cachefiles: Add cache error reporting macro

Add a macro to report a cache I/O error and to tell fscache that the cache
is in trouble.

Also add a pointer to the fscache cache cookie from the cachefiles_cache
struct as we need that to pass to fscache_io_error().

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819626562.215744.1503690975344731661.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906927235.143852.13694625647880837563.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967137158.1823006.2065038830569321335.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021536053.640689.5306822604644352548.stgit@warthog.procyon.org.uk/

diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h
index b51146a..b2adcb5 100644 (file)
--- a/fs/cachefiles/internal.h
+++ b/fs/cachefiles/internal.h
@@ -30,6 +30,7 @@ struct cachefiles_object {
  * Cache files cache definition
  */
 struct cachefiles_cache {
+       struct fscache_cache            *cache;         /* Cache cookie */
        struct vfsmount                 *mnt;           /* mountpoint holding the cache */
        struct file                     *cachefilesd;   /* manager daemon handle */
        const struct cred               *cache_cred;    /* security override for accessing cache */
@@ -103,6 +104,16 @@ static inline int cachefiles_inject_remove_error(void)
        return cachefiles_error_injection_state & 2 ? -EIO : 0;
 }
 
+/*
+ * Error handling
+ */
+#define cachefiles_io_error(___cache, FMT, ...)                \
+do {                                                   \
+       pr_err("I/O Error: " FMT"\n", ##__VA_ARGS__);   \
+       fscache_io_error((___cache)->cache);            \
+       set_bit(CACHEFILES_DEAD, &(___cache)->flags);   \
+} while (0)
+
 
 /*
  * Debug tracing