[38/41] xfs: pass the exact range to initialize to xfs_initialize_perag

Commit Message

Darrick J. Wong Oct. 31, 2024, 11:18 p.m. UTC

From: Christoph Hellwig <[e-mail]>

Source kernel commit: 82742f8c3f1a93787a05a00aca50c2a565231f84

Currently only the new agcount is passed to xfs_initialize_perag, which
requires lookups of existing AGs to skip them and complicates error
handling.  Also pass the previous agcount so that the range that
xfs_initialize_perag operates on is exactly defined.  That way the
extra lookups can be avoided, and error handling can clean up the
exact range from the old count to the last added perag structure.

Signed-off-by: Christoph Hellwig <[e-mail]>
Reviewed-by: Darrick J. Wong <[e-mail]>
Reviewed-by: Brian Foster <[e-mail]>
Signed-off-by: Carlos Maiolino <[e-mail]>
---
 libxfs/xfs_ag.c |   28 ++++++----------------------
 libxfs/xfs_ag.h |    5 +++--
 2 files changed, 9 insertions(+), 24 deletions(-)

Patch

diff --git a/libxfs/xfs_ag.c b/libxfs/xfs_ag.c
index 516c76790cc0d8..3bbfefe5e46935 100644
--- a/libxfs/xfs_ag.c
+++ b/libxfs/xfs_ag.c
@@ -294,27 +294,16 @@  xfs_free_unused_perag_range(
 int
 xfs_initialize_perag(
 	struct xfs_mount	*mp,
-	xfs_agnumber_t		agcount,
+	xfs_agnumber_t		old_agcount,
+	xfs_agnumber_t		new_agcount,
 	xfs_rfsblock_t		dblocks,
 	xfs_agnumber_t		*maxagi)
 {
 	struct xfs_perag	*pag;
 	xfs_agnumber_t		index;
-	xfs_agnumber_t		first_initialised = NULLAGNUMBER;
 	int			error;
 
-	/*
-	 * Walk the current per-ag tree so we don't try to initialise AGs
-	 * that already exist (growfs case). Allocate and insert all the
-	 * AGs we don't find ready for initialisation.
-	 */
-	for (index = 0; index < agcount; index++) {
-		pag = xfs_perag_get(mp, index);
-		if (pag) {
-			xfs_perag_put(pag);
-			continue;
-		}
-
+	for (index = old_agcount; index < new_agcount; index++) {
 		pag = kzalloc(sizeof(*pag), GFP_KERNEL | __GFP_RETRY_MAYFAIL);
 		if (!pag) {
 			error = -ENOMEM;
@@ -351,21 +340,17 @@  xfs_initialize_perag(
 		/* Active ref owned by mount indicates AG is online. */
 		atomic_set(&pag->pag_active_ref, 1);
 
-		/* first new pag is fully initialized */
-		if (first_initialised == NULLAGNUMBER)
-			first_initialised = index;
-
 		/*
 		 * Pre-calculated geometry
 		 */
-		pag->block_count = __xfs_ag_block_count(mp, index, agcount,
+		pag->block_count = __xfs_ag_block_count(mp, index, new_agcount,
 				dblocks);
 		pag->min_block = XFS_AGFL_BLOCK(mp);
 		__xfs_agino_range(mp, pag->block_count, &pag->agino_min,
 				&pag->agino_max);
 	}
 
-	index = xfs_set_inode_alloc(mp, agcount);
+	index = xfs_set_inode_alloc(mp, new_agcount);
 
 	if (maxagi)
 		*maxagi = index;
@@ -379,8 +364,7 @@  xfs_initialize_perag(
 out_free_pag:
 	kfree(pag);
 out_unwind_new_pags:
-	/* unwind any prior newly initialized pags */
-	xfs_free_unused_perag_range(mp, first_initialised, agcount);
+	xfs_free_unused_perag_range(mp, old_agcount, index);
 	return error;
 }
 
diff --git a/libxfs/xfs_ag.h b/libxfs/xfs_ag.h
index d9cccd093b60e0..69fc31e7b84728 100644
--- a/libxfs/xfs_ag.h
+++ b/libxfs/xfs_ag.h
@@ -146,8 +146,9 @@  __XFS_AG_OPSTATE(agfl_needs_reset, AGFL_NEEDS_RESET)
 
 void xfs_free_unused_perag_range(struct xfs_mount *mp, xfs_agnumber_t agstart,
 			xfs_agnumber_t agend);
-int xfs_initialize_perag(struct xfs_mount *mp, xfs_agnumber_t agcount,
-			xfs_rfsblock_t dcount, xfs_agnumber_t *maxagi);
+int xfs_initialize_perag(struct xfs_mount *mp, xfs_agnumber_t old_agcount,
+		xfs_agnumber_t agcount, xfs_rfsblock_t dcount,
+		xfs_agnumber_t *maxagi);
 int xfs_initialize_perag_data(struct xfs_mount *mp, xfs_agnumber_t agno);
 void xfs_free_perag(struct xfs_mount *mp);