@@ -86,6 +86,70 @@ bool btrfs_compress_is_valid_type(const char *str, size_t len)
return false;
}
+static int compression_compress_pages(int type, struct list_head *ws,
+ struct address_space *mapping, u64 start, struct page **pages,
+ unsigned long *out_pages, unsigned long *total_in,
+ unsigned long *total_out)
+{
+ switch (type) {
+ case BTRFS_COMPRESS_ZLIB:
+ return zlib_compress_pages(ws, mapping, start, pages,
+ out_pages, total_in, total_out);
+ case BTRFS_COMPRESS_LZO:
+ return lzo_compress_pages(ws, mapping, start, pages,
+ out_pages, total_in, total_out);
+ case BTRFS_COMPRESS_ZSTD:
+ return zstd_compress_pages(ws, mapping, start, pages,
+ out_pages, total_in, total_out);
+ case BTRFS_COMPRESS_NONE:
+ default:
+ /*
+ * This can't happen, the type is validated several times
+ * before we get here. As a sane fallback, return what the
+ * callers will understand as 'no compression happened'.
+ */
+ return -E2BIG;
+ }
+}
+
+static int compression_decompress_bio(int type, struct list_head *ws,
+ struct compressed_bio *cb)
+{
+ switch (type) {
+ case BTRFS_COMPRESS_ZLIB: return zlib_decompress_bio(ws, cb);
+ case BTRFS_COMPRESS_LZO: return lzo_decompress_bio(ws, cb);
+ case BTRFS_COMPRESS_ZSTD: return zstd_decompress_bio(ws, cb);
+ case BTRFS_COMPRESS_NONE:
+ default:
+ /*
+ * This can't happen, the type is validated several times
+ * before we get here.
+ */
+ BUG();
+ }
+}
+
+static int compression_decompress(int type, struct list_head *ws,
+ unsigned char *data_in, struct page *dest_page,
+ unsigned long start_byte, size_t srclen, size_t destlen)
+{
+ switch (type) {
+ case BTRFS_COMPRESS_ZLIB: return zlib_decompress(ws, data_in, dest_page,
+ start_byte, srclen, destlen);
+ case BTRFS_COMPRESS_LZO: return lzo_decompress(ws, data_in, dest_page,
+ start_byte, srclen, destlen);
+ case BTRFS_COMPRESS_ZSTD: return zstd_decompress(ws, data_in, dest_page,
+ start_byte, srclen, destlen);
+ case BTRFS_COMPRESS_NONE:
+ default:
+ /*
+ * This can't happen, the type is validated several times
+ * before we get here.
+ */
+ BUG();
+ }
+}
+
static int btrfs_decompress_bio(struct compressed_bio *cb);
static inline int compressed_bio_size(struct btrfs_fs_info *fs_info,
@@ -1074,10 +1138,8 @@ int btrfs_compress_pages(unsigned int type_level, struct address_space *mapping,
level = btrfs_compress_set_level(type, level);
workspace = get_workspace(type, level);
- ret = btrfs_compress_op[type]->compress_pages(workspace, mapping,
- start, pages,
- out_pages,
- total_in, total_out);
+ ret = compression_compress_pages(type, workspace, mapping, start, pages,
+ out_pages, total_in, total_out);
put_workspace(type, workspace);
return ret;
}
@@ -1103,7 +1165,7 @@ static int btrfs_decompress_bio(struct compressed_bio *cb)
int type = cb->compress_type;
workspace = get_workspace(type, 0);
- ret = btrfs_compress_op[type]->decompress_bio(workspace, cb);
+ ret = compression_decompress_bio(type, workspace, cb);
put_workspace(type, workspace);
return ret;
@@ -1121,9 +1183,8 @@ int btrfs_decompress(int type, unsigned char *data_in, struct page *dest_page,
int ret;
workspace = get_workspace(type, 0);
- ret = btrfs_compress_op[type]->decompress(workspace, data_in,
- dest_page, start_byte,
- srclen, destlen);
+ ret = compression_decompress(type, workspace, data_in, dest_page,
+ start_byte, srclen, destlen);
put_workspace(type, workspace);
return ret;
@@ -140,23 +140,6 @@ struct btrfs_compress_op {
void (*free_workspace)(struct list_head *workspace);
- int (*compress_pages)(struct list_head *workspace,
- struct address_space *mapping,
- u64 start,
- struct page **pages,
- unsigned long *out_pages,
- unsigned long *total_in,
- unsigned long *total_out);
-
- int (*decompress_bio)(struct list_head *workspace,
- struct compressed_bio *cb);
-
- int (*decompress)(struct list_head *workspace,
- unsigned char *data_in,
- struct page *dest_page,
- unsigned long start_byte,
- size_t srclen, size_t destlen);
-
/* Maximum level supported by the compression algorithm */
unsigned int max_level;
unsigned int default_level;
@@ -509,9 +509,6 @@ const struct btrfs_compress_op btrfs_lzo_compress = {
.put_workspace = lzo_put_workspace,
.alloc_workspace = lzo_alloc_workspace,
.free_workspace = lzo_free_workspace,
- .compress_pages = lzo_compress_pages,
- .decompress_bio = lzo_decompress_bio,
- .decompress = lzo_decompress,
.max_level = 1,
.default_level = 1,
};
@@ -420,9 +420,6 @@ const struct btrfs_compress_op btrfs_zlib_compress = {
.put_workspace = zlib_put_workspace,
.alloc_workspace = zlib_alloc_workspace,
.free_workspace = zlib_free_workspace,
- .compress_pages = zlib_compress_pages,
- .decompress_bio = zlib_decompress_bio,
- .decompress = zlib_decompress,
.max_level = 9,
.default_level = BTRFS_ZLIB_DEFAULT_LEVEL,
};
@@ -713,9 +713,6 @@ const struct btrfs_compress_op btrfs_zstd_compress = {
.put_workspace = zstd_put_workspace,
.alloc_workspace = zstd_alloc_workspace,
.free_workspace = zstd_free_workspace,
- .compress_pages = zstd_compress_pages,
- .decompress_bio = zstd_decompress_bio,
- .decompress = zstd_decompress,
.max_level = ZSTD_BTRFS_MAX_LEVEL,
.default_level = ZSTD_BTRFS_DEFAULT_LEVEL,
};
The indirect calls bring some overhead due to spectre vulnerability mitigations. The number of cases is small and below the threshold (10-20) where indirect call would be better. Signed-off-by: David Sterba <dsterba@suse.com> --- fs/btrfs/compression.c | 77 +++++++++++++++++++++++++++++++++++++----- fs/btrfs/compression.h | 17 ---------- fs/btrfs/lzo.c | 3 -- fs/btrfs/zlib.c | 3 -- fs/btrfs/zstd.c | 3 -- 5 files changed, 69 insertions(+), 34 deletions(-)