Introduce a context structure for managing data blobs, and helper
functions for initializing and cleaning up this context structure.
Signed-off-by: Jeffle Xu <jefflexu@xxxxxxxxxxxxxxxxx>
---
fs/erofs/fscache.c | 46 +++++++++++++++++++++++++++++++++++++++++++++
fs/erofs/internal.h | 19 +++++++++++++++++++
2 files changed, 65 insertions(+)
diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c
index 7a6d0239ebb1..67a3c4935245 100644
--- a/fs/erofs/fscache.c
+++ b/fs/erofs/fscache.c
@@ -5,6 +5,52 @@
#include <linux/fscache.h>
#include "internal.h"
+/*
+ * Create an fscache context for data blob.
+ * Return: 0 on success and allocated fscache context is assigned to @fscache,
+ * negative error number on failure.
+ */
+int erofs_fscache_register_cookie(struct super_block *sb,
+ struct erofs_fscache **fscache, char *name)
+{
+ struct fscache_volume *volume = EROFS_SB(sb)->volume;
+ struct erofs_fscache *ctx;
+ struct fscache_cookie *cookie;
+
+ ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+
+ cookie = fscache_acquire_cookie(volume, FSCACHE_ADV_WANT_CACHE_SIZE,
+ name, strlen(name), NULL, 0, 0);
+ if (!cookie) {
+ erofs_err(sb, "failed to get cookie for %s", name);
+ kfree(name);
+ return -EINVAL;
+ }
+
+ fscache_use_cookie(cookie, false);
+ ctx->cookie = cookie;
+
+ *fscache = ctx;
+ return 0;
+}
+
+void erofs_fscache_unregister_cookie(struct erofs_fscache **fscache)
+{
+ struct erofs_fscache *ctx = *fscache;
+
+ if (!ctx)
+ return;
+
+ fscache_unuse_cookie(ctx->cookie, NULL, NULL);
+ fscache_relinquish_cookie(ctx->cookie, false);
+ ctx->cookie = NULL;
+
+ kfree(ctx);
+ *fscache = NULL;
+}
+
int erofs_fscache_register_fs(struct super_block *sb)
{
struct erofs_sb_info *sbi = EROFS_SB(sb);
diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index 952a2f483f94..c6a3351a4d7d 100644
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -97,6 +97,10 @@ struct erofs_sb_lz4_info {
u16 max_pclusterblks;
};
+struct erofs_fscache {
+ struct fscache_cookie *cookie;
+};
+
struct erofs_sb_info {
struct erofs_mount_opts opt; /* options */
#ifdef CONFIG_EROFS_FS_ZIP
@@ -626,9 +630,24 @@ static inline int z_erofs_load_lzma_config(struct super_block *sb,
#ifdef CONFIG_EROFS_FS_ONDEMAND
int erofs_fscache_register_fs(struct super_block *sb);
void erofs_fscache_unregister_fs(struct super_block *sb);
+
+int erofs_fscache_register_cookie(struct super_block *sb,
+ struct erofs_fscache **fscache, char *name);
+void erofs_fscache_unregister_cookie(struct erofs_fscache **fscache);
#else
static inline int erofs_fscache_register_fs(struct super_block *sb) { return 0; }
static inline void erofs_fscache_unregister_fs(struct super_block *sb) {}
+
+static inline int erofs_fscache_register_cookie(struct super_block *sb,
+ struct erofs_fscache **fscache,
+ char *name)
+{
+ return -EOPNOTSUPP;
+}
+
+static inline void erofs_fscache_unregister_cookie(struct erofs_fscache **fscache)
+{
+}
#endif
#define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */
--
2.27.0
--
Linux-cachefs mailing list
Linux-cachefs@xxxxxxxxxx
https://listman.redhat.com/mailman/listinfo/linux-cachefs
