vfs: track per-sb writeback errors and report them to syncfs

[linux-block.git] / include / linux / fs.h

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 45cc10cdf6ddd760aeadc92d255f65b132ed67cc..f2fb5b7406b9f4bbc324bffc22365261f1203c53 100644 (file)
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -976,6 +976,7 @@ struct file {
 #endif /* #ifdef CONFIG_EPOLL */
        struct address_space    *f_mapping;
        errseq_t                f_wb_err;
+       errseq_t                f_sb_err; /* for syncfs */
 } __randomize_layout
   __attribute__((aligned(4))); /* lest something weird decides that 2 is OK */
 
@@ -1520,6 +1521,9 @@ struct super_block {
        /* Being remounted read-only */
        int s_readonly_remount;
 
+       /* per-sb errseq_t for reporting writeback errors via syncfs */
+       errseq_t s_wb_err;
+
        /* AIO completions deferred from interrupt context */
        struct workqueue_struct *s_dio_done_wq;
        struct hlist_head s_pins;
@@ -2827,6 +2831,18 @@ static inline errseq_t filemap_sample_wb_err(struct address_space *mapping)
        return errseq_sample(&mapping->wb_err);
 }
 
+/**
+ * file_sample_sb_err - sample the current errseq_t to test for later errors
+ * @mapping: mapping to be sampled
+ *
+ * Grab the most current superblock-level errseq_t value for the given
+ * struct file.
+ */
+static inline errseq_t file_sample_sb_err(struct file *file)
+{
+       return errseq_sample(&file->f_path.dentry->d_sb->s_wb_err);
+}
+
 static inline int filemap_nr_thps(struct address_space *mapping)
 {
 #ifdef CONFIG_READ_ONLY_THP_FOR_FS