From 49ff29240ebb13bc0efa4623d4379650e68fcb35 Mon Sep 17 00:00:00 2001 From: Phillip Lougher Date: Sun, 29 Dec 2024 23:37:49 +0000 Subject: [PATCH] squashfs: make squashfs_cache_init() return ERR_PTR(-ENOMEM) Patch series "squashfs: reduce memory usage and update docs". This patchset reduces the amount of memory that Squashfs uses when CONFIG_FILE_DIRECT is configured, and updates various out of date information in the documentation and Kconfig. This patch (of 4): Make squashfs_cache_init() return an ERR_PTR(-ENOMEM) on failure rather than NULL. This tidies up some calling code, but, it also allows NULL to be returned as a valid result when a cache hasn't be allocated. Link: https://lkml.kernel.org/r/20241229233752.54481-1-phillip@squashfs.org.uk Link: https://lkml.kernel.org/r/20241229233752.54481-2-phillip@squashfs.org.uk Signed-off-by: Phillip Lougher Signed-off-by: Andrew Morton --- fs/squashfs/cache.c | 10 +++++++--- fs/squashfs/super.c | 17 ++++++++++------- 2 files changed, 17 insertions(+), 10 deletions(-) diff --git a/fs/squashfs/cache.c b/fs/squashfs/cache.c index 5062326d0efb..4db0d2b0aab8 100644 --- a/fs/squashfs/cache.c +++ b/fs/squashfs/cache.c @@ -224,11 +224,15 @@ struct squashfs_cache *squashfs_cache_init(char *name, int entries, int block_size) { int i, j; - struct squashfs_cache *cache = kzalloc(sizeof(*cache), GFP_KERNEL); + struct squashfs_cache *cache; + if (entries == 0) + return NULL; + + cache = kzalloc(sizeof(*cache), GFP_KERNEL); if (cache == NULL) { ERROR("Failed to allocate %s cache\n", name); - return NULL; + return ERR_PTR(-ENOMEM); } cache->entry = kcalloc(entries, sizeof(*(cache->entry)), GFP_KERNEL); @@ -281,7 +285,7 @@ struct squashfs_cache *squashfs_cache_init(char *name, int entries, cleanup: squashfs_cache_delete(cache); - return NULL; + return ERR_PTR(-ENOMEM); } diff --git a/fs/squashfs/super.c b/fs/squashfs/super.c index 269c6d61bc29..fedae8dbc5de 100644 --- a/fs/squashfs/super.c +++ b/fs/squashfs/super.c @@ -314,26 +314,29 @@ static int squashfs_fill_super(struct super_block *sb, struct fs_context *fc) sb->s_flags |= SB_RDONLY; sb->s_op = &squashfs_super_ops; - err = -ENOMEM; - msblk->block_cache = squashfs_cache_init("metadata", SQUASHFS_CACHED_BLKS, SQUASHFS_METADATA_SIZE); - if (msblk->block_cache == NULL) + if (IS_ERR(msblk->block_cache)) { + err = PTR_ERR(msblk->block_cache); goto failed_mount; + } /* Allocate read_page block */ msblk->read_page = squashfs_cache_init("data", msblk->max_thread_num, msblk->block_size); - if (msblk->read_page == NULL) { + if (IS_ERR(msblk->read_page)) { errorf(fc, "Failed to allocate read_page block"); + err = PTR_ERR(msblk->read_page); goto failed_mount; } if (msblk->devblksize == PAGE_SIZE) { struct inode *cache = new_inode(sb); - if (cache == NULL) + if (cache == NULL) { + err = -ENOMEM; goto failed_mount; + } set_nlink(cache, 1); cache->i_size = OFFSET_MAX; @@ -406,8 +409,8 @@ handle_fragments: msblk->fragment_cache = squashfs_cache_init("fragment", min(SQUASHFS_CACHED_FRAGMENTS, fragments), msblk->block_size); - if (msblk->fragment_cache == NULL) { - err = -ENOMEM; + if (IS_ERR(msblk->fragment_cache)) { + err = PTR_ERR(msblk->fragment_cache); goto failed_mount; } -- 2.50.1