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Message-ID: <20140528194806.GA27499@birch.djwong.org> Date: Wed, 28 May 2014 12:48:06 -0700 From: "Darrick J. Wong" <darrick.wong@...cle.com> To: Lukáš Czerner <lczerner@...hat.com> Cc: tytso@....edu, linux-ext4@...r.kernel.org Subject: Re: [PATCH 2/2] libext2fs: support allocating uninit blocks in bmap2() On Tue, May 27, 2014 at 06:28:22PM +0200, Lukáš Czerner wrote: > On Wed, 7 May 2014, Darrick J. Wong wrote: > > > Date: Wed, 7 May 2014 17:14:47 -0700 > > From: Darrick J. Wong <darrick.wong@...cle.com> > > To: Lukáš Czerner <lczerner@...hat.com> > > Cc: tytso@....edu, linux-ext4@...r.kernel.org > > Subject: [PATCH 2/2] libext2fs: support allocating uninit blocks in bmap2() > > > > Here's the second part, which for the most part is the old patch, but wired up > > to use the bits in the other patch. > > Looks good > > Reviewed-by: Lukas Czerner <lczerner@...hat.com> > > but I wonder how effective will this be with zero range when we're > doing this on block at the time. Not a lot, but hopefully you used ext2fs_fallocate() (and extents) if you wanted more than one block. --D > > Thanks! > -Lukas > > > > > --D > > --- > > In order to support fallocate, we need to be able to have > > ext2fs_bmap2() allocate blocks and put them into uninitialized > > extents. There's a flag to do this in the extent code, but it's not > > exposed to the bmap2 interface, so plumb that in. Eventually fuse2fs > > or somebody will use it. > > > > Signed-off-by: Darrick J. Wong <darrick.wong@...cle.com> > > --- > > lib/ext2fs/bmap.c | 24 ++++++++++++++++++++++-- > > lib/ext2fs/ext2fs.h | 1 + > > 2 files changed, 23 insertions(+), 2 deletions(-) > > > > diff --git a/lib/ext2fs/bmap.c b/lib/ext2fs/bmap.c > > index c1d0e6f..a4dc8ef 100644 > > --- a/lib/ext2fs/bmap.c > > +++ b/lib/ext2fs/bmap.c > > @@ -72,6 +72,11 @@ static _BMAP_INLINE_ errcode_t block_ind_bmap(ext2_filsys fs, int flags, > > block_buf + fs->blocksize, &b); > > if (retval) > > return retval; > > + if (flags & BMAP_UNINIT) { > > + retval = ext2fs_zero_blocks2(fs, b, 1, NULL, NULL); > > + if (retval) > > + return retval; > > + } > > > > #ifdef WORDS_BIGENDIAN > > ((blk_t *) block_buf)[nr] = ext2fs_swab32(b); > > @@ -214,10 +219,13 @@ static errcode_t extent_bmap(ext2_filsys fs, ext2_ino_t ino, > > errcode_t retval = 0; > > blk64_t blk64 = 0; > > int alloc = 0; > > + int set_flags; > > + > > + set_flags = bmap_flags & BMAP_UNINIT ? EXT2_EXTENT_SET_BMAP_UNINIT : 0; > > > > if (bmap_flags & BMAP_SET) { > > retval = ext2fs_extent_set_bmap(handle, block, > > - *phys_blk, 0); > > + *phys_blk, set_flags); > > return retval; > > } > > retval = ext2fs_extent_goto(handle, block); > > @@ -254,7 +262,7 @@ got_block: > > alloc++; > > set_extent: > > retval = ext2fs_extent_set_bmap(handle, block, > > - blk64, 0); > > + blk64, set_flags); > > if (retval) { > > ext2fs_block_alloc_stats2(fs, blk64, -1); > > return retval; > > @@ -345,6 +353,12 @@ errcode_t ext2fs_bmap2(ext2_filsys fs, ext2_ino_t ino, struct ext2_inode *inode, > > goto done; > > } > > > > + if ((bmap_flags & BMAP_SET) && (bmap_flags & BMAP_UNINIT)) { > > + retval = ext2fs_zero_blocks2(fs, *phys_blk, 1, NULL, NULL); > > + if (retval) > > + goto done; > > + } > > + > > if (block < EXT2_NDIR_BLOCKS) { > > if (bmap_flags & BMAP_SET) { > > b = *phys_blk; > > @@ -360,6 +374,12 @@ errcode_t ext2fs_bmap2(ext2_filsys fs, ext2_ino_t ino, struct ext2_inode *inode, > > retval = ext2fs_alloc_block(fs, b, block_buf, &b); > > if (retval) > > goto done; > > + if (bmap_flags & BMAP_UNINIT) { > > + retval = ext2fs_zero_blocks2(fs, b, 1, NULL, > > + NULL); > > + if (retval) > > + goto done; > > + } > > inode_bmap(inode, block) = b; > > blocks_alloc++; > > *phys_blk = b; > > diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h > > index 599c972..819a14a 100644 > > --- a/lib/ext2fs/ext2fs.h > > +++ b/lib/ext2fs/ext2fs.h > > @@ -527,6 +527,7 @@ typedef struct ext2_icount *ext2_icount_t; > > */ > > #define BMAP_ALLOC 0x0001 > > #define BMAP_SET 0x0002 > > +#define BMAP_UNINIT 0x0004 > > > > /* > > * Returned flags from ext2fs_bmap > > -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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