logfs: handle powerfail on NAND flash

[sfrench/cifs-2.6.git] / fs / logfs / logfs.h

diff --git a/fs/logfs/logfs.h b/fs/logfs/logfs.h
index 0a3df1a0c93687932b729174c10a4960ec48265b..93b55f3372451b00fd03bad81424808ede0b1825 100644 (file)
--- a/fs/logfs/logfs.h
+++ b/fs/logfs/logfs.h
@@ -144,6 +144,7 @@ struct logfs_area_ops {
  * @erase:                     erase one segment
  * @read:                      read from the device
  * @erase:                     erase part of the device
+ * @can_write_buf:             decide whether wbuf can be written to ofs
  */
 struct logfs_device_ops {
        struct page *(*find_first_sb)(struct super_block *sb, u64 *ofs);
@@ -153,6 +154,7 @@ struct logfs_device_ops {
        void (*writeseg)(struct super_block *sb, u64 ofs, size_t len);
        int (*erase)(struct super_block *sb, loff_t ofs, size_t len,
                        int ensure_write);
+       int (*can_write_buf)(struct super_block *sb, u64 ofs);
        void (*sync)(struct super_block *sb);
        void (*put_device)(struct super_block *sb);
 };
@@ -394,6 +396,7 @@ struct logfs_super {
        int      s_lock_count;
        mempool_t *s_block_pool;                /* struct logfs_block pool */
        mempool_t *s_shadow_pool;               /* struct logfs_shadow pool */
+       struct list_head s_writeback_list;      /* writeback pages */
        /*
         * Space accounting:
         * - s_used_bytes specifies space used to store valid data objects.
@@ -598,19 +601,19 @@ void freeseg(struct super_block *sb, u32 segno);
 int logfs_init_areas(struct super_block *sb);
 void logfs_cleanup_areas(struct super_block *sb);
 int logfs_open_area(struct logfs_area *area, size_t bytes);
-void __logfs_buf_write(struct logfs_area *area, u64 ofs, void *buf, size_t len,
+int __logfs_buf_write(struct logfs_area *area, u64 ofs, void *buf, size_t len,
                int use_filler);
 
-static inline void logfs_buf_write(struct logfs_area *area, u64 ofs,
+static inline int logfs_buf_write(struct logfs_area *area, u64 ofs,
                void *buf, size_t len)
 {
-       __logfs_buf_write(area, ofs, buf, len, 0);
+       return __logfs_buf_write(area, ofs, buf, len, 0);
 }
 
-static inline void logfs_buf_recover(struct logfs_area *area, u64 ofs,
+static inline int logfs_buf_recover(struct logfs_area *area, u64 ofs,
                void *buf, size_t len)
 {
-       __logfs_buf_write(area, ofs, buf, len, 1);
+       return __logfs_buf_write(area, ofs, buf, len, 1);
 }
 
 /* super.c */