From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp1040.oracle.com ([156.151.31.81]:30291 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755130AbcFQB1z (ORCPT ); Thu, 16 Jun 2016 21:27:55 -0400 Subject: [PATCH 092/119] xfs: teach get_bmapx and fiemap about shared extents and the CoW fork From: "Darrick J. Wong" To: david@fromorbit.com, darrick.wong@oracle.com Cc: linux-fsdevel@vger.kernel.org, vishal.l.verma@intel.com, xfs@oss.sgi.com Date: Thu, 16 Jun 2016 18:27:45 -0700 Message-ID: <146612686537.12839.9576429345676177064.stgit@birch.djwong.org> In-Reply-To: <146612627129.12839.3827886950949809165.stgit@birch.djwong.org> References: <146612627129.12839.3827886950949809165.stgit@birch.djwong.org> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Teach xfs_getbmapx how to report shared extents and CoW fork contents, then modify the FIEMAP formatters to set the appropriate flags. A previous version of this patch only modified the fiemap formatter, which is insufficient. Signed-off-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_fs.h | 4 ++- fs/xfs/xfs_bmap_util.c | 66 ++++++++++++++++++++++++++++++++++++++++++------ fs/xfs/xfs_iops.c | 2 + 3 files changed, 63 insertions(+), 9 deletions(-) diff --git a/fs/xfs/libxfs/xfs_fs.h b/fs/xfs/libxfs/xfs_fs.h index 6230230..b1af423 100644 --- a/fs/xfs/libxfs/xfs_fs.h +++ b/fs/xfs/libxfs/xfs_fs.h @@ -81,14 +81,16 @@ struct getbmapx { #define BMV_IF_PREALLOC 0x4 /* rtn status BMV_OF_PREALLOC if req */ #define BMV_IF_DELALLOC 0x8 /* rtn status BMV_OF_DELALLOC if req */ #define BMV_IF_NO_HOLES 0x10 /* Do not return holes */ +#define BMV_IF_COWFORK 0x20 /* return CoW fork rather than data */ #define BMV_IF_VALID \ (BMV_IF_ATTRFORK|BMV_IF_NO_DMAPI_READ|BMV_IF_PREALLOC| \ - BMV_IF_DELALLOC|BMV_IF_NO_HOLES) + BMV_IF_DELALLOC|BMV_IF_NO_HOLES|BMV_IF_COWFORK) /* bmv_oflags values - returned for each non-header segment */ #define BMV_OF_PREALLOC 0x1 /* segment = unwritten pre-allocation */ #define BMV_OF_DELALLOC 0x2 /* segment = delayed allocation */ #define BMV_OF_LAST 0x4 /* segment is the last in the file */ +#define BMV_OF_SHARED 0x8 /* segment shared with another file */ /* * Structure for XFS_IOC_FSSETDM. diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c index 9285111..3d71a17 100644 --- a/fs/xfs/xfs_bmap_util.c +++ b/fs/xfs/xfs_bmap_util.c @@ -44,6 +44,7 @@ #include "xfs_rmap_btree.h" #include "xfs_iomap.h" #include "xfs_reflink.h" +#include "xfs_refcount.h" /* Kernel only BMAP related definitions and functions */ @@ -391,6 +392,7 @@ xfs_bmap_count_blocks( STATIC int xfs_getbmapx_fix_eof_hole( xfs_inode_t *ip, /* xfs incore inode pointer */ + int whichfork, struct getbmapx *out, /* output structure */ int prealloced, /* this is a file with * preallocated data space */ @@ -420,7 +422,7 @@ xfs_getbmapx_fix_eof_hole( else out->bmv_block = xfs_fsb_to_db(ip, startblock); fileblock = XFS_BB_TO_FSB(ip->i_mount, out->bmv_offset); - ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK); + ifp = XFS_IFORK_PTR(ip, whichfork); if (xfs_iext_bno_to_ext(ifp, fileblock, &lastx) && (lastx == (ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t))-1)) out->bmv_oflags |= BMV_OF_LAST; @@ -464,9 +466,19 @@ xfs_getbmap( mp = ip->i_mount; iflags = bmv->bmv_iflags; - whichfork = iflags & BMV_IF_ATTRFORK ? XFS_ATTR_FORK : XFS_DATA_FORK; - if (whichfork == XFS_ATTR_FORK) { + if ((iflags & BMV_IF_ATTRFORK) && (iflags & BMV_IF_COWFORK)) + return -EINVAL; + + if (iflags & BMV_IF_ATTRFORK) + whichfork = XFS_ATTR_FORK; + else if (iflags & BMV_IF_COWFORK) + whichfork = XFS_COW_FORK; + else + whichfork = XFS_DATA_FORK; + + switch (whichfork) { + case XFS_ATTR_FORK: if (XFS_IFORK_Q(ip)) { if (ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS && ip->i_d.di_aformat != XFS_DINODE_FMT_BTREE && @@ -482,7 +494,15 @@ xfs_getbmap( prealloced = 0; fixlen = 1LL << 32; - } else { + break; + case XFS_COW_FORK: + if (ip->i_cformat != XFS_DINODE_FMT_EXTENTS) + return -EINVAL; + + prealloced = 0; + fixlen = XFS_ISIZE(ip); + break; + default: if (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS && ip->i_d.di_format != XFS_DINODE_FMT_BTREE && ip->i_d.di_format != XFS_DINODE_FMT_LOCAL) @@ -496,6 +516,7 @@ xfs_getbmap( prealloced = 0; fixlen = XFS_ISIZE(ip); } + break; } if (bmv->bmv_length == -1) { @@ -522,7 +543,8 @@ xfs_getbmap( return -ENOMEM; xfs_ilock(ip, XFS_IOLOCK_SHARED); - if (whichfork == XFS_DATA_FORK) { + switch (whichfork) { + case XFS_DATA_FORK: if (!(iflags & BMV_IF_DELALLOC) && (ip->i_delayed_blks || XFS_ISIZE(ip) > ip->i_d.di_size)) { error = filemap_write_and_wait(VFS_I(ip)->i_mapping); @@ -540,8 +562,14 @@ xfs_getbmap( } lock = xfs_ilock_data_map_shared(ip); - } else { + break; + case XFS_COW_FORK: + lock = XFS_ILOCK_SHARED; + xfs_ilock(ip, lock); + break; + case XFS_ATTR_FORK: lock = xfs_ilock_attr_map_shared(ip); + break; } /* @@ -616,8 +644,30 @@ xfs_getbmap( goto out_free_map; } - if (!xfs_getbmapx_fix_eof_hole(ip, &out[cur_ext], - prealloced, bmvend, + /* Is this a shared block? */ + if (whichfork == XFS_DATA_FORK && + map[i].br_startblock != DELAYSTARTBLOCK && + map[i].br_startblock != HOLESTARTBLOCK && + !ISUNWRITTEN(&map[i]) && xfs_is_reflink_inode(ip)) { + xfs_agblock_t ebno; + xfs_extlen_t elen; + + error = xfs_refcount_find_shared(mp, + XFS_FSB_TO_AGNO(mp, + map[i].br_startblock), + XFS_FSB_TO_AGBNO(mp, + map[i].br_startblock), + map[i].br_blockcount, + &ebno, &elen, true); + if (error) + goto out_free_map; + if (elen) + out[cur_ext].bmv_oflags |= + BMV_OF_SHARED; + } + + if (!xfs_getbmapx_fix_eof_hole(ip, whichfork, + &out[cur_ext], prealloced, bmvend, map[i].br_startblock)) goto out_free_map; diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c index c5d4eba..e57bfe8 100644 --- a/fs/xfs/xfs_iops.c +++ b/fs/xfs/xfs_iops.c @@ -1025,6 +1025,8 @@ xfs_fiemap_format( if (bmv->bmv_oflags & BMV_OF_PREALLOC) fiemap_flags |= FIEMAP_EXTENT_UNWRITTEN; + else if (bmv->bmv_oflags & BMV_OF_SHARED) + fiemap_flags |= FIEMAP_EXTENT_SHARED; else if (bmv->bmv_oflags & BMV_OF_DELALLOC) { fiemap_flags |= (FIEMAP_EXTENT_DELALLOC | FIEMAP_EXTENT_UNKNOWN);