Commit 6f9994db authored by Liu Bo's avatar Liu Bo Committed by David Sterba
Browse files

Btrfs: create a helper to create em for IO 



We have similar codes to create and insert extent mapping around IO path,
this merges them into a single helper.

Signed-off-by: default avatarLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 4136135b

fs/btrfs/inode.c

+74 −115
Original line number Diff line number Diff line
@@ -109,10 +109,10 @@ static noinline int cow_file_range(struct inode *inode, 
				   u64 start, u64 end, u64 delalloc_end,

				   int *page_started, unsigned long *nr_written,

				   int unlock, struct btrfs_dedupe_hash *hash);

static struct extent_map *create_pinned_em(struct inode *inode, u64 start,

					   u64 len, u64 orig_start,

					   u64 block_start, u64 block_len,

					   u64 orig_block_len, u64 ram_bytes,

static struct extent_map *create_io_em(struct inode *inode, u64 start, u64 len,

				       u64 orig_start, u64 block_start,

				       u64 block_len, u64 orig_block_len,

				       u64 ram_bytes, int compress_type,

				       int type);



static int btrfs_dirty_inode(struct inode *inode);
@@ -697,7 +697,6 @@ static noinline void submit_compressed_extents(struct inode *inode, 
	struct btrfs_key ins;

	struct extent_map *em;

	struct btrfs_root *root = BTRFS_I(inode)->root;

	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;

	struct extent_io_tree *io_tree;

	int ret = 0;
@@ -785,46 +784,19 @@ static noinline void submit_compressed_extents(struct inode *inode, 
		 * here we're doing allocation and writeback of the

		 * compressed pages

		 */

		btrfs_drop_extent_cache(inode, async_extent->start,

					async_extent->start +

					async_extent->ram_size - 1, 0);



		em = alloc_extent_map();

		if (!em) {

			ret = -ENOMEM;

		em = create_io_em(inode, async_extent->start,

				  async_extent->ram_size, /* len */

				  async_extent->start, /* orig_start */

				  ins.objectid, /* block_start */

				  ins.offset, /* block_len */

				  ins.offset, /* orig_block_len */

				  async_extent->ram_size, /* ram_bytes */

				  async_extent->compress_type,

				  BTRFS_ORDERED_COMPRESSED);

		if (IS_ERR(em))

			/* ret value is not necessary due to void function */

			goto out_free_reserve;

		}

		em->start = async_extent->start;

		em->len = async_extent->ram_size;

		em->orig_start = em->start;

		em->mod_start = em->start;

		em->mod_len = em->len;



		em->block_start = ins.objectid;

		em->block_len = ins.offset;

		em->orig_block_len = ins.offset;

		em->ram_bytes = async_extent->ram_size;

		em->bdev = fs_info->fs_devices->latest_bdev;

		em->compress_type = async_extent->compress_type;

		set_bit(EXTENT_FLAG_PINNED, &em->flags);

		set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);

		em->generation = -1;



		while (1) {

			write_lock(&em_tree->lock);

			ret = add_extent_mapping(em_tree, em, 1);

			write_unlock(&em_tree->lock);

			if (ret != -EEXIST) {

		free_extent_map(em);

				break;

			}

			btrfs_drop_extent_cache(inode, async_extent->start,

						async_extent->start +

						async_extent->ram_size - 1, 0);

		}



		if (ret)

			goto out_free_reserve;



		ret = btrfs_add_ordered_extent_compress(inode,

						async_extent->start,
@@ -959,7 +931,6 @@ static noinline int cow_file_range(struct inode *inode, 
	u64 blocksize = fs_info->sectorsize;

	struct btrfs_key ins;

	struct extent_map *em;

	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;

	int ret = 0;



	if (btrfs_is_free_space_inode(inode)) {
@@ -1012,39 +983,18 @@ static noinline int cow_file_range(struct inode *inode, 
		if (ret < 0)

			goto out_unlock;



		em = alloc_extent_map();

		if (!em) {

			ret = -ENOMEM;

			goto out_reserve;

		}

		em->start = start;

		em->orig_start = em->start;

		ram_size = ins.offset;

		em->len = ins.offset;

		em->mod_start = em->start;

		em->mod_len = em->len;



		em->block_start = ins.objectid;

		em->block_len = ins.offset;

		em->orig_block_len = ins.offset;

		em->ram_bytes = ram_size;

		em->bdev = fs_info->fs_devices->latest_bdev;

		set_bit(EXTENT_FLAG_PINNED, &em->flags);

		em->generation = -1;



		while (1) {

			write_lock(&em_tree->lock);

			ret = add_extent_mapping(em_tree, em, 1);

			write_unlock(&em_tree->lock);

			if (ret != -EEXIST) {

				free_extent_map(em);

				break;

			}

			btrfs_drop_extent_cache(inode, start,

						start + ram_size - 1, 0);

		}

		if (ret)

		em = create_io_em(inode, start, ins.offset, /* len */

				  start, /* orig_start */

				  ins.objectid, /* block_start */

				  ins.offset, /* block_len */

				  ins.offset, /* orig_block_len */

				  ram_size, /* ram_bytes */

				  BTRFS_COMPRESS_NONE, /* compress_type */

				  0 /* type */);

		if (IS_ERR(em))

			goto out_reserve;

		free_extent_map(em);



		cur_alloc_size = ins.offset;

		ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
@@ -1251,6 +1201,7 @@ static noinline int run_delalloc_nocow(struct inode *inode, 
	struct btrfs_path *path;

	struct btrfs_file_extent_item *fi;

	struct btrfs_key found_key;

	struct extent_map *em;

	u64 cow_start;

	u64 cur_offset;

	u64 extent_end;
@@ -1431,35 +1382,28 @@ static noinline int run_delalloc_nocow(struct inode *inode, 
		}



		if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {

			struct extent_map *em;

			struct extent_map_tree *em_tree;

			em_tree = &BTRFS_I(inode)->extent_tree;

			em = alloc_extent_map();

			BUG_ON(!em); /* -ENOMEM */

			em->start = cur_offset;

			em->orig_start = found_key.offset - extent_offset;

			em->len = num_bytes;

			em->block_len = num_bytes;

			em->block_start = disk_bytenr;

			em->orig_block_len = disk_num_bytes;

			em->ram_bytes = ram_bytes;

			em->bdev = fs_info->fs_devices->latest_bdev;

			em->mod_start = em->start;

			em->mod_len = em->len;

			set_bit(EXTENT_FLAG_PINNED, &em->flags);

			set_bit(EXTENT_FLAG_FILLING, &em->flags);

			em->generation = -1;

			while (1) {

				write_lock(&em_tree->lock);

				ret = add_extent_mapping(em_tree, em, 1);

				write_unlock(&em_tree->lock);

				if (ret != -EEXIST) {

					free_extent_map(em);

					break;

			u64 orig_start = found_key.offset - extent_offset;



			em = create_io_em(inode, cur_offset, num_bytes,

					  orig_start,

					  disk_bytenr, /* block_start */

					  num_bytes, /* block_len */

					  disk_num_bytes, /* orig_block_len */

					  ram_bytes, BTRFS_COMPRESS_NONE,

					  BTRFS_ORDERED_PREALLOC);

			if (IS_ERR(em)) {

				if (!nolock && nocow)

					btrfs_end_write_no_snapshoting(root);

				if (nocow)

					btrfs_dec_nocow_writers(fs_info,

								disk_bytenr);

				ret = PTR_ERR(em);

				goto error;

			}

				btrfs_drop_extent_cache(inode, em->start,

						em->start + em->len - 1, 0);

			free_extent_map(em);

		}



		if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {

			type = BTRFS_ORDERED_PREALLOC;

		} else {

			type = BTRFS_ORDERED_NOCOW;
@@ -7207,9 +7151,11 @@ static struct extent_map *btrfs_create_dio_extent(struct inode *inode, 
	int ret;



	if (type != BTRFS_ORDERED_NOCOW) {

		em = create_pinned_em(inode, start, len, orig_start,

		em = create_io_em(inode, start, len, orig_start,

				  block_start, block_len, orig_block_len,

				      ram_bytes, type);

				  ram_bytes,

				  BTRFS_COMPRESS_NONE, /* compress_type */

				  type);

		if (IS_ERR(em))

			goto out;

	}
@@ -7545,10 +7491,11 @@ static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend, 
	return ret;

}



static struct extent_map *create_pinned_em(struct inode *inode, u64 start,

					   u64 len, u64 orig_start,

					   u64 block_start, u64 block_len,

					   u64 orig_block_len, u64 ram_bytes,

/* The callers of this must take lock_extent() */

static struct extent_map *create_io_em(struct inode *inode, u64 start, u64 len,

				       u64 orig_start, u64 block_start,

				       u64 block_len, u64 orig_block_len,

				       u64 ram_bytes, int compress_type,

				       int type)

{

	struct extent_map_tree *em_tree;
@@ -7556,6 +7503,11 @@ static struct extent_map *create_pinned_em(struct inode *inode, u64 start, 
	struct btrfs_root *root = BTRFS_I(inode)->root;

	int ret;



	ASSERT(type == BTRFS_ORDERED_PREALLOC ||

	       type == BTRFS_ORDERED_COMPRESSED ||

	       type == BTRFS_ORDERED_NOCOW ||

	       type == 0);



	em_tree = &BTRFS_I(inode)->extent_tree;

	em = alloc_extent_map();

	if (!em)
@@ -7563,8 +7515,6 @@ static struct extent_map *create_pinned_em(struct inode *inode, u64 start, 


	em->start = start;

	em->orig_start = orig_start;

	em->mod_start = start;

	em->mod_len = len;

	em->len = len;

	em->block_len = block_len;

	em->block_start = block_start;
@@ -7575,6 +7525,10 @@ static struct extent_map *create_pinned_em(struct inode *inode, u64 start, 
	set_bit(EXTENT_FLAG_PINNED, &em->flags);

	if (type == BTRFS_ORDERED_PREALLOC)

		set_bit(EXTENT_FLAG_FILLING, &em->flags);

	else if (type == BTRFS_ORDERED_COMPRESSED) {

		set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);

		em->compress_type = compress_type;

	}



	do {

		btrfs_drop_extent_cache(inode, em->start,
@@ -7582,6 +7536,10 @@ static struct extent_map *create_pinned_em(struct inode *inode, u64 start, 
		write_lock(&em_tree->lock);

		ret = add_extent_mapping(em_tree, em, 1);

		write_unlock(&em_tree->lock);

		/*

		 * The caller has taken lock_extent(), who could race with us

		 * to add em?

		 */

	} while (ret == -EEXIST);



	if (ret) {
@@ -7589,6 +7547,7 @@ static struct extent_map *create_pinned_em(struct inode *inode, u64 start, 
		return ERR_PTR(ret);

	}



	/* em got 2 refs now, callers needs to do free_extent_map once. */

	return em;

}