[PATCH 5/7] iomap: limit buffered I/O size to 128M
From: Christoph Hellwig <hch@lst.de>
Date: 2025-02-03 09:43:39
Also in:
linux-fsdevel, linux-xfs
Subsystem:
filesystems (vfs and infrastructure), filesystems [iomap], the rest · Maintainers:
Alexander Viro, Christian Brauner, Linus Torvalds
Currently iomap can build extremely large bios (I've seen sizes up to 480MB). Limit this to a lower bound so that the soon to be added per-ioend integrity buffer doesn't go beyond what the page allocator can support. Signed-off-by: Christoph Hellwig <hch@lst.de> --- fs/iomap/buffered-io.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 06990e012884..71bb676d4998 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c@@ -456,6 +456,7 @@ static loff_t iomap_readpage_iter(const struct iomap_iter *iter, sector = iomap_sector(iomap, pos); if (!ctx->bio || bio_end_sector(ctx->bio) != sector || + ctx->bio->bi_iter.bi_size > SZ_128M || !bio_add_folio(ctx->bio, folio, plen, poff)) { if (ctx->bio) iomap_read_submit_bio(iter, ctx);
@@ -1674,6 +1675,8 @@ static struct iomap_ioend *iomap_alloc_ioend(struct iomap_writepage_ctx *wpc, static bool iomap_can_add_to_ioend(struct iomap_writepage_ctx *wpc, loff_t pos, u16 ioend_flags) { + if (wpc->ioend->io_bio.bi_iter.bi_size > SZ_128M) + return false; if (ioend_flags & IOMAP_IOEND_BOUNDARY) return false; if ((ioend_flags & IOMAP_IOEND_NOMERGE_FLAGS) !=
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2.45.2