btrfs: return errno instead of -1 from compression
The compression layer seems to have been built to return -1 and have
callers make up errors that make sense. This isn't great because there
are different errors that originate down in the compression layer.
Let's return real negative errnos from the compression layer so that
callers can pass on the error without having to guess what happened.
ENOMEM for allocation failure, E2BIG when compression exceeds the
uncompressed input, and EIO for everything else.
This helps a future path return errors from btrfs_decompress().
Signed-off-by: Zach Brown <zab@redhat.com>
Signed-off-by: Chris Mason <clm@fb.com>
diff --git a/fs/btrfs/zlib.c b/fs/btrfs/zlib.c
index 8e57191..4f19631 100644
--- a/fs/btrfs/zlib.c
+++ b/fs/btrfs/zlib.c
@@ -98,7 +98,7 @@
if (Z_OK != zlib_deflateInit(&workspace->def_strm, 3)) {
printk(KERN_WARNING "BTRFS: deflateInit failed\n");
- ret = -1;
+ ret = -EIO;
goto out;
}
@@ -110,7 +110,7 @@
out_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM);
if (out_page == NULL) {
- ret = -1;
+ ret = -ENOMEM;
goto out;
}
cpage_out = kmap(out_page);
@@ -128,7 +128,7 @@
printk(KERN_DEBUG "BTRFS: deflate in loop returned %d\n",
ret);
zlib_deflateEnd(&workspace->def_strm);
- ret = -1;
+ ret = -EIO;
goto out;
}
@@ -136,7 +136,7 @@
if (workspace->def_strm.total_in > 8192 &&
workspace->def_strm.total_in <
workspace->def_strm.total_out) {
- ret = -1;
+ ret = -EIO;
goto out;
}
/* we need another page for writing out. Test this
@@ -147,12 +147,12 @@
kunmap(out_page);
if (nr_pages == nr_dest_pages) {
out_page = NULL;
- ret = -1;
+ ret = -E2BIG;
goto out;
}
out_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM);
if (out_page == NULL) {
- ret = -1;
+ ret = -ENOMEM;
goto out;
}
cpage_out = kmap(out_page);
@@ -188,12 +188,12 @@
zlib_deflateEnd(&workspace->def_strm);
if (ret != Z_STREAM_END) {
- ret = -1;
+ ret = -EIO;
goto out;
}
if (workspace->def_strm.total_out >= workspace->def_strm.total_in) {
- ret = -1;
+ ret = -E2BIG;
goto out;
}
@@ -253,7 +253,7 @@
if (Z_OK != zlib_inflateInit2(&workspace->inf_strm, wbits)) {
printk(KERN_WARNING "BTRFS: inflateInit failed\n");
- return -1;
+ return -EIO;
}
while (workspace->inf_strm.total_in < srclen) {
ret = zlib_inflate(&workspace->inf_strm, Z_NO_FLUSH);
@@ -295,7 +295,7 @@
}
}
if (ret != Z_STREAM_END)
- ret = -1;
+ ret = -EIO;
else
ret = 0;
done:
@@ -337,7 +337,7 @@
if (Z_OK != zlib_inflateInit2(&workspace->inf_strm, wbits)) {
printk(KERN_WARNING "BTRFS: inflateInit failed\n");
- return -1;
+ return -EIO;
}
while (bytes_left > 0) {
@@ -354,7 +354,7 @@
total_out = workspace->inf_strm.total_out;
if (total_out == buf_start) {
- ret = -1;
+ ret = -EIO;
break;
}
@@ -382,7 +382,7 @@
}
if (ret != Z_STREAM_END && bytes_left != 0)
- ret = -1;
+ ret = -EIO;
else
ret = 0;
