; i++) {
			if (cb->compressed_pages[i])
				__free_page(cb->compressed_pages[i]);
		}
	}

	kfree(cb->compressed_pages);
fail1:
	kfree(cb);
out:
	free_extent_map(em);
+50 −16
Original line number Diff line number Diff line
@@ -3133,6 +3133,34 @@ static void end_bio_extent_readpage(struct bio *bio)
	bio_put(bio);
}

/**
 * Populate every free slot in a provided array with pages.
 *
 * @nr_pages:   number of pages to allocate
 * @page_array: the array to fill with pages; any existing non-null entries in
 * 		the array will be skipped
 *
 * Return: 0        if all pages were able to be allocated;
 *         -ENOMEM  otherwise, and the caller is responsible for freeing all
 *                  non-null page pointers in the array.
 */
int btrfs_alloc_page_array(unsigned int nr_pages, struct page **page_array)
{
	int i;

	for (i = 0; i < nr_pages; i++) {
		struct page *page;

		if (page_array[i])
			continue;
		page = alloc_page(GFP_NOFS);
		if (!page)
			return -ENOMEM;
		page_array[i] = page;
	}
	return 0;
}

/*
 * Initialize the members up to but not including 'bio'. Use after allocating a
 * new bio by bio_alloc_bioset as it does not initialize the bytes outside of
@@ -5912,9 +5940,9 @@ __alloc_extent_buffer(struct btrfs_fs_info *fs_info, u64 start,
struct extent_buffer *btrfs_clone_extent_buffer(const struct extent_buffer *src)
{
	int i;
	struct page *p;
	struct extent_buffer *new;
	int num_pages = num_extent_pages(src);
	int ret;

	new = __alloc_extent_buffer(src->fs_info, src->start, src->len);
	if (new == NULL)
@@ -5927,22 +5955,23 @@ struct extent_buffer *btrfs_clone_extent_buffer(const struct extent_buffer *src)
	 */
	set_bit(EXTENT_BUFFER_UNMAPPED, &new->bflags);

	for (i = 0; i < num_pages; i++) {
		int ret;

		p = alloc_page(GFP_NOFS);
		if (!p) {
	memset(new->pages, 0, sizeof(*new->pages) * num_pages);
	ret = btrfs_alloc_page_array(num_pages, new->pages);
	if (ret) {
		btrfs_release_extent_buffer(new);
		return NULL;
	}

	for (i = 0; i < num_pages; i++) {
		int ret;
		struct page *p = new->pages[i];

		ret = attach_extent_buffer_page(new, p, NULL);
		if (ret < 0) {
			put_page(p);
			btrfs_release_extent_buffer(new);
			return NULL;
		}
		WARN_ON(PageDirty(p));
		new->pages[i] = p;
		copy_page(page_address(p), page_address(src->pages[i]));
	}
	set_extent_buffer_uptodate(new);
@@ -5956,31 +5985,36 @@ struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
	struct extent_buffer *eb;
	int num_pages;
	int i;
	int ret;

	eb = __alloc_extent_buffer(fs_info, start, len);
	if (!eb)
		return NULL;

	num_pages = num_extent_pages(eb);
	ret = btrfs_alloc_page_array(num_pages, eb->pages);
	if (ret)
		goto err;

	for (i = 0; i < num_pages; i++) {
		int ret;
		struct page *p = eb->pages[i];

		eb->pages[i] = alloc_page(GFP_NOFS);
		if (!eb->pages[i])
			goto err;
		ret = attach_extent_buffer_page(eb, eb->pages[i], NULL);
		ret = attach_extent_buffer_page(eb, p, NULL);
		if (ret < 0)
			goto err;
	}

	set_extent_buffer_uptodate(eb);
	btrfs_set_header_nritems(eb, 0);
	set_bit(EXTENT_BUFFER_UNMAPPED, &eb->bflags);

	return eb;
err:
	for (; i > 0; i--) {
		detach_extent_buffer_page(eb, eb->pages[i - 1]);
		__free_page(eb->pages[i - 1]);
	for (i = 0; i < num_pages; i++) {
		if (eb->pages[i]) {
			detach_extent_buffer_page(eb, eb->pages[i]);
			__free_page(eb->pages[i]);
		}
	}
	__free_extent_buffer(eb);
	return NULL;
+2 −0
Original line number Diff line number Diff line
@@ -277,6 +277,8 @@ void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
void extent_clear_unlock_delalloc(struct btrfs_inode *inode, u64 start, u64 end,
				  struct page *locked_page,
				  u32 bits_to_clear, unsigned long page_ops);

int btrfs_alloc_page_array(unsigned int nr_pages, struct page **page_array);
struct bio *btrfs_bio_alloc(unsigned int nr_iovecs);
struct bio *btrfs_bio_clone(struct bio *bio);
struct bio *btrfs_bio_clone_partial(struct bio *orig, u64 offset, u64 size);
+4 −6
Original line number Diff line number Diff line
@@ -10461,13 +10461,11 @@ static ssize_t btrfs_encoded_read_regular(struct kiocb *iocb,
	pages = kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS);
	if (!pages)
		return -ENOMEM;
	for (i = 0; i < nr_pages; i++) {
		pages[i] = alloc_page(GFP_NOFS);
		if (!pages[i]) {
	ret = btrfs_alloc_page_array(nr_pages, pages);
	if (ret) {
		ret = -ENOMEM;
		goto out;
		}
	}

	ret = btrfs_encoded_read_regular_fill_pages(inode, start, disk_bytenr,
						    disk_io_size, pages);
Loading