From 846b730e99518a1c9945afcb2afbe4d08a02ed80 Mon Sep 17 00:00:00 2001 From: Phillip Lougher Date: Mon, 18 Nov 2013 02:59:12 +0000 Subject: Squashfs: Generalise paging handling in the decompressors Further generalise the decompressors by adding a page handler abstraction. This adds helpers to allow the decompressors to access and process the output buffers in an implementation independant manner. This allows different types of output buffer to be passed to the decompressors, with the implementation specific aspects handled at decompression time, but without the knowledge being held in the decompressor wrapper code. This will allow the decompressors to handle Squashfs cache buffers, and page cache pages. This patch adds the abstraction and an implementation for the caches. Signed-off-by: Phillip Lougher Reviewed-by: Minchan Kim --- fs/squashfs/decompressor.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) (limited to 'fs/squashfs/decompressor.c') diff --git a/fs/squashfs/decompressor.c b/fs/squashfs/decompressor.c index 234291f79ba5..ac22fe73b0ad 100644 --- a/fs/squashfs/decompressor.c +++ b/fs/squashfs/decompressor.c @@ -30,6 +30,7 @@ #include "squashfs_fs_sb.h" #include "decompressor.h" #include "squashfs.h" +#include "page_actor.h" /* * This file (and decompressor.h) implements a decompressor framework for @@ -87,6 +88,7 @@ static void *get_comp_opts(struct super_block *sb, unsigned short flags) { struct squashfs_sb_info *msblk = sb->s_fs_info; void *buffer = NULL, *comp_opts; + struct squashfs_page_actor *actor = NULL; int length = 0; /* @@ -99,9 +101,14 @@ static void *get_comp_opts(struct super_block *sb, unsigned short flags) goto out; } - length = squashfs_read_data(sb, &buffer, - sizeof(struct squashfs_super_block), 0, NULL, - PAGE_CACHE_SIZE, 1); + actor = squashfs_page_actor_init(&buffer, 1, 0); + if (actor == NULL) { + comp_opts = ERR_PTR(-ENOMEM); + goto out; + } + + length = squashfs_read_data(sb, + sizeof(struct squashfs_super_block), 0, NULL, actor); if (length < 0) { comp_opts = ERR_PTR(length); @@ -112,6 +119,7 @@ static void *get_comp_opts(struct super_block *sb, unsigned short flags) comp_opts = squashfs_comp_opts(msblk, buffer, length); out: + kfree(actor); kfree(buffer); return comp_opts; } -- cgit v1.2.3