[XFS] implement generic xfs_btree_increment
From: Dave Chinner <dgc@sgi.com> Because this is the first major generic btree routine this patch includes some infrastrucure, first a few routines to deal with a btree block that can be either in short or long form, second xfs_btree_read_buf_block, which is the new central routine to read a btree block given a cursor, and third the new xfs_btree_ptr_addr routine to calculate the address for a given btree pointer record. [hch: split out from bigger patch and minor adaptions] SGI-PV: 985583 SGI-Modid: xfs-linux-melb:xfs-kern:32190a Signed-off-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: Bill O'Donnell <billodo@sgi.com> Signed-off-by: David Chinner <david@fromorbit.com>
This commit is contained in:
Christoph Hellwig
committed by
Lachlan McIlroy
Lachlan McIlroy
parent
65f1eaeac0
commit
637aa50f46
@@ -35,6 +35,7 @@
|
||||
#include "xfs_dinode.h"
|
||||
#include "xfs_inode.h"
|
||||
#include "xfs_btree.h"
|
||||
#include "xfs_btree_trace.h"
|
||||
#include "xfs_ialloc.h"
|
||||
#include "xfs_error.h"
|
||||
|
||||
@@ -949,3 +950,224 @@ xfs_btree_setbuf(
|
||||
cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
|
||||
}
|
||||
}
|
||||
|
||||
STATIC int
|
||||
xfs_btree_ptr_is_null(
|
||||
struct xfs_btree_cur *cur,
|
||||
union xfs_btree_ptr *ptr)
|
||||
{
|
||||
if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
|
||||
return be64_to_cpu(ptr->l) == NULLFSBLOCK;
|
||||
else
|
||||
return be32_to_cpu(ptr->s) == NULLAGBLOCK;
|
||||
}
|
||||
|
||||
/*
|
||||
* Get/set/init sibling pointers
|
||||
*/
|
||||
STATIC void
|
||||
xfs_btree_get_sibling(
|
||||
struct xfs_btree_cur *cur,
|
||||
struct xfs_btree_block *block,
|
||||
union xfs_btree_ptr *ptr,
|
||||
int lr)
|
||||
{
|
||||
ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB);
|
||||
|
||||
if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
|
||||
if (lr == XFS_BB_RIGHTSIB)
|
||||
ptr->l = block->bb_u.l.bb_rightsib;
|
||||
else
|
||||
ptr->l = block->bb_u.l.bb_leftsib;
|
||||
} else {
|
||||
if (lr == XFS_BB_RIGHTSIB)
|
||||
ptr->s = block->bb_u.s.bb_rightsib;
|
||||
else
|
||||
ptr->s = block->bb_u.s.bb_leftsib;
|
||||
}
|
||||
}
|
||||
|
||||
STATIC xfs_daddr_t
|
||||
xfs_btree_ptr_to_daddr(
|
||||
struct xfs_btree_cur *cur,
|
||||
union xfs_btree_ptr *ptr)
|
||||
{
|
||||
if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
|
||||
ASSERT(be64_to_cpu(ptr->l) != NULLFSBLOCK);
|
||||
|
||||
return XFS_FSB_TO_DADDR(cur->bc_mp, be64_to_cpu(ptr->l));
|
||||
} else {
|
||||
ASSERT(cur->bc_private.a.agno != NULLAGNUMBER);
|
||||
ASSERT(be32_to_cpu(ptr->s) != NULLAGBLOCK);
|
||||
|
||||
return XFS_AGB_TO_DADDR(cur->bc_mp, cur->bc_private.a.agno,
|
||||
be32_to_cpu(ptr->s));
|
||||
}
|
||||
}
|
||||
|
||||
STATIC void
|
||||
xfs_btree_set_refs(
|
||||
struct xfs_btree_cur *cur,
|
||||
struct xfs_buf *bp)
|
||||
{
|
||||
switch (cur->bc_btnum) {
|
||||
case XFS_BTNUM_BNO:
|
||||
case XFS_BTNUM_CNT:
|
||||
XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_MAP, XFS_ALLOC_BTREE_REF);
|
||||
break;
|
||||
case XFS_BTNUM_INO:
|
||||
XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_INOMAP, XFS_INO_BTREE_REF);
|
||||
break;
|
||||
case XFS_BTNUM_BMAP:
|
||||
XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_MAP, XFS_BMAP_BTREE_REF);
|
||||
break;
|
||||
default:
|
||||
ASSERT(0);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Read in the buffer at the given ptr and return the buffer and
|
||||
* the block pointer within the buffer.
