[PATCH 19/51] libxfs: implement XFS_IOC_SWAPEXT when rmap btree is enabled

Darrick J. Wong
2015-10-07T05:07:21Z

Synchronize the libxfs components of the kernel patch. No code
in xfsprogs actually calls this.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
libxfs/xfs_btree.c | 17 +++++++
libxfs/xfs_rmap.c | 112 +++++++++++++++++++++++++++++++++++++++++++++++
libxfs/xfs_rmap_btree.h | 8 +++
3 files changed, 137 insertions(+)

diff --git a/libxfs/xfs_btree.c b/libxfs/xfs_btree.c
index 8baaf28..000267a 100644
--- a/libxfs/xfs_btree.c
+++ b/libxfs/xfs_btree.c
@@ -29,6 +29,7 @@
#include "xfs_trace.h"
#include "xfs_cksum.h"
#include "xfs_alloc.h"
+#include "xfs_rmap_btree.h"

/*
* Cursor allocation zone.
@@ -3989,6 +3990,8 @@ xfs_btree_block_change_owner(
struct xfs_btree_block *block;
struct xfs_buf *bp;
union xfs_btree_ptr rptr;
+ struct xfs_owner_info old_oinfo, new_oinfo;
+ int error;

/* do right sibling readahead */
xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA);
@@ -4000,6 +4003,20 @@ xfs_btree_block_change_owner(
else
block->bb_u.s.bb_owner = cpu_to_be32(new_owner);

+ /* change rmap owners (bmbt blocks only) */
+ if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
+ XFS_RMAP_INO_BMBT_OWNER(&old_oinfo,
+ cur->bc_private.b.ip->i_ino,
+ cur->bc_private.b.whichfork);
+ XFS_RMAP_INO_BMBT_OWNER(&new_oinfo,
+ new_owner,
+ cur->bc_private.b.whichfork);
+ error = xfs_rmap_change_bmbt_owner(cur, bp, &old_oinfo,
+ &new_oinfo);
+ if (error)
+ return error;
+ }
+
/*
* If the block is a root block hosted in an inode, we might not have a
* buffer pointer here and we shouldn't attempt to log the change as the
diff --git a/libxfs/xfs_rmap.c b/libxfs/xfs_rmap.c
index 12aac59..adc561f 100644
--- a/libxfs/xfs_rmap.c
+++ b/libxfs/xfs_rmap.c
@@ -33,6 +33,8 @@
#include "xfs_rmap_btree.h"
#include "xfs_trans_space.h"
#include "xfs_trace.h"
+#include "xfs_bmap.h"
+#include "xfs_bmap_btree.h"

