6.15-stable review patch. If anyone has any objections, please let me know.
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From: Gao Xiang hsiangkao@linux.alibaba.com
commit 27917e8194f91dffd8b4825350c63cb68e98ce58 upstream.
Flush the D-cache before unlocking folios for compressed inodes, as they are dirtied during decompression.
Avoid calling flush_dcache_folio() on every CPU write, since it's more like playing whack-a-mole without real benefit.
It has no impact on x86 and arm64/risc-v: on x86, flush_dcache_folio() is a no-op, and on arm64/risc-v, PG_dcache_clean (PG_arch_1) is clear for new page cache folios. However, certain ARM boards are affected, as reported.
Fixes: 3883a79abd02 ("staging: erofs: introduce VLE decompression support") Closes: https://lore.kernel.org/r/c1e51e16-6cc6-49d0-a63e-4e9ff6c4dd53@pengutronix.d... Closes: https://lore.kernel.org/r/38d43fae-1182-4155-9c5b-ffc7382d9917@siemens.com Tested-by: Jan Kiszka jan.kiszka@siemens.com Tested-by: Stefan Kerkmann s.kerkmann@pengutronix.de Signed-off-by: Gao Xiang hsiangkao@linux.alibaba.com Link: https://lore.kernel.org/r/20250709034614.2780117-2-hsiangkao@linux.alibaba.c... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/erofs/data.c | 16 +++++++++++----- fs/erofs/decompressor.c | 12 ++++-------- fs/erofs/fileio.c | 4 ++-- fs/erofs/internal.h | 2 +- fs/erofs/zdata.c | 6 +++--- 5 files changed, 21 insertions(+), 19 deletions(-)
--- a/fs/erofs/data.c +++ b/fs/erofs/data.c @@ -213,9 +213,11 @@ int erofs_map_dev(struct super_block *sb
/* * bit 30: I/O error occurred on this folio + * bit 29: CPU has dirty data in D-cache (needs aliasing handling); * bit 0 - 29: remaining parts to complete this folio */ -#define EROFS_ONLINEFOLIO_EIO (1 << 30) +#define EROFS_ONLINEFOLIO_EIO 30 +#define EROFS_ONLINEFOLIO_DIRTY 29
void erofs_onlinefolio_init(struct folio *folio) { @@ -232,19 +234,23 @@ void erofs_onlinefolio_split(struct foli atomic_inc((atomic_t *)&folio->private); }
-void erofs_onlinefolio_end(struct folio *folio, int err) +void erofs_onlinefolio_end(struct folio *folio, int err, bool dirty) { int orig, v;
do { orig = atomic_read((atomic_t *)&folio->private); - v = (orig - 1) | (err ? EROFS_ONLINEFOLIO_EIO : 0); + DBG_BUGON(orig <= 0); + v = dirty << EROFS_ONLINEFOLIO_DIRTY; + v |= (orig - 1) | (!!err << EROFS_ONLINEFOLIO_EIO); } while (atomic_cmpxchg((atomic_t *)&folio->private, orig, v) != orig);
- if (v & ~EROFS_ONLINEFOLIO_EIO) + if (v & (BIT(EROFS_ONLINEFOLIO_DIRTY) - 1)) return; folio->private = 0; - folio_end_read(folio, !(v & EROFS_ONLINEFOLIO_EIO)); + if (v & BIT(EROFS_ONLINEFOLIO_DIRTY)) + flush_dcache_folio(folio); + folio_end_read(folio, !(v & BIT(EROFS_ONLINEFOLIO_EIO))); }
static int erofs_iomap_begin(struct inode *inode, loff_t offset, loff_t length, --- a/fs/erofs/decompressor.c +++ b/fs/erofs/decompressor.c @@ -301,13 +301,11 @@ static int z_erofs_transform_plain(struc cur = min(cur, rq->outputsize); if (cur && rq->out[0]) { kin = kmap_local_page(rq->in[nrpages_in - 1]); - if (rq->out[0] == rq->in[nrpages_in - 1]) { + if (rq->out[0] == rq->in[nrpages_in - 1]) memmove(kin + rq->pageofs_out, kin + pi, cur); - flush_dcache_page(rq->out[0]); - } else { + else memcpy_to_page(rq->out[0], rq->pageofs_out, kin + pi, cur); - } kunmap_local(kin); } rq->outputsize -= cur; @@ -325,14 +323,12 @@ static int z_erofs_transform_plain(struc po = (rq->pageofs_out + cur + pi) & ~PAGE_MASK; DBG_BUGON(no >= nrpages_out); cnt = min(insz - pi, PAGE_SIZE - po); - if (rq->out[no] == rq->in[ni]) { + if (rq->out[no] == rq->in[ni]) memmove(kin + po, kin + rq->pageofs_in + pi, cnt); - flush_dcache_page(rq->out[no]); - } else if (rq->out[no]) { + else if (rq->out[no]) memcpy_to_page(rq->out[no], po, kin + rq->pageofs_in + pi, cnt); - } pi += cnt; } while (pi < insz); kunmap_local(kin); --- a/fs/erofs/fileio.c +++ b/fs/erofs/fileio.c @@ -38,7 +38,7 @@ static void erofs_fileio_ki_complete(str } else { bio_for_each_folio_all(fi, &rq->bio) { DBG_BUGON(folio_test_uptodate(fi.folio)); - erofs_onlinefolio_end(fi.folio, ret); + erofs_onlinefolio_end(fi.folio, ret, false); } } bio_uninit(&rq->bio); @@ -158,7 +158,7 @@ io_retry: } cur += len; } - erofs_onlinefolio_end(folio, err); + erofs_onlinefolio_end(folio, err, false); return err; }
--- a/fs/erofs/internal.h +++ b/fs/erofs/internal.h @@ -389,7 +389,7 @@ int erofs_fiemap(struct inode *inode, st int erofs_map_blocks(struct inode *inode, struct erofs_map_blocks *map); void erofs_onlinefolio_init(struct folio *folio); void erofs_onlinefolio_split(struct folio *folio); -void erofs_onlinefolio_end(struct folio *folio, int err); +void erofs_onlinefolio_end(struct folio *folio, int err, bool dirty); struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid); int erofs_getattr(struct mnt_idmap *idmap, const struct path *path, struct kstat *stat, u32 request_mask, --- a/fs/erofs/zdata.c +++ b/fs/erofs/zdata.c @@ -1060,7 +1060,7 @@ static int z_erofs_scan_folio(struct z_e tight = (bs == PAGE_SIZE); } } while ((end = cur) > 0); - erofs_onlinefolio_end(folio, err); + erofs_onlinefolio_end(folio, err, false); return err; }
@@ -1165,7 +1165,7 @@ static void z_erofs_fill_other_copies(st cur += len; } kunmap_local(dst); - erofs_onlinefolio_end(page_folio(bvi->bvec.page), err); + erofs_onlinefolio_end(page_folio(bvi->bvec.page), err, true); list_del(p); kfree(bvi); } @@ -1324,7 +1324,7 @@ static int z_erofs_decompress_pcluster(s
DBG_BUGON(z_erofs_page_is_invalidated(page)); if (!z_erofs_is_shortlived_page(page)) { - erofs_onlinefolio_end(page_folio(page), err); + erofs_onlinefolio_end(page_folio(page), err, true); continue; } if (pcl->algorithmformat != Z_EROFS_COMPRESSION_LZ4) {