Squashfs: factor out remaining zlib dependencies into separate wrapper file

Move zlib buffer init/destroy code into separate wrapper file.  Also
make zlib z_stream field a void * removing the need to include zlib.h
for most files.

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>

14 files changed, 51 insertions, 33 deletions

diff --git a/fs/squashfs/block.c b/fs/squashfs/block.c
index b8addfdc6094..3f836e181eb8 100644
--- a/fs/squashfs/block.c
+++ b/fs/squashfs/block.c
@@ -31,7 +31,6 @@
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/buffer_head.h>
-#include <linux/zlib.h>
 
 #include "squashfs_fs.h"
 #include "squashfs_fs_sb.h"
diff --git a/fs/squashfs/cache.c b/fs/squashfs/cache.c
index 40c98fa6b5d6..57314bee9059 100644
--- a/fs/squashfs/cache.c
+++ b/fs/squashfs/cache.c
@@ -51,7 +51,6 @@
 #include <linux/sched.h>
 #include <linux/spinlock.h>
 #include <linux/wait.h>
-#include <linux/zlib.h>
 #include <linux/pagemap.h>
 
 #include "squashfs_fs.h"
diff --git a/fs/squashfs/dir.c b/fs/squashfs/dir.c
index 566b0eaed868..12b933ac6585 100644
--- a/fs/squashfs/dir.c
+++ b/fs/squashfs/dir.c
@@ -30,7 +30,6 @@
 #include <linux/fs.h>
 #include <linux/vfs.h>
 #include <linux/slab.h>
-#include <linux/zlib.h>
 
 #include "squashfs_fs.h"
 #include "squashfs_fs_sb.h"
diff --git a/fs/squashfs/export.c b/fs/squashfs/export.c
index 2b1b8fe5e037..7f93d5a9ee05 100644
--- a/fs/squashfs/export.c
+++ b/fs/squashfs/export.c
@@ -39,7 +39,6 @@
 #include <linux/vfs.h>
 #include <linux/dcache.h>
 #include <linux/exportfs.h>
-#include <linux/zlib.h>
 #include <linux/slab.h>
 
 #include "squashfs_fs.h"
diff --git a/fs/squashfs/file.c b/fs/squashfs/file.c
index 717767d831df..a25c5060bdcb 100644
--- a/fs/squashfs/file.c
+++ b/fs/squashfs/file.c
@@ -47,7 +47,6 @@
 #include <linux/string.h>
 #include <linux/pagemap.h>
 #include <linux/mutex.h>
-#include <linux/zlib.h>
 
 #include "squashfs_fs.h"
 #include "squashfs_fs_sb.h"
diff --git a/fs/squashfs/fragment.c b/fs/squashfs/fragment.c
index b5a2c15bbbc7..7c90bbd6879d 100644
--- a/fs/squashfs/fragment.c
+++ b/fs/squashfs/fragment.c
@@ -36,7 +36,6 @@
 #include <linux/fs.h>
 #include <linux/vfs.h>
 #include <linux/slab.h>
-#include <linux/zlib.h>
 
 #include "squashfs_fs.h"
 #include "squashfs_fs_sb.h"
diff --git a/fs/squashfs/id.c b/fs/squashfs/id.c
index 3795b837ba28..b7f64bcd2b70 100644
--- a/fs/squashfs/id.c
+++ b/fs/squashfs/id.c
@@ -34,7 +34,6 @@
 #include <linux/fs.h>
 #include <linux/vfs.h>
 #include <linux/slab.h>
-#include <linux/zlib.h>
 
 #include "squashfs_fs.h"
 #include "squashfs_fs_sb.h"
diff --git a/fs/squashfs/inode.c b/fs/squashfs/inode.c
index 9101dbde39ec..49daaf669e41 100644
--- a/fs/squashfs/inode.c
+++ b/fs/squashfs/inode.c
@@ -40,7 +40,6 @@
 
 #include <linux/fs.h>
 #include <linux/vfs.h>
-#include <linux/zlib.h>
 
 #include "squashfs_fs.h"
 #include "squashfs_fs_sb.h"
diff --git a/fs/squashfs/namei.c b/fs/squashfs/namei.c
index 9e398653b22b..5266bd8ad932 100644
--- a/fs/squashfs/namei.c
+++ b/fs/squashfs/namei.c
@@ -57,7 +57,6 @@
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/dcache.h>
-#include <linux/zlib.h>
 
