Merge v6.16.2linux-rolling-stable

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2 files changed, 62 insertions, 14 deletions

diff --git a/fs/squashfs/Kconfig b/fs/squashfs/Kconfig
index b1091e70434a..a9602aae21ef 100644
--- a/fs/squashfs/Kconfig
+++ b/fs/squashfs/Kconfig
@@ -149,6 +149,27 @@ config SQUASHFS_XATTR
 
 	  If unsure, say N.
 
+config SQUASHFS_COMP_CACHE_FULL
+	bool "Enable full caching of compressed blocks"
+	depends on SQUASHFS
+	default n
+	help
+	  This option enables caching of all compressed blocks, Without caching,
+	  repeated reads of the same files trigger excessive disk I/O, significantly
+	  reducinng performance in workloads like fio-based benchmarks.
+
+	  For example, fio tests (iodepth=1, numjobs=1, ioengine=psync) show:
+	   With caching: IOPS=2223, BW=278MiB/s (291MB/s)
+	   Without caching: IOPS=815, BW=102MiB/s (107MB/s)
+
+	  Enabling this option restores performance to pre-regression levels by
+	  caching all compressed blocks in the page cache, reducing disk I/O for
+	  repeated reads. However, this increases memory usage, which may be a
+	  concern in memory-constrained environments.
+
+	  Enable this option if your workload involves frequent repeated reads and
+	  memory usage is not a limiting factor. If unsure, say N.
+
 config SQUASHFS_ZLIB
 	bool "Include support for ZLIB compressed file systems"
 	depends on SQUASHFS
diff --git a/fs/squashfs/block.c b/fs/squashfs/block.c
index 2dc730800f44..e7a4649fc85c 100644
--- a/fs/squashfs/block.c
+++ b/fs/squashfs/block.c
@@ -80,19 +80,22 @@ static int squashfs_bio_read_cached(struct bio *fullbio,
 		struct address_space *cache_mapping, u64 index, int length,
 		u64 read_start, u64 read_end, int page_count)
 {
-	struct page *head_to_cache = NULL, *tail_to_cache = NULL;
+	struct folio *head_to_cache = NULL, *tail_to_cache = NULL;
 	struct block_device *bdev = fullbio->bi_bdev;
 	int start_idx = 0, end_idx = 0;
-	struct bvec_iter_all iter_all;
+	struct folio_iter fi;;
 	struct bio *bio = NULL;
-	struct bio_vec *bv;
 	int idx = 0;
 	int err = 0;
+#ifdef CONFIG_SQUASHFS_COMP_CACHE_FULL
+	struct folio **cache_folios = kmalloc_array(page_count,
+			sizeof(*cache_folios), GFP_KERNEL | __GFP_ZERO);
+#endif
 
-	bio_for_each_segment_all(bv, fullbio, iter_all) {
-		struct page *page = bv->bv_page;
+	bio_for_each_folio_all(fi, fullbio) {
+		struct folio *folio = fi.folio;
 
-		if (page->mapping == cache_mapping) {
+		if (folio->mapping == cache_mapping) {
 			idx++;
 			continue;
 		}
@@ -107,9 +110,14 @@ static int squashfs_bio_read_cached(struct bio *fullbio,
 		 * adjacent blocks.
 		 */
 		if (idx == 0 && index != read_start)
-			head_to_cache = page;
+			head_to_cache = folio;
 		else if (idx == page_count - 1 && index + length != read_end)
-			tail_to_cache = page;
+			tail_to_cache = folio;
+#ifdef CONFIG_SQUASHFS_COMP_CACHE_FULL
+		/* Cache all pages in the BIO for repeated reads */
+		else if (cache_folios)
+			cache_folios[idx] = folio;
+#endif
 
 		if (!bio || idx != end_idx) {
 			struct bio *new = bio_alloc_clone(bdev, fullbio,
@@ -141,28 +149,47 @@ static int squashfs_bio_read_cached(struct bio *fullbio,
 		return err;
 
 	if (head_to_cache) {
-		int ret = add_to_page_cache_lru(head_to_cache, cache_mapping,
+		int ret = filemap_add_folio(cache_mapping, head_to_cache,
 						read_start >> PAGE_SHIFT,
 						GFP_NOIO);
 
 		if (!ret) {
-			SetPageUptodate(head_to_cache);
-			unlock_page(head_to_cache);
+			folio_mark_uptodate(head_to_cache);
+			folio_unlock(head_to_cache);
 		}
 
 	}
 
 	if (tail_to_cache) {
-		int ret = add_to_page_cache_lru(tail_to_cache, cache_mapping,
+		int ret = filemap_add_folio(cache_mapping, tail_to_cache,
 						(read_end >> PAGE_SHIFT) - 1,
 						GFP_NOIO);
 
 		if (!ret) {
-			SetPageUptodate(tail_to_cache);
-			unlock_page(tail_to_cache);
+			folio_mark_uptodate(tail_to_cache);
+			folio_unlock(tail_to_cache);
 		}
 	}
 
+#ifdef CONFIG_SQUASHFS_COMP_CACHE_FULL
+	if (!cache_folios)
+		goto out;
+
+	for (idx = 0; idx < page_count; idx++) {
+		if (!cache_folios[idx])
+			continue;
+		int ret = filemap_add_folio(cache_mapping, cache_folios[idx],
+						(read_start >> PAGE_SHIFT) + idx,
+						GFP_NOIO);
+
+		if (!ret) {
+			folio_mark_uptodate(cache_folios[idx]);
+			folio_unlock(cache_folios[idx]);
+		}
+	}
+	kfree(cache_folios);
+out:
+#endif
 	return 0;
 }