|
||||
*/
|
||||
STATIC int
|
||||
xfs_btree_read_buf_block(
|
||||
struct xfs_btree_cur *cur,
|
||||
union xfs_btree_ptr *ptr,
|
||||
int level,
|
||||
int flags,
|
||||
struct xfs_btree_block **block,
|
||||
struct xfs_buf **bpp)
|
||||
{
|
||||
struct xfs_mount *mp = cur->bc_mp;
|
||||
xfs_daddr_t d;
|
||||
int error;
|
||||
|
||||
/* need to sort out how callers deal with failures first */
|
||||
ASSERT(!(flags & XFS_BUF_TRYLOCK));
|
||||
|
||||
d = xfs_btree_ptr_to_daddr(cur, ptr);
|
||||
error = xfs_trans_read_buf(mp, cur->bc_tp, mp->m_ddev_targp, d,
|
||||
mp->m_bsize, flags, bpp);
|
||||
if (error)
|
||||
return error;
|
||||
|
||||
ASSERT(*bpp != NULL);
|
||||
ASSERT(!XFS_BUF_GETERROR(*bpp));
|
||||
|
||||
xfs_btree_set_refs(cur, *bpp);
|
||||
*block = XFS_BUF_TO_BLOCK(*bpp);
|
||||
|
||||
error = xfs_btree_check_block(cur, *block, level, *bpp);
|
||||
if (error)
|
||||
xfs_trans_brelse(cur->bc_tp, *bpp);
|
||||
return error;
|
||||
}
|
||||
|
||||
/*
|
||||
* Increment cursor by one record at the level.
|
||||
* For nonzero levels the leaf-ward information is untouched.
|
||||
*/
|
||||
int /* error */
|
||||
xfs_btree_increment(
|
||||
struct xfs_btree_cur *cur,
|
||||
int level,
|
||||
int *stat) /* success/failure */
|
||||
{
|
||||
struct xfs_btree_block *block;
|
||||
union xfs_btree_ptr ptr;
|
||||
struct xfs_buf *bp;
|
||||
int error; /* error return value */
|
||||
int lev;
|
||||
|
||||
XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
|
||||
XFS_BTREE_TRACE_ARGI(cur, level);
|
||||
|
||||
ASSERT(level < cur->bc_nlevels);
|
||||
|
||||
/* Read-ahead to the right at this level. */
|
||||
xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA);
|
||||
|
||||
/* Get a pointer to the btree block. */
|
||||
block = xfs_btree_get_block(cur, level, &bp);
|
||||
|
||||
#ifdef DEBUG
|
||||
error = xfs_btree_check_block(cur, block, level, bp);
|
||||
if (error)
|
||||
goto error0;
|
||||
#endif
|
||||
|
||||
/* We're done if we remain in the block after the increment. */
|
||||
if (++cur->bc_ptrs[level] <= xfs_btree_get_numrecs(block))
|
||||
goto out1;
|
||||
|
||||
/* Fail if we just went off the right edge of the tree. */
|
||||
xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
|
||||
if (xfs_btree_ptr_is_null(cur, &ptr))
|
||||
goto out0;
|
||||
|
||||
XFS_BTREE_STATS_INC(cur, increment);
|
||||
|
||||
/*
|
||||
* March up the tree incrementing pointers.
|
||||
* Stop when we don't go off the right edge of a block.
|
||||
*/
|
||||
for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
|
||||
block = xfs_btree_get_block(cur, lev, &bp);
|
||||
|
||||
#ifdef DEBUG
|
||||
error = xfs_btree_check_block(cur, block, lev, bp);
|
||||
if (error)
|
||||
goto error0;
|
||||
#endif
|
||||
|
||||
if (++cur->bc_ptrs[lev] <= xfs_btree_get_numrecs(block))
|
||||
break;
|
||||
|
||||
/* Read-ahead the right block for the next loop. */
|
||||
xfs_btree_readahead(cur, lev, XFS_BTCUR_RIGHTRA);
|
||||
}
|
||||
|
||||
/*
|
||||
* If we went off the root then we are either seriously
|
||||
* confused or have the tree root in an inode.
|
||||
*/
|
||||
if (lev == cur->bc_nlevels) {
|
||||
if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE)
|
||||
goto out0;
|
||||
ASSERT(0);
|
||||
error = EFSCORRUPTED;
|
||||
goto error0;
|
||||
}
|
||||
ASSERT(lev < cur->bc_nlevels);
|
||||
|
||||
/*
|
||||
* Now walk back down the tree, fixing up the cursor's buffer
|
||||
* pointers and key numbers.
|
||||
*/
|
||||
for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
|
||||
union xfs_btree_ptr *ptrp;
|
||||
|
||||
ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
|
||||
error = xfs_btree_read_buf_block(cur, ptrp, --lev,
|
||||
0, &block, &bp);
|
||||
if (error)
|
||||
goto error0;
|
||||
|
||||
xfs_btree_setbuf(cur, lev, bp);
|
||||
cur->bc_ptrs[lev] = 1;
|
||||
}
|
||||
out1:
|
||||
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
|
||||
*stat = 1;
|
||||
return 0;
|
||||
|
||||
out0:
|
||||
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
|
||||
*stat = 0;
|
||||
return 0;
|
||||
|
||||
error0:
|
||||
XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
|
||||
return error;
|
||||
}
|
||||
|
||||
Reference in New Issue
Block a user