/*
* Lookup the first record less than or equal to [bno, len, owner, offset]
@@ -857,3 +859,113 @@ xfs_rmap_resize(
done:
return error;
}
+
+/**
+ * Change ownership of a file's BMBT block reverse-mappings.
+ */
+int
+xfs_rmap_change_bmbt_owner(
+ struct xfs_btree_cur *bcur,
+ struct xfs_buf *bp,
+ struct xfs_owner_info *old_owner,
+ struct xfs_owner_info *new_owner)
+{
+ struct xfs_buf *agfbp;
+ xfs_fsblock_t fsbno;
+ xfs_agnumber_t agno;
+ xfs_agblock_t agbno;
+ int error;
+
+ if (!xfs_sb_version_hasrmapbt(&bcur->bc_mp->m_sb) || !bp)
+ return 0;
+
+ fsbno = XFS_DADDR_TO_FSB(bcur->bc_mp, XFS_BUF_ADDR(bp));
+ agno = XFS_FSB_TO_AGNO(bcur->bc_mp, fsbno);
+ agbno = XFS_FSB_TO_AGBNO(bcur->bc_mp, fsbno);
+
+ error = xfs_read_agf(bcur->bc_mp, bcur->bc_tp, agno, 0, &agfbp);
+
+ error = xfs_rmap_free(bcur->bc_tp, agfbp, agno, agbno, 1, old_owner);
+ if (error)
+ goto err;
+
+ error = xfs_rmap_alloc(bcur->bc_tp, agfbp, agno, agbno, 1, new_owner);
+ if (error)
+ goto err;
+
+err:
+ xfs_trans_brelse(bcur->bc_tp, agfbp);
+ return error;
+}
+
+/**
+ * Change the ownership on a file's extent's reverse-mappings.
+ */
+int
+xfs_rmap_change_extent_owner(
+ struct xfs_mount *mp,
+ struct xfs_inode *ip,
+ xfs_ino_t ino,
+ xfs_fileoff_t isize,
+ struct xfs_trans *tp,
+ int whichfork,
+ xfs_ino_t new_owner)
+{
+ struct xfs_bmbt_irec imap;
+ struct xfs_btree_cur *cur = NULL;
+ struct xfs_buf *agfbp = NULL;
+ int nimaps;
+ xfs_fileoff_t offset;
+ xfs_filblks_t len;
+ xfs_agnumber_t agno;
+ int flags = 0;
+ int error;
+
+ if (!xfs_sb_version_hasrmapbt(&mp->m_sb))
+ return 0;
+
+ if (whichfork == XFS_ATTR_FORK)
+ flags |= XFS_BMAPI_ATTRFORK;
+
+ offset = 0;
+ len = XFS_B_TO_FSB(mp, isize);
+ nimaps = 1;
+ error = xfs_bmapi_read(ip, offset, len, &imap, &nimaps, flags);
+ while (error == 0 && nimaps > 0) {
+ if (imap.br_startblock == HOLESTARTBLOCK ||
+ imap.br_startblock == DELAYSTARTBLOCK)
+ goto advloop;
+
+ agno = XFS_FSB_TO_AGNO(mp, imap.br_startblock);
+
+ error = xfs_read_agf(mp, tp, agno, 0, &agfbp);
+ if (error)
+ break;
+
+ cur = xfs_rmapbt_init_cursor(mp, tp, agfbp, agno);
+
+ error = xfs_rmap_delete(cur, ino, whichfork, &imap);
+ if (error)
+ break;
+ error = xfs_rmap_insert(cur, new_owner, whichfork, &imap);
+ if (error)
+ break;
+
+ xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
+ cur = NULL;
+ xfs_trans_brelse(tp, agfbp);
+ agfbp = NULL;
+advloop:
+ offset += imap.br_blockcount;
+ len -= imap.br_blockcount;
+ nimaps = 1;
+ error = xfs_bmapi_read(ip, offset, len, &imap, &nimaps, flags);
+ }
+
+ if (cur)
+ xfs_btree_del_cursor(cur, error ? XFS_BTREE_ERROR :
+ XFS_BTREE_NOERROR);
+ if (agfbp)
+ xfs_trans_brelse(tp, agfbp);
+ return error;
+}
diff --git a/libxfs/xfs_rmap_btree.h b/libxfs/xfs_rmap_btree.h
index 0131d9a..5d248b5 100644
--- a/libxfs/xfs_rmap_btree.h
+++ b/libxfs/xfs_rmap_btree.h
@@ -88,4 +88,12 @@ int xfs_rmap_slide(struct xfs_btree_cur *rcur, xfs_ino_t ino, int whichfork,
int xfs_rmap_resize(struct xfs_btree_cur *rcur, xfs_ino_t ino, int whichfork,
struct xfs_bmbt_irec *PREV, long size_adj);

+/* functions for changing rmap ownership */
+int xfs_rmap_change_extent_owner(struct xfs_mount *mp, struct xfs_inode *ip,
+ xfs_ino_t ino, xfs_fileoff_t isize, struct xfs_trans *tp,
+ int whichfork, xfs_ino_t new_owner);
+int xfs_rmap_change_bmbt_owner(struct xfs_btree_cur *bcur, struct xfs_buf *bp,
+ struct xfs_owner_info *old_owner,
+ struct xfs_owner_info *new_owner);
+
#endif /* __XFS_RMAP_BTREE_H__ */