2 files changed, 15 insertions, 59 deletions

diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 23efefa199..7adfbb04a7 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -6,6 +6,7 @@
  */
 
 #include "btrfs.h"
+#include <abuf.h>
 #include <log.h>
 #include <malloc.h>
 #include <linux/lzo.h>
@@ -136,54 +137,12 @@ static u32 decompress_zlib(const u8 *_cbuf, u32 clen, u8 *dbuf, u32 dlen)
 
 static u32 decompress_zstd(const u8 *cbuf, u32 clen, u8 *dbuf, u32 dlen)
 {
-	ZSTD_DStream *dstream;
-	ZSTD_inBuffer in_buf;
-	ZSTD_outBuffer out_buf;
-	void *workspace;
-	size_t wsize;
-	u32 res = -1;
-
-	wsize = ZSTD_DStreamWorkspaceBound(ZSTD_BTRFS_MAX_INPUT);
-	workspace = malloc(wsize);
-	if (!workspace) {
-		debug("%s: cannot allocate workspace of size %zu\n", __func__,
-		      wsize);
-		return -1;
-	}
-
-	dstream = ZSTD_initDStream(ZSTD_BTRFS_MAX_INPUT, workspace, wsize);
-	if (!dstream) {
-		printf("%s: ZSTD_initDStream failed\n", __func__);
-		goto err_free;
-	}
+	struct abuf in, out;
 
-	in_buf.src = cbuf;
-	in_buf.pos = 0;
-	in_buf.size = clen;
+	abuf_init_set(&in, (u8 *)cbuf, clen);
+	abuf_init_set(&out, dbuf, dlen);
 
-	out_buf.dst = dbuf;
-	out_buf.pos = 0;
-	out_buf.size = dlen;
-
-	while (1) {
-		size_t ret;
-
-		ret = ZSTD_decompressStream(dstream, &out_buf, &in_buf);
-		if (ZSTD_isError(ret)) {
-			printf("%s: ZSTD_decompressStream error %d\n", __func__,
-			       ZSTD_getErrorCode(ret));
-			goto err_free;
-		}
-
-		if (in_buf.pos >= clen || !ret)
-			break;
-	}
-
-	res = out_buf.pos;
-
-err_free:
-	free(workspace);
-	return res;
+	return zstd_decompress(&in, &out);
 }
 
 u32 btrfs_decompress(u8 type, const char *c, u32 clen, char *d, u32 dlen)
diff --git a/fs/fat/fat.c b/fs/fat/fat.c
index 7021138b98..65f77c4f75 100644
--- a/fs/fat/fat.c
+++ b/fs/fat/fat.c
@@ -275,22 +275,19 @@ get_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer, unsigned long size)
 			buffer += mydata->sect_size;
 			size -= mydata->sect_size;
 		}
-	} else {
-		__u32 idx;
-
-		idx = size / mydata->sect_size;
-		if (idx == 0)
-			ret = 0;
-		else
-			ret = disk_read(startsect, idx, buffer);
-		if (ret != idx) {
+	} else if (size >= mydata->sect_size) {
+		__u32 bytes_read;
+		__u32 sect_count = size / mydata->sect_size;
+
+		ret = disk_read(startsect, sect_count, buffer);
+		if (ret != sect_count) {
 			debug("Error reading data (got %d)\n", ret);
 			return -1;
 		}
-		startsect += idx;
-		idx *= mydata->sect_size;
-		buffer += idx;
-		size -= idx;
+		bytes_read = sect_count * mydata->sect_size;
+		startsect += sect_count;
+		buffer += bytes_read;
+		size -= bytes_read;
 	}
 	if (size) {
 		ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size);