From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay3.corp.sgi.com [198.149.34.15]) by oss.sgi.com (Postfix) with ESMTP id 002617DDA for ; Thu, 25 Aug 2016 18:37:18 -0500 (CDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by relay3.corp.sgi.com (Postfix) with ESMTP id 775A4AC002 for ; Thu, 25 Aug 2016 16:37:17 -0700 (PDT) Received: from userp1040.oracle.com (userp1040.oracle.com [156.151.31.81]) by cuda.sgi.com with ESMTP id qHHcP7sH51thQpo7 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO) for ; Thu, 25 Aug 2016 16:37:15 -0700 (PDT) Subject: [PATCH 48/71] xfs: teach get_bmapx about shared extents and the CoW fork From: "Darrick J. Wong" Date: Thu, 25 Aug 2016 16:37:11 -0700 Message-ID: <147216823143.867.5001532335455709937.stgit@birch.djwong.org> In-Reply-To: <147216791538.867.12413509832420924168.stgit@birch.djwong.org> References: <147216791538.867.12413509832420924168.stgit@birch.djwong.org> MIME-Version: 1.0 List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: david@fromorbit.com, darrick.wong@oracle.com Cc: linux-xfs@vger.kernel.org, xfs@oss.sgi.com Teach xfs_getbmapx how to report shared extents and CoW fork contents accurately in the bmap output by querying the refcount btree appropriately. Signed-off-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_fs.h | 4 + fs/xfs/xfs_bmap_util.c | 132 +++++++++++++++++++++++++++++++++++++++++++----- 2 files changed, 121 insertions(+), 15 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 4ece4f2..5e1c679f 100644 --- a/fs/xfs/xfs_bmap_util.c +++ b/fs/xfs/xfs_bmap_util.c @@ -42,6 +42,9 @@ #include "xfs_icache.h" #include "xfs_log.h" #include "xfs_rmap_btree.h" +#include "xfs_iomap.h" +#include "xfs_reflink.h" +#include "xfs_refcount.h" /* Kernel only BMAP related definitions and functions */ @@ -389,11 +392,13 @@ 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 */ __int64_t end, /* last block requested */ - xfs_fsblock_t startblock) + xfs_fsblock_t startblock, + bool moretocome) { __int64_t fixlen; xfs_mount_t *mp; /* file system mount point */ @@ -418,8 +423,9 @@ 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); - if (xfs_iext_bno_to_ext(ifp, fileblock, &lastx) && + ifp = XFS_IFORK_PTR(ip, whichfork); + if (!moretocome && + 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; } @@ -459,12 +465,23 @@ xfs_getbmap( int iflags; /* interface flags */ int bmapi_flags; /* flags for xfs_bmapi */ int cur_ext = 0; + struct xfs_bmbt_irec inject_map; 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 && @@ -480,7 +497,15 @@ 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) @@ -494,6 +519,7 @@ xfs_getbmap( prealloced = 0; fixlen = XFS_ISIZE(ip); } + break; } if (bmv->bmv_length == -1) { @@ -520,7 +546,8 @@ 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); @@ -538,8 +565,14 @@ 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; } /* @@ -581,7 +614,8 @@ xfs_getbmap( goto out_free_map; ASSERT(nmap <= subnex); - for (i = 0; i < nmap && nexleft && bmv->bmv_length; i++) { + for (i = 0; i < nmap && nexleft && bmv->bmv_length && + cur_ext < bmv->bmv_count; i++) { out[cur_ext].bmv_oflags = 0; if (map[i].br_state == XFS_EXT_UNWRITTEN) out[cur_ext].bmv_oflags |= BMV_OF_PREALLOC; @@ -614,9 +648,74 @@ xfs_getbmap( goto out_free_map; } - if (!xfs_getbmapx_fix_eof_hole(ip, &out[cur_ext], - prealloced, bmvend, - map[i].br_startblock)) + /* Is this a shared block? */ + inject_map.br_blockcount = 0; + 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 agbno; + xfs_agblock_t ebno; + xfs_extlen_t elen; + xfs_extlen_t nlen; + + agbno = XFS_FSB_TO_AGBNO(mp, + map[i].br_startblock); + error = xfs_reflink_find_shared(mp, + XFS_FSB_TO_AGNO(mp, + map[i].br_startblock), + agbno, + map[i].br_blockcount, + &ebno, &elen, true); + if (error) + goto out_free_map; + + inject_map = map[i]; + if (agbno == ebno) { + /* + * Shared extent at (agbno, elen). + * Shrink the reported extent length + * and prepare to move the start of + * map[i] to agbno+elen, with the aim + * of (re)formatting the new map[i] + * the next time through the inner + * loop. + */ + out[cur_ext].bmv_length = + XFS_FSB_TO_BB(mp, elen); + out[cur_ext].bmv_oflags |= + BMV_OF_SHARED; + inject_map.br_startblock += elen; + inject_map.br_startoff += elen; + inject_map.br_blockcount -= elen; + map[i].br_blockcount -= elen; + } else { + /* + * There's an unshared extent + * (agbno, ebno - agbno) followed by + * shared extent at (ebno, elen). + * Shrink the reported extent length to + * cover only the unshared extent and + * prepare to move up the start of + * map[i] to ebno, with the aim of + * (re)formatting the new map[i] the + * next time through the inner + * loop. + */ + nlen = ebno - agbno; + out[cur_ext].bmv_length = + XFS_FSB_TO_BB(mp, nlen); + inject_map.br_startblock += nlen; + inject_map.br_startoff += nlen; + inject_map.br_blockcount -= nlen; + map[i].br_blockcount -= nlen; + } + } + + if (!xfs_getbmapx_fix_eof_hole(ip, whichfork, + &out[cur_ext], prealloced, bmvend, + map[i].br_startblock, + inject_map.br_blockcount != 0)) goto out_free_map; bmv->bmv_offset = @@ -636,11 +735,16 @@ xfs_getbmap( continue; } - nexleft--; + if (inject_map.br_blockcount) { + map[i] = inject_map; + i--; + } else + nexleft--; bmv->bmv_entries++; cur_ext++; } - } while (nmap && nexleft && bmv->bmv_length); + } while (nmap && nexleft && bmv->bmv_length && + cur_ext < bmv->bmv_count); out_free_map: kmem_free(map); _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs