From 9f3afb57d5f1e7145986132106c6ca91f8136cc2 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Mon, 3 Oct 2016 09:11:28 -0700 Subject: xfs: implement deferred bmbt map/unmap operations Implement deferred versions of the inode block map/unmap functions. These will be used in subsequent patches to make reflink operations atomic. Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig --- fs/xfs/libxfs/xfs_bmap.c | 143 ++++++++++++++++++++++++++++++++++++++++++++++ fs/xfs/libxfs/xfs_bmap.h | 9 +++ fs/xfs/libxfs/xfs_defer.h | 1 + 3 files changed, 153 insertions(+) (limited to 'fs/xfs/libxfs') diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c index ee9f54bdf084..5828814c119c 100644 --- a/fs/xfs/libxfs/xfs_bmap.c +++ b/fs/xfs/libxfs/xfs_bmap.c @@ -6062,3 +6062,146 @@ out: xfs_trans_cancel(tp); return error; } + +/* Deferred mapping is only for real extents in the data fork. */ +static bool +xfs_bmap_is_update_needed( + struct xfs_bmbt_irec *bmap) +{ + return bmap->br_startblock != HOLESTARTBLOCK && + bmap->br_startblock != DELAYSTARTBLOCK; +} + +/* Record a bmap intent. */ +static int +__xfs_bmap_add( + struct xfs_mount *mp, + struct xfs_defer_ops *dfops, + enum xfs_bmap_intent_type type, + struct xfs_inode *ip, + int whichfork, + struct xfs_bmbt_irec *bmap) +{ + int error; + struct xfs_bmap_intent *bi; + + trace_xfs_bmap_defer(mp, + XFS_FSB_TO_AGNO(mp, bmap->br_startblock), + type, + XFS_FSB_TO_AGBNO(mp, bmap->br_startblock), + ip->i_ino, whichfork, + bmap->br_startoff, + bmap->br_blockcount, + bmap->br_state); + + bi = kmem_alloc(sizeof(struct xfs_bmap_intent), KM_SLEEP | KM_NOFS); + INIT_LIST_HEAD(&bi->bi_list); + bi->bi_type = type; + bi->bi_owner = ip; + bi->bi_whichfork = whichfork; + bi->bi_bmap = *bmap; + + error = xfs_defer_join(dfops, bi->bi_owner); + if (error) { + kmem_free(bi); + return error; + } + + xfs_defer_add(dfops, XFS_DEFER_OPS_TYPE_BMAP, &bi->bi_list); + return 0; +} + +/* Map an extent into a file. */ +int +xfs_bmap_map_extent( + struct xfs_mount *mp, + struct xfs_defer_ops *dfops, + struct xfs_inode *ip, + struct xfs_bmbt_irec *PREV) +{ + if (!xfs_bmap_is_update_needed(PREV)) + return 0; + + return __xfs_bmap_add(mp, dfops, XFS_BMAP_MAP, ip, + XFS_DATA_FORK, PREV); +} + +/* Unmap an extent out of a file. */ +int +xfs_bmap_unmap_extent( + struct xfs_mount *mp, + struct xfs_defer_ops *dfops, + struct xfs_inode *ip, + struct xfs_bmbt_irec *PREV) +{ + if (!xfs_bmap_is_update_needed(PREV)) + return 0; + + return __xfs_bmap_add(mp, dfops, XFS_BMAP_UNMAP, ip, + XFS_DATA_FORK, PREV); +} + +/* + * Process one of the deferred bmap operations. We pass back the + * btree cursor to maintain our lock on the bmapbt between calls. + */ +int +xfs_bmap_finish_one( + struct xfs_trans *tp, + struct xfs_defer_ops *dfops, + struct xfs_inode *ip, + enum xfs_bmap_intent_type type, + int whichfork, + xfs_fileoff_t startoff, + xfs_fsblock_t startblock, + xfs_filblks_t blockcount, + xfs_exntst_t state) +{ + struct xfs_bmbt_irec bmap; + int nimaps = 1; + xfs_fsblock_t firstfsb; + int flags = XFS_BMAPI_REMAP; + int done; + int error = 0; + + bmap.br_startblock = startblock; + bmap.br_startoff = startoff; + bmap.br_blockcount = blockcount; + bmap.br_state = state; + + trace_xfs_bmap_deferred(tp->t_mountp, + XFS_FSB_TO_AGNO(tp->t_mountp, startblock), type, + XFS_FSB_TO_AGBNO(tp->t_mountp, startblock), + ip->i_ino, whichfork, startoff, blockcount, state); + + if (whichfork != XFS_DATA_FORK && whichfork != XFS_ATTR_FORK) + return -EFSCORRUPTED; + if (whichfork == XFS_ATTR_FORK) + flags |= XFS_BMAPI_ATTRFORK; + + if (XFS_TEST_ERROR(false, tp->t_mountp, + XFS_ERRTAG_BMAP_FINISH_ONE, + XFS_RANDOM_BMAP_FINISH_ONE)) + return -EIO; + + switch (type) { + case XFS_BMAP_MAP: + firstfsb = bmap.br_startblock; + error = xfs_bmapi_write(tp, ip, bmap.br_startoff, + bmap.br_blockcount, flags, &firstfsb, + bmap.br_blockcount, &bmap, &nimaps, + dfops); + break; + case XFS_BMAP_UNMAP: + error = xfs_bunmapi(tp, ip, bmap.br_startoff, + bmap.br_blockcount, flags, 1, &firstfsb, + dfops, &done); + ASSERT(done); + break; + default: + ASSERT(0); + error = -EFSCORRUPTED; + } + + return error; +} diff --git a/fs/xfs/libxfs/xfs_bmap.h b/fs/xfs/libxfs/xfs_bmap.h index 9c0406720d69..b40ef797a4bf 100644 --- a/fs/xfs/libxfs/xfs_bmap.h +++ b/fs/xfs/libxfs/xfs_bmap.h @@ -231,4 +231,13 @@ struct xfs_bmap_intent { struct xfs_bmbt_irec bi_bmap; }; +int xfs_bmap_finish_one(struct xfs_trans *tp, struct xfs_defer_ops *dfops, + struct xfs_inode *ip, enum xfs_bmap_intent_type type, + int whichfork, xfs_fileoff_t startoff, xfs_fsblock_t startblock, + xfs_filblks_t blockcount, xfs_exntst_t state); +int xfs_bmap_map_extent(struct xfs_mount *mp, struct xfs_defer_ops *dfops, + struct xfs_inode *ip, struct xfs_bmbt_irec *imap); +int xfs_bmap_unmap_extent(struct xfs_mount *mp, struct xfs_defer_ops *dfops, + struct xfs_inode *ip, struct xfs_bmbt_irec *imap); + #endif /* __XFS_BMAP_H__ */ diff --git a/fs/xfs/libxfs/xfs_defer.h b/fs/xfs/libxfs/xfs_defer.h index 4d94a869e581..f6e93ef0bffe 100644 --- a/fs/xfs/libxfs/xfs_defer.h +++ b/fs/xfs/libxfs/xfs_defer.h @@ -51,6 +51,7 @@ struct xfs_defer_pending { * find all the space it needs. */ enum xfs_defer_ops_type { + XFS_DEFER_OPS_TYPE_BMAP, XFS_DEFER_OPS_TYPE_REFCOUNT, XFS_DEFER_OPS_TYPE_RMAP, XFS_DEFER_OPS_TYPE_FREE, -- cgit v1.2.3