 #include "squashfs_fs.h"
 #include "squashfs_fs_sb.h"
diff --git a/fs/squashfs/squashfs.h b/fs/squashfs/squashfs.h
index ba87db693651..9c2f76a1c50b 100644
--- a/fs/squashfs/squashfs.h
+++ b/fs/squashfs/squashfs.h
@@ -71,6 +71,8 @@ extern struct inode *squashfs_iget(struct super_block *, long long,
 extern int squashfs_read_inode(struct inode *, long long);
 
 /* zlib_wrapper.c */
+extern void *squashfs_zlib_init(void);
+extern void squashfs_zlib_free(void *);
 extern int squashfs_zlib_uncompress(struct squashfs_sb_info *, void **,
                                 struct buffer_head **, int, int, int, int, int);
 
diff --git a/fs/squashfs/squashfs_fs_sb.h b/fs/squashfs/squashfs_fs_sb.h
index c8c65614dd1c..23a67fa40b03 100644
--- a/fs/squashfs/squashfs_fs_sb.h
+++ b/fs/squashfs/squashfs_fs_sb.h
@@ -64,7 +64,7 @@ struct squashfs_sb_info {
         struct mutex            read_data_mutex;
         struct mutex            meta_index_mutex;
         struct meta_index       *meta_index;
-        z_stream                stream;
+        void                    *stream;
         __le64                  *inode_lookup_table;
         u64                     inode_table;
         u64                     directory_table;
diff --git a/fs/squashfs/super.c b/fs/squashfs/super.c
index 6c197ef53add..b9f8c6a92d6a 100644
--- a/fs/squashfs/super.c
+++ b/fs/squashfs/super.c
@@ -35,7 +35,6 @@
 #include <linux/pagemap.h>
 #include <linux/init.h>
 #include <linux/module.h>
-#include <linux/zlib.h>
 #include <linux/magic.h>
 
 #include "squashfs_fs.h"
@@ -87,12 +86,9 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
         }
         msblk = sb->s_fs_info;
 
-        msblk->stream.workspace = kmalloc(zlib_inflate_workspacesize(),
-                GFP_KERNEL);
-        if (msblk->stream.workspace == NULL) {
-                ERROR("Failed to allocate zlib workspace\n");
+        msblk->stream = squashfs_zlib_init();
+        if (msblk->stream == NULL)
                 goto failure;
-        }
 
         sblk = kzalloc(sizeof(*sblk), GFP_KERNEL);
         if (sblk == NULL) {
@@ -292,17 +288,17 @@ failed_mount:
         squashfs_cache_delete(msblk->block_cache);
         squashfs_cache_delete(msblk->fragment_cache);
         squashfs_cache_delete(msblk->read_page);
+        squashfs_zlib_free(msblk->stream);
         kfree(msblk->inode_lookup_table);
         kfree(msblk->fragment_index);
         kfree(msblk->id_table);
-        kfree(msblk->stream.workspace);
         kfree(sb->s_fs_info);
         sb->s_fs_info = NULL;
         kfree(sblk);
         return err;
 
 failure:
-        kfree(msblk->stream.workspace);
+        squashfs_zlib_free(msblk->stream);
         kfree(sb->s_fs_info);
         sb->s_fs_info = NULL;
         return -ENOMEM;
@@ -346,10 +342,10 @@ static void squashfs_put_super(struct super_block *sb)
                 squashfs_cache_delete(sbi->block_cache);
                 squashfs_cache_delete(sbi->fragment_cache);
                 squashfs_cache_delete(sbi->read_page);
+                squashfs_zlib_free(sbi->stream);
                 kfree(sbi->id_table);
                 kfree(sbi->fragment_index);
                 kfree(sbi->meta_index);
-                kfree(sbi->stream.workspace);
                 kfree(sb->s_fs_info);
                 sb->s_fs_info = NULL;
         }
diff --git a/fs/squashfs/symlink.c b/fs/squashfs/symlink.c
index 83d87880aac8..e80be2022a7f 100644
--- a/fs/squashfs/symlink.c
+++ b/fs/squashfs/symlink.c
@@ -36,7 +36,6 @@
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/pagemap.h>
-#include <linux/zlib.h>
 
