Commit 7dbdb443 authored by Nikolay Borisov's avatar Nikolay Borisov Committed by David Sterba
Browse files

btrfs: remove crc_check logic from free space 



Following removal of the ino cache io_ctl_init will be called only on
behalf of the freespace inode. In this case we always want to check
CRCs so conditional code that depended on io_ctl::check_crc can be
removed.

Signed-off-by: default avatarNikolay Borisov <nborisov@suse.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 5297199a

fs/btrfs/free-space-cache.c

+5 −32
Original line number Diff line number Diff line
@@ -305,16 +305,11 @@ static int io_ctl_init(struct btrfs_io_ctl *io_ctl, struct inode *inode, 
		       int write)

{

	int num_pages;

	int check_crcs = 0;



	num_pages = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE);



	if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FREE_INO_OBJECTID)

		check_crcs = 1;



	/* Make sure we can fit our crcs and generation into the first page */

	if (write && check_crcs &&

	    (num_pages * sizeof(u32) + sizeof(u64)) > PAGE_SIZE)

	if (write && (num_pages * sizeof(u32) + sizeof(u64)) > PAGE_SIZE)

		return -ENOSPC;



	memset(io_ctl, 0, sizeof(struct btrfs_io_ctl));
@@ -325,7 +320,6 @@ static int io_ctl_init(struct btrfs_io_ctl *io_ctl, struct inode *inode, 


	io_ctl->num_pages = num_pages;

	io_ctl->fs_info = btrfs_sb(inode->i_sb);

	io_ctl->check_crcs = check_crcs;

	io_ctl->inode = inode;



	return 0;
@@ -420,13 +414,8 @@ static void io_ctl_set_generation(struct btrfs_io_ctl *io_ctl, u64 generation) 
	 * Skip the csum areas.  If we don't check crcs then we just have a

	 * 64bit chunk at the front of the first page.

	 */

	if (io_ctl->check_crcs) {

	io_ctl->cur += (sizeof(u32) * io_ctl->num_pages);

	io_ctl->size -= sizeof(u64) + (sizeof(u32) * io_ctl->num_pages);

	} else {

		io_ctl->cur += sizeof(u64);

		io_ctl->size -= sizeof(u64) * 2;

	}



	put_unaligned_le64(generation, io_ctl->cur);

	io_ctl->cur += sizeof(u64);
@@ -440,14 +429,8 @@ static int io_ctl_check_generation(struct btrfs_io_ctl *io_ctl, u64 generation) 
	 * Skip the crc area.  If we don't check crcs then we just have a 64bit

	 * chunk at the front of the first page.

	 */

	if (io_ctl->check_crcs) {

	io_ctl->cur += sizeof(u32) * io_ctl->num_pages;

		io_ctl->size -= sizeof(u64) +

			(sizeof(u32) * io_ctl->num_pages);

	} else {

		io_ctl->cur += sizeof(u64);

		io_ctl->size -= sizeof(u64) * 2;

	}

	io_ctl->size -= sizeof(u64) + (sizeof(u32) * io_ctl->num_pages);



	cache_gen = get_unaligned_le64(io_ctl->cur);

	if (cache_gen != generation) {
@@ -467,11 +450,6 @@ static void io_ctl_set_crc(struct btrfs_io_ctl *io_ctl, int index) 
	u32 crc = ~(u32)0;

	unsigned offset = 0;



	if (!io_ctl->check_crcs) {

		io_ctl_unmap_page(io_ctl);

		return;

	}



	if (index == 0)

		offset = sizeof(u32) * io_ctl->num_pages;
@@ -489,11 +467,6 @@ static int io_ctl_check_crc(struct btrfs_io_ctl *io_ctl, int index) 
	u32 crc = ~(u32)0;

	unsigned offset = 0;



	if (!io_ctl->check_crcs) {

		io_ctl_map_page(io_ctl, 0);

		return 0;

	}



	if (index == 0)

		offset = sizeof(u32) * io_ctl->num_pages;

fs/btrfs/free-space-cache.h

+0 −1
Original line number Diff line number Diff line
@@ -76,7 +76,6 @@ struct btrfs_io_ctl { 
	int num_pages;

	int entries;

	int bitmaps;

	unsigned check_crcs:1;

};



struct inode *lookup_free_space_inode(struct btrfs_block_group *block_group,