[PATCH 17/22] xfs: simplify xfs_dialloc_select_ag() return values

Dave Chinner
2021-05-06T07:21:02Z

From: Dave Chinner <dchinner@redhat.com>

The only caller of xfs_dialloc_select_ag() will always return
-ENOSPC to it's caller if the agbp returned from
xfs_dialloc_select_ag() is NULL. IOWs, failure to find a candidate
AGI we can allocate inodes from is always an ENOSPC condition, so
move this logic up into xfs_dialloc_select_ag() so we can simplify
the return logic in this function.

xfs_dialloc_select_ag() now only ever returns 0 with a locked
agbp, or an error with no agbp.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
---
fs/xfs/libxfs/xfs_ialloc.c | 23 ++++++++---------------
fs/xfs/xfs_inode.c | 3 ---
2 files changed, 8 insertions(+), 18 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_ialloc.c b/fs/xfs/libxfs/xfs_ialloc.c
index 4540fbcd68a3..872591e8f5cb 100644
--- a/fs/xfs/libxfs/xfs_ialloc.c
+++ b/fs/xfs/libxfs/xfs_ialloc.c
@@ -1717,7 +1717,7 @@ xfs_dialloc_roll(
* This function will ensure that the selected AG has free inodes available to
* allocate from. The selected AGI will be returned locked to the caller, and it
* will allocate more free inodes if required. If no free inodes are found or
- * can be allocated, no AGI will be returned.
+ * can be allocated, -ENOSPC be returned.
*/
int
xfs_dialloc_select_ag(
@@ -1730,7 +1730,6 @@ xfs_dialloc_select_ag(
struct xfs_buf *agbp;
xfs_agnumber_t agno;
int error;
- bool noroom = false;
xfs_agnumber_t start_agno;
struct xfs_perag *pag;
struct xfs_ino_geometry *igeo = M_IGEO(mp);
@@ -1744,7 +1743,7 @@ xfs_dialloc_select_ag(
*/
start_agno = xfs_ialloc_ag_select(*tpp, parent, mode);
if (start_agno == NULLAGNUMBER)
- return 0;
+ return -ENOSPC;

/*
* If we have already hit the ceiling of inode blocks then clear
@@ -1757,7 +1756,6 @@ xfs_dialloc_select_ag(
if (igeo->maxicount &&
percpu_counter_read_positive(&mp->m_icount) + igeo->ialloc_inos
> igeo->maxicount) {
- noroom = true;
okalloc = false;
}

@@ -1794,10 +1792,8 @@ xfs_dialloc_select_ag(
if (error)
break;

- if (pag->pagi_freecount) {
- xfs_perag_put(pag);
+ if (pag->pagi_freecount)
goto found_ag;
- }

if (!okalloc)
goto nextag_relse_buffer;
@@ -1805,9 +1801,6 @@ xfs_dialloc_select_ag(
error = xfs_ialloc_ag_alloc(*tpp, agbp, pag);
if (error < 0) {
xfs_trans_brelse(*tpp, agbp);
-
- if (error == -ENOSPC)
- error = 0;
break;
}

@@ -1818,12 +1811,11 @@ xfs_dialloc_select_ag(
* allocate one of the new inodes.
*/
ASSERT(pag->pagi_freecount > 0);
- xfs_perag_put(pag);

error = xfs_dialloc_roll(tpp, agbp);
if (error) {
xfs_buf_relse(agbp);
- return error;
+ break;
}
goto found_ag;
}
@@ -1831,16 +1823,17 @@ xfs_dialloc_select_ag(
nextag_relse_buffer:
xfs_trans_brelse(*tpp, agbp);
nextag:
- xfs_perag_put(pag);
if (++agno == mp->m_sb.sb_agcount)
agno = 0;
if (agno == start_agno)
- return noroom ? -ENOSPC : 0;
+ break;
+ xfs_perag_put(pag);
}

xfs_perag_put(pag);
- return error;
+ return error ? error : -ENOSPC;
found_ag:
+ xfs_perag_put(pag);
*IO_agbp = agbp;
return 0;
}
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 25910b145d70..3918c99fa95b 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -923,9 +923,6 @@ xfs_dir_ialloc(
if (error)
return error;

- if (!agibp)
- return -ENOSPC;
-
/* Allocate an inode from the selected AG */
error = xfs_dialloc_ag(*tpp, agibp, parent_ino, &ino);
if (error)
--
2.31.1