 #include "squashfs_fs.h"
 #include "squashfs_fs_sb.h"
diff --git a/fs/squashfs/zlib_wrapper.c b/fs/squashfs/zlib_wrapper.c
index 3be99642d6af..c814594d522e 100644
--- a/fs/squashfs/zlib_wrapper.c
+++ b/fs/squashfs/zlib_wrapper.c
@@ -31,21 +31,51 @@
 #include "squashfs_fs_i.h"
 #include "squashfs.h"
 
+void *squashfs_zlib_init()
+{
+        z_stream *stream = kmalloc(sizeof(z_stream), GFP_KERNEL);
+        if (stream == NULL)
+                goto failed;
+        stream->workspace = kmalloc(zlib_inflate_workspacesize(),
+                GFP_KERNEL);
+        if (stream->workspace == NULL)
+                goto failed;
+
+        return stream;
+
+failed:
+        ERROR("Failed to allocate zlib workspace\n");
+        kfree(stream);
+        return NULL;
+}
+
+
+void squashfs_zlib_free(void *strm)
+{
+        z_stream *stream = strm;
+
+        if (stream)
+                kfree(stream->workspace);
+        kfree(stream);
+}
+
+
 int squashfs_zlib_uncompress(struct squashfs_sb_info *msblk, void **buffer,
         struct buffer_head **bh, int b, int offset, int length, int srclength,
         int pages)
 {
         int zlib_err = 0, zlib_init = 0;
         int avail, bytes, k = 0, page = 0;
+        z_stream *stream = msblk->stream;
 
         mutex_lock(&msblk->read_data_mutex);
 
-        msblk->stream.avail_out = 0;
-        msblk->stream.avail_in = 0;
+        stream->avail_out = 0;
+        stream->avail_in = 0;
 
         bytes = length;
         do {
-                if (msblk->stream.avail_in == 0 && k < b) {
+                if (stream->avail_in == 0 && k < b) {
                         avail = min(bytes, msblk->devblksize - offset);
                         bytes -= avail;
                         wait_on_buffer(bh[k]);
@@ -58,18 +88,18 @@ int squashfs_zlib_uncompress(struct squashfs_sb_info *msblk, void **buffer,
                                 continue;
                         }
 
-                        msblk->stream.next_in = bh[k]->b_data + offset;
-                        msblk->stream.avail_in = avail;
+                        stream->next_in = bh[k]->b_data + offset;
+                        stream->avail_in = avail;
                         offset = 0;
                 }
 
-                if (msblk->stream.avail_out == 0 && page < pages) {
-                        msblk->stream.next_out = buffer[page++];
-                        msblk->stream.avail_out = PAGE_CACHE_SIZE;
+                if (stream->avail_out == 0 && page < pages) {
+                        stream->next_out = buffer[page++];
+                        stream->avail_out = PAGE_CACHE_SIZE;
                 }
 
                 if (!zlib_init) {
-                        zlib_err = zlib_inflateInit(&msblk->stream);
+                        zlib_err = zlib_inflateInit(stream);
                         if (zlib_err != Z_OK) {
                                 ERROR("zlib_inflateInit returned unexpected "
                                         "result 0x%x, srclength %d\n",
@@ -79,9 +109,9 @@ int squashfs_zlib_uncompress(struct squashfs_sb_info *msblk, void **buffer,
                         zlib_init = 1;
                 }
 
-                zlib_err = zlib_inflate(&msblk->stream, Z_SYNC_FLUSH);
+                zlib_err = zlib_inflate(stream, Z_SYNC_FLUSH);
 
-                if (msblk->stream.avail_in == 0 && k < b)
+                if (stream->avail_in == 0 && k < b)
                         put_bh(bh[k++]);
         } while (zlib_err == Z_OK);
 
@@ -90,14 +120,14 @@ int squashfs_zlib_uncompress(struct squashfs_sb_info *msblk, void **buffer,
                 goto release_mutex;
         }
 
-        zlib_err = zlib_inflateEnd(&msblk->stream);
+        zlib_err = zlib_inflateEnd(stream);
         if (zlib_err != Z_OK) {
                 ERROR("zlib_inflate error, data probably corrupt\n");
                 goto release_mutex;
         }
 
         mutex_unlock(&msblk->read_data_mutex);
-        return msblk->stream.total_out;
+        return stream->total_out;
 
 release_mutex:
         mutex_unlock(&msblk->read_data_mutex);