[PATCH 04/24] xfs: factor out a xfs_rtallocate_align helper

Darrick J. Wong
2024-08-23T00:15:42Z

From: Christoph Hellwig <hch@lst.de>

Split the code to calculate the aligned allocation request from
xfs_bmap_rtalloc into a separate self-contained helper.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
fs/xfs/xfs_rtalloc.c | 93 ++++++++++++++++++++++++++++++++------------------
1 file changed, 59 insertions(+), 34 deletions(-)

diff --git a/fs/xfs/xfs_rtalloc.c b/fs/xfs/xfs_rtalloc.c
index f39f05397201a..7f20bc412d074 100644
--- a/fs/xfs/xfs_rtalloc.c
+++ b/fs/xfs/xfs_rtalloc.c
@@ -1342,30 +1342,33 @@ xfs_rtallocate(
return error;
}

-int
-xfs_bmap_rtalloc(
- struct xfs_bmalloca *ap)
+static int
+xfs_rtallocate_align(
+ struct xfs_bmalloca *ap,
+ xfs_rtxlen_t *ralen,
+ xfs_rtxlen_t *raminlen,
+ xfs_rtxlen_t *prod,
+ bool *noalign)
{
struct xfs_mount *mp = ap->ip->i_mount;
xfs_fileoff_t orig_offset = ap->offset;
- xfs_rtxnum_t start = 0; /* allocation hint rtextent no */
- xfs_rtxlen_t prod = 0; /* product factor for allocators */
- xfs_extlen_t mod = 0; /* product factor for allocators */
- xfs_rtxlen_t ralen = 0; /* realtime allocation length */
- xfs_extlen_t align; /* minimum allocation alignment */
- xfs_extlen_t orig_length = ap->length;
xfs_extlen_t minlen = mp->m_sb.sb_rextsize;
- xfs_rtxlen_t raminlen;
- bool rtlocked = false;
+ xfs_extlen_t align; /* minimum allocation alignment */
+ xfs_extlen_t mod; /* product factor for allocators */
int error;

- align = xfs_get_extsz_hint(ap->ip);
- if (!align)
- align = 1;
-retry:
- error = xfs_bmap_extsize_align(mp, &ap->got, &ap->prev,
- align, 1, ap->eof, 0,
- ap->conv, &ap->offset, &ap->length);
+ if (*noalign) {
+ align = mp->m_sb.sb_rextsize;
+ } else {
+ align = xfs_get_extsz_hint(ap->ip);
+ if (!align)
+ align = 1;
+ if (align == mp->m_sb.sb_rextsize)
+ *noalign = true;
+ }
+
+ error = xfs_bmap_extsize_align(mp, &ap->got, &ap->prev, align, 1,
+ ap->eof, 0, ap->conv, &ap->offset, &ap->length);
if (error)
return error;
ASSERT(ap->length);
@@ -1389,32 +1392,54 @@ xfs_bmap_rtalloc(
* XFS_BMBT_MAX_EXTLEN), we don't hear about that number, and can't
* adjust the starting point to match it.
*/
- ralen = xfs_extlen_to_rtxlen(mp, min(ap->length, XFS_MAX_BMBT_EXTLEN));
- raminlen = max_t(xfs_rtxlen_t, 1, xfs_extlen_to_rtxlen(mp, minlen));
- ASSERT(raminlen > 0);
- ASSERT(raminlen <= ralen);
-
- if (xfs_bmap_adjacent(ap))
- start = xfs_rtb_to_rtx(mp, ap->blkno);
+ *ralen = xfs_extlen_to_rtxlen(mp, min(ap->length, XFS_MAX_BMBT_EXTLEN));
+ *raminlen = max_t(xfs_rtxlen_t, 1, xfs_extlen_to_rtxlen(mp, minlen));
+ ASSERT(*raminlen > 0);
+ ASSERT(*raminlen <= *ralen);

/*
* Only bother calculating a real prod factor if offset & length are
* perfectly aligned, otherwise it will just get us in trouble.
*/
div_u64_rem(ap->offset, align, &mod);
- if (mod || ap->length % align) {
- prod = 1;
- } else {
- prod = xfs_extlen_to_rtxlen(mp, align);
- if (prod > 1)
- xfs_rtalloc_align_minmax(&raminlen, &ralen, &prod);
- }
+ if (mod || ap->length % align)
+ *prod = 1;
+ else
+ *prod = xfs_extlen_to_rtxlen(mp, align);
+
+ if (*prod > 1)
+ xfs_rtalloc_align_minmax(raminlen, ralen, prod);
+ return 0;
+}
+
+int
+xfs_bmap_rtalloc(
+ struct xfs_bmalloca *ap)
+{
+ struct xfs_mount *mp = ap->ip->i_mount;
+ xfs_fileoff_t orig_offset = ap->offset;
+ xfs_rtxnum_t start = 0; /* allocation hint rtextent no */
+ xfs_rtxlen_t prod = 0; /* product factor for allocators */
+ xfs_rtxlen_t ralen = 0; /* realtime allocation length */
+ xfs_extlen_t orig_length = ap->length;
+ xfs_rtxlen_t raminlen;
+ bool rtlocked = false;
+ bool noalign = false;
+ int error;
+
+retry:
+ error = xfs_rtallocate_align(ap, &ralen, &raminlen, &prod, &noalign);
+ if (error)
+ return error;
+
+ if (xfs_bmap_adjacent(ap))
+ start = xfs_rtb_to_rtx(mp, ap->blkno);

error = xfs_rtallocate(ap->tp, start, raminlen, ralen, prod, ap->wasdel,
ap->datatype & XFS_ALLOC_INITIAL_USER_DATA, &rtlocked,
&ap->blkno, &ap->length);
if (error == -ENOSPC) {
- if (align > mp->m_sb.sb_rextsize) {
+ if (!noalign) {
/*
* We previously enlarged the request length to try to
* satisfy an extent size hint. The allocator didn't
@@ -1424,7 +1449,7 @@ xfs_bmap_rtalloc(
*/
ap->offset = orig_offset;
ap->length = orig_length;
- minlen = align = mp->m_sb.sb_rextsize;
+ noalign = true;
goto retry;
}