Merge tag 'for-6.9-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

[linux-2.6-microblaze.git] / fs / btrfs / zstd.c

diff --git a/fs/btrfs/zstd.c b/fs/btrfs/zstd.c
index 0d66db8..92b3744 100644 (file)
--- a/fs/btrfs/zstd.c
+++ b/fs/btrfs/zstd.c
@@ -18,8 +18,9 @@
 #include <linux/slab.h>
 #include <linux/zstd.h>
 #include "misc.h"
+#include "fs.h"
 #include "compression.h"
-#include "ctree.h"
+#include "super.h"
 
 #define ZSTD_BTRFS_MAX_WINDOWLOG 17
 #define ZSTD_BTRFS_MAX_INPUT (1 << ZSTD_BTRFS_MAX_WINDOWLOG)
@@ -618,80 +619,48 @@ done:
 }
 
 int zstd_decompress(struct list_head *ws, const u8 *data_in,
-               struct page *dest_page, unsigned long start_byte, size_t srclen,
+               struct page *dest_page, unsigned long dest_pgoff, size_t srclen,
                size_t destlen)
 {
        struct workspace *workspace = list_entry(ws, struct workspace, list);
+       struct btrfs_fs_info *fs_info = btrfs_sb(dest_page->mapping->host->i_sb);
+       const u32 sectorsize = fs_info->sectorsize;
        zstd_dstream *stream;
        int ret = 0;
-       size_t ret2;
-       unsigned long total_out = 0;
-       unsigned long pg_offset = 0;
+       unsigned long to_copy = 0;
 
        stream = zstd_init_dstream(
                        ZSTD_BTRFS_MAX_INPUT, workspace->mem, workspace->size);
        if (!stream) {
                pr_warn("BTRFS: zstd_init_dstream failed\n");
-               ret = -EIO;
                goto finish;
        }
 
-       destlen = min_t(size_t, destlen, PAGE_SIZE);
-
        workspace->in_buf.src = data_in;
        workspace->in_buf.pos = 0;
        workspace->in_buf.size = srclen;
 
        workspace->out_buf.dst = workspace->buf;
        workspace->out_buf.pos = 0;
-       workspace->out_buf.size = PAGE_SIZE;
-
-       ret2 = 1;
-       while (pg_offset < destlen
-              && workspace->in_buf.pos < workspace->in_buf.size) {
-               unsigned long buf_start;
-               unsigned long buf_offset;
-               unsigned long bytes;
-
-               /* Check if the frame is over and we still need more input */
-               if (ret2 == 0) {
-                       pr_debug("BTRFS: zstd_decompress_stream ended early\n");
-                       ret = -EIO;
-                       goto finish;
-               }
-               ret2 = zstd_decompress_stream(stream, &workspace->out_buf,
-                               &workspace->in_buf);
-               if (zstd_is_error(ret2)) {
-                       pr_debug("BTRFS: zstd_decompress_stream returned %d\n",
-                                       zstd_get_error_code(ret2));
-                       ret = -EIO;
-                       goto finish;
-               }
-
-               buf_start = total_out;
-               total_out += workspace->out_buf.pos;
-               workspace->out_buf.pos = 0;
-
-               if (total_out <= start_byte)
-                       continue;
-
-               if (total_out > start_byte && buf_start < start_byte)
-                       buf_offset = start_byte - buf_start;
-               else
-                       buf_offset = 0;
-
-               bytes = min_t(unsigned long, destlen - pg_offset,
-                               workspace->out_buf.size - buf_offset);
-
-               memcpy_to_page(dest_page, pg_offset,
-                              workspace->out_buf.dst + buf_offset, bytes);
-
-               pg_offset += bytes;
+       workspace->out_buf.size = sectorsize;
+
+       /*
+        * Since both input and output buffers should not exceed one sector,
+        * one call should end the decompression.
+        */
+       ret = zstd_decompress_stream(stream, &workspace->out_buf, &workspace->in_buf);
+       if (zstd_is_error(ret)) {
+               pr_warn_ratelimited("BTRFS: zstd_decompress_stream return %d\n",
+                                   zstd_get_error_code(ret));
+               goto finish;
        }
-       ret = 0;
+       to_copy = workspace->out_buf.pos;
+       memcpy_to_page(dest_page, dest_pgoff, workspace->out_buf.dst, to_copy);
 finish:
-       if (pg_offset < destlen) {
-               memzero_page(dest_page, pg_offset, destlen - pg_offset);
+       /* Error or early end. */
+       if (unlikely(to_copy < destlen)) {
+               ret = -EIO;
+               memzero_page(dest_page, dest_pgoff + to_copy, destlen - to_copy);
        }
        return ret;
 }