diff mbox series

[v3,2/4] fs/squashfs: add support for ZSTD decompression

Message ID 20200818143118.16422-3-joaomarcos.costa@bootlin.com
State Superseded
Delegated to: Tom Rini
Headers show
Series fs/squashfs: Add new decompression algorithms | expand

Commit Message

Joao Marcos Costa Aug. 18, 2020, 2:31 p.m. UTC 
Add call to ZSTD's ZSTD_decompressDCtx(). In this use case, the caller
can upper bound the decompressed size, which will be the SquashFS data
block (or metadata block) size, so there is no need to use streaming
API. Add ZSTD's worskpace to squashfs_ctxt structure.

Signed-off-by: Joao Marcos Costa <joaomarcos.costa@bootlin.com>
---
Changes in v3:
	- Remove memory leak from sqfs_zstd_decompress()
Changes in v2:
	- No changes since last version.
 fs/squashfs/sqfs_decompressor.c | 42 +++++++++++++++++++++++++++++++++
 fs/squashfs/sqfs_filesystem.h   |  3 +++
 2 files changed, 45 insertions(+)

Comments

Thomas Petazzoni Aug. 18, 2020, 2:35 p.m. UTC | #1 
Hello,

On Tue, 18 Aug 2020 16:31:16 +0200
Joao Marcos Costa <joaomarcos.costa@bootlin.com> wrote:

> +#if IS_ENABLED(CONFIG_ZSTD)
> +static int sqfs_zstd_decompress(void *dest, unsigned long dest_len,
> +				void *source, u32 src_len)

Pass the squashfs_context structure as argument to the decompressor
function, so that sqfs_ctxt doesn't need to be a global variable.

Best regards,

Thomas
Joao Marcos Costa Aug. 18, 2020, 3:16 p.m. UTC | #2 
On Tue, 18 Aug 2020 16:35:27 +0200
Thomas Petazzoni <thomas.petazzoni@bootlin.com> wrote:

> Hello,
> 
> On Tue, 18 Aug 2020 16:31:16 +0200
> Joao Marcos Costa <joaomarcos.costa@bootlin.com> wrote:
> 
> > +#if IS_ENABLED(CONFIG_ZSTD)
> > +static int sqfs_zstd_decompress(void *dest, unsigned long dest_len,
> > +				void *source, u32 src_len)  
> 
> Pass the squashfs_context structure as argument to the decompressor
> function, so that sqfs_ctxt doesn't need to be a global variable.
> 
> Best regards,
> 
> Thomas

Thanks for the remarks, I am preparing a v4 and I will send it in a
few minutes.

Best regards,
Joao
diff mbox series

Patch

diff --git a/fs/squashfs/sqfs_decompressor.c b/fs/squashfs/sqfs_decompressor.c
index 577cffd8bb..8fdaaa853c 100644
--- a/fs/squashfs/sqfs_decompressor.c
+++ b/fs/squashfs/sqfs_decompressor.c
@@ -13,6 +13,10 @@ 
 #include <u-boot/zlib.h>
 #endif
 
+#if IS_ENABLED(CONFIG_ZSTD)
+#include <linux/zstd.h>
+#endif
+
 #include "sqfs_decompressor.h"
 #include "sqfs_utils.h"
 
@@ -26,6 +30,13 @@  int sqfs_decompressor_init(struct squashfs_ctxt *ctxt)
 #if IS_ENABLED(CONFIG_ZLIB)
 	case SQFS_COMP_ZLIB:
 		break;
+#endif
+#if IS_ENABLED(CONFIG_ZSTD)
+	case SQFS_COMP_ZSTD:
+		ctxt->zstd_workspace = malloc(ZSTD_DCtxWorkspaceBound());
+		if (!ctxt->zstd_workspace)
+			return -ENOMEM;
+		break;
 #endif
 	default:
 		printf("Error: unknown compression type.\n");
@@ -43,6 +54,11 @@  void sqfs_decompressor_cleanup(struct squashfs_ctxt *ctxt)
 #if IS_ENABLED(CONFIG_ZLIB)
 	case SQFS_COMP_ZLIB:
 		break;
+#endif
+#if IS_ENABLED(CONFIG_ZSTD)
+	case SQFS_COMP_ZSTD:
+		free(ctxt->zstd_workspace);
+		break;
 #endif
 	}
 }
@@ -64,6 +80,22 @@  static void zlib_decompression_status(int ret)
 }
 #endif
 
+#if IS_ENABLED(CONFIG_ZSTD)
+static int sqfs_zstd_decompress(void *dest, unsigned long dest_len,
+				void *source, u32 src_len)
+{
+	ZSTD_DCtx *ctx;
+	size_t wsize;
+	int ret;
+
+	wsize = ZSTD_DCtxWorkspaceBound();
+	ctx = ZSTD_initDCtx(sqfs_ctxt.zstd_workspace, wsize);
+	ret = ZSTD_decompressDCtx(ctx, dest, dest_len, source, src_len);
+
+	return ZSTD_isError(ret);
+}
+#endif /* CONFIG_ZSTD */
+
 int sqfs_decompress(u16 comp_type, void *dest, unsigned long *dest_len,
 		    void *source, u32 src_len)
 {
@@ -80,6 +112,16 @@  int sqfs_decompress(u16 comp_type, void *dest, unsigned long *dest_len,
 
 		break;
 #endif
+#if IS_ENABLED(CONFIG_ZSTD)
+	case SQFS_COMP_ZSTD:
+		ret = sqfs_zstd_decompress(dest, *dest_len, source, src_len);
+		if (ret) {
+			printf("ZSTD Error code: %d\n", ZSTD_getErrorCode(ret));
+			return -EINVAL;
+		}
+
+		break;
+#endif
 	default:
 		printf("Error: unknown compression type.\n");
 		return -EINVAL;
diff --git a/fs/squashfs/sqfs_filesystem.h b/fs/squashfs/sqfs_filesystem.h
index ff2b0b1d34..856cd15e34 100644
--- a/fs/squashfs/sqfs_filesystem.h
+++ b/fs/squashfs/sqfs_filesystem.h
@@ -77,6 +77,9 @@  struct squashfs_ctxt {
 	struct disk_partition cur_part_info;
 	struct blk_desc *cur_dev;
 	struct squashfs_super_block *sblk;
+#if IS_ENABLED(CONFIG_ZSTD)
+	void *zstd_workspace;
+#endif
 };
 
 struct squashfs_directory_index {