Commit fffb6412 authored by Andreas Gruenbacher's avatar Andreas Gruenbacher Committed by Bob Peterson
Browse files

gfs2: Zero out fallocated blocks in fallocate_chunk 



Instead of zeroing out fallocated blocks in gfs2_iomap_alloc, zero them
out in fallocate_chunk, much higher up the call stack.  This gets rid of
gfs2's abuse of the IOMAP_ZERO flag as well as the gfs2 specific zeronew
buffer flag.  I can't think of a reason why zeroing out the blocks in
gfs2_iomap_alloc would have any benefits: there is no additional locking
at that level that would add protection to the newly allocated blocks.

While at it, change fallocate over from gs2_block_map to gfs2_iomap_begin.

Signed-off-by: default avatarAndreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: default avatarBob Peterson <rpeterso@redhat.com>
Acked-by: default avatarChristoph Hellwig <hch@lst.de>
parent bb491ce6

fs/gfs2/bmap.c

+0 −13
Original line number Diff line number Diff line
@@ -491,14 +491,12 @@ static int gfs2_iomap_alloc(struct inode *inode, struct iomap *iomap, 
{

	struct gfs2_inode *ip = GFS2_I(inode);

	struct gfs2_sbd *sdp = GFS2_SB(inode);

	struct super_block *sb = sdp->sd_vfs;

	struct buffer_head *dibh = mp->mp_bh[0];

	u64 bn;

	unsigned n, i, blks, alloced = 0, iblks = 0, branch_start = 0;

	unsigned dblks = 0;

	unsigned ptrs_per_blk;

	const unsigned end_of_metadata = mp->mp_fheight - 1;

	int ret;

	enum alloc_state state;

	__be64 *ptr;

	__be64 zero_bn = 0;
@@ -607,15 +605,6 @@ static int gfs2_iomap_alloc(struct inode *inode, struct iomap *iomap, 
			iomap->flags |= IOMAP_F_NEW;

			while (n-- > 0)

				*ptr++ = cpu_to_be64(bn++);

			if (flags & IOMAP_ZERO) {

				ret = sb_issue_zeroout(sb, iomap->addr >> inode->i_blkbits,

						       dblks, GFP_NOFS);

				if (ret) {

					fs_err(sdp,

					       "Failed to zero data buffers\n");

					flags &= ~IOMAP_ZERO;

				}

			}

			break;

		}

	} while (iomap->addr == IOMAP_NULL_ADDR);
@@ -846,8 +835,6 @@ int gfs2_block_map(struct inode *inode, sector_t lblock, 


	if (create)

		flags |= IOMAP_WRITE;

	if (buffer_zeronew(bh_map))

		flags |= IOMAP_ZERO;

	ret = gfs2_iomap_begin(inode, (loff_t)lblock << inode->i_blkbits,

			       bh_map->b_size, flags, &iomap);

	if (ret) {

fs/gfs2/file.c

+14 −15
Original line number Diff line number Diff line
@@ -729,11 +729,12 @@ static ssize_t gfs2_file_write_iter(struct kiocb *iocb, struct iov_iter *from) 
static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len,

			   int mode)

{

	struct super_block *sb = inode->i_sb;

	struct gfs2_inode *ip = GFS2_I(inode);

	loff_t end = offset + len;

	struct buffer_head *dibh;

	struct iomap iomap;

	int error;

	unsigned int nr_blks;

	sector_t lblock = offset >> inode->i_blkbits;



	error = gfs2_meta_inode_buffer(ip, &dibh);

	if (unlikely(error))
@@ -747,21 +748,19 @@ static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len, 
			goto out;

	}



	while (len) {

		struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };

		bh_map.b_size = len;

		set_buffer_zeronew(&bh_map);



		error = gfs2_block_map(inode, lblock, &bh_map, 1);

		if (unlikely(error))

	while (offset < end) {

		error = gfs2_iomap_begin(inode, offset, end - offset,

					 IOMAP_WRITE, &iomap);

		if (error)

			goto out;

		len -= bh_map.b_size;

		nr_blks = bh_map.b_size >> inode->i_blkbits;

		lblock += nr_blks;

		if (!buffer_new(&bh_map))

		offset = iomap.offset + iomap.length;

		if (iomap.type != IOMAP_HOLE)

			continue;

		if (unlikely(!buffer_zeronew(&bh_map))) {

			error = -EIO;

		error = sb_issue_zeroout(sb, iomap.addr >> inode->i_blkbits,

					 iomap.length >> inode->i_blkbits,

					 GFP_NOFS);

		if (error) {

			fs_err(GFS2_SB(inode), "Failed to zero data buffers\n");

			goto out;

		}

	}

fs/gfs2/incore.h

+0 −3
Original line number Diff line number Diff line
@@ -130,15 +130,12 @@ static inline bool gfs2_rbm_eq(const struct gfs2_rbm *rbm1, 
enum gfs2_state_bits {

	BH_Pinned = BH_PrivateStart,

	BH_Escaped = BH_PrivateStart + 1,

	BH_Zeronew = BH_PrivateStart + 2,

};



BUFFER_FNS(Pinned, pinned)

TAS_BUFFER_FNS(Pinned, pinned)

BUFFER_FNS(Escaped, escaped)

TAS_BUFFER_FNS(Escaped, escaped)

BUFFER_FNS(Zeronew, zeronew)

TAS_BUFFER_FNS(Zeronew, zeronew)



struct gfs2_bufdata {

	struct buffer_head *bd_bh;

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