xfs: refactor xfs_iwalk_grab_ichunk

In preparation for reusing the iwalk code for the inogrp walking code
(aka INUMBERS), move the initial inobt lookup and retrieval code out of
xfs_iwalk_grab_ichunk so that we call the masking code only when we need
to trim out the inodes that came before the cursor in the inobt record
(aka BULKSTAT).

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
This commit is contained in:
Darrick J. Wong 2019-07-02 09:39:42 -07:00
parent 688f7c3678
commit 2b5eb82601

View File

@ -98,43 +98,17 @@ xfs_iwalk_ichunk_ra(
}
/*
* Lookup the inode chunk that the given @agino lives in and then get the
* record if we found the chunk. Set the bits in @irec's free mask that
* correspond to the inodes before @agino so that we skip them. This is how we
* restart an inode walk that was interrupted in the middle of an inode record.
* Set the bits in @irec's free mask that correspond to the inodes before
* @agino so that we skip them. This is how we restart an inode walk that was
* interrupted in the middle of an inode record.
*/
STATIC int
xfs_iwalk_grab_ichunk(
struct xfs_btree_cur *cur, /* btree cursor */
STATIC void
xfs_iwalk_adjust_start(
xfs_agino_t agino, /* starting inode of chunk */
int *icount,/* return # of inodes grabbed */
struct xfs_inobt_rec_incore *irec) /* btree record */
{
int idx; /* index into inode chunk */
int stat;
int i;
int error = 0;
/* Lookup the inode chunk that this inode lives in */
error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &stat);
if (error)
return error;
if (!stat) {
*icount = 0;
return error;
}
/* Get the record, should always work */
error = xfs_inobt_get_rec(cur, irec, &stat);
if (error)
return error;
XFS_WANT_CORRUPTED_RETURN(cur->bc_mp, stat == 1);
/* Check if the record contains the inode in request */
if (irec->ir_startino + XFS_INODES_PER_CHUNK <= agino) {
*icount = 0;
return 0;
}
idx = agino - irec->ir_startino;
@ -149,8 +123,6 @@ xfs_iwalk_grab_ichunk(
}
irec->ir_free |= xfs_inobt_maskn(0, idx);
*icount = irec->ir_count - irec->ir_freecount;
return 0;
}
/* Allocate memory for a walk. */
@ -259,7 +231,7 @@ xfs_iwalk_ag_start(
{
struct xfs_mount *mp = iwag->mp;
struct xfs_trans *tp = iwag->tp;
int icount;
struct xfs_inobt_rec_incore *irec;
int error;
/* Set up a fresh cursor and empty the inobt cache. */
@ -275,15 +247,40 @@ xfs_iwalk_ag_start(
/*
* Otherwise, we have to grab the inobt record where we left off, stuff
* the record into our cache, and then see if there are more records.
* We require a lookup cache of at least two elements so that we don't
* have to deal with tearing down the cursor to walk the records.
* We require a lookup cache of at least two elements so that the
* caller doesn't have to deal with tearing down the cursor to walk the
* records.
*/
error = xfs_iwalk_grab_ichunk(*curpp, agino, &icount,
&iwag->recs[iwag->nr_recs]);
error = xfs_inobt_lookup(*curpp, agino, XFS_LOOKUP_LE, has_more);
if (error)
return error;
if (icount)
iwag->nr_recs++;
/*
* If the LE lookup at @agino yields no records, jump ahead to the
* inobt cursor increment to see if there are more records to process.
*/
if (!*has_more)
goto out_advance;
/* Get the record, should always work */
irec = &iwag->recs[iwag->nr_recs];
error = xfs_inobt_get_rec(*curpp, irec, has_more);
if (error)
return error;
XFS_WANT_CORRUPTED_RETURN(mp, *has_more == 1);
/*
* If the LE lookup yielded an inobt record before the cursor position,
* skip it and see if there's another one after it.
*/
if (irec->ir_startino + XFS_INODES_PER_CHUNK <= agino)
goto out_advance;
/*
* If agino fell in the middle of the inode record, make it look like
* the inodes up to agino are free so that we don't return them again.
*/
xfs_iwalk_adjust_start(agino, irec);
/*
* The prefetch calculation is supposed to give us a large enough inobt
@ -291,8 +288,10 @@ xfs_iwalk_ag_start(
* the loop body can cache a record without having to check for cache
* space until after it reads an inobt record.
*/
iwag->nr_recs++;
ASSERT(iwag->nr_recs < iwag->sz_recs);
out_advance:
return xfs_btree_increment(*curpp, 0, has_more);
}