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-rw-r--r--Documentation/filesystems/caching/backend-api.txt23
-rw-r--r--Documentation/filesystems/caching/fscache.txt7
-rw-r--r--Documentation/filesystems/dax.txt6
-rw-r--r--Documentation/filesystems/porting4
4 files changed, 37 insertions, 3 deletions
diff --git a/Documentation/filesystems/caching/backend-api.txt b/Documentation/filesystems/caching/backend-api.txt
index 277d1e810670..c0bd5677271b 100644
--- a/Documentation/filesystems/caching/backend-api.txt
+++ b/Documentation/filesystems/caching/backend-api.txt
@@ -676,6 +676,29 @@ FS-Cache provides some utilities that a cache backend may make use of:
as possible.
+ (*) Indicate that a stale object was found and discarded:
+
+ void fscache_object_retrying_stale(struct fscache_object *object);
+
+ This is called to indicate that the lookup procedure found an object in
+ the cache that the netfs decided was stale. The object has been
+ discarded from the cache and the lookup will be performed again.
+
+
+ (*) Indicate that the caching backend killed an object:
+
+ void fscache_object_mark_killed(struct fscache_object *object,
+ enum fscache_why_object_killed why);
+
+ This is called to indicate that the cache backend preemptively killed an
+ object. The why parameter should be set to indicate the reason:
+
+ FSCACHE_OBJECT_IS_STALE - the object was stale and needs discarding.
+ FSCACHE_OBJECT_NO_SPACE - there was insufficient cache space
+ FSCACHE_OBJECT_WAS_RETIRED - the object was retired when relinquished.
+ FSCACHE_OBJECT_WAS_CULLED - the object was culled to make space.
+
+
(*) Get and release references on a retrieval record:
void fscache_get_retrieval(struct fscache_retrieval *op);
diff --git a/Documentation/filesystems/caching/fscache.txt b/Documentation/filesystems/caching/fscache.txt
index 770267af5b3e..50f0a5757f48 100644
--- a/Documentation/filesystems/caching/fscache.txt
+++ b/Documentation/filesystems/caching/fscache.txt
@@ -284,8 +284,9 @@ proc files.
enq=N Number of times async ops queued for processing
can=N Number of async ops cancelled
rej=N Number of async ops rejected due to object lookup/create failure
+ ini=N Number of async ops initialised
dfr=N Number of async ops queued for deferred release
- rel=N Number of async ops released
+ rel=N Number of async ops released (should equal ini=N when idle)
gc=N Number of deferred-release async ops garbage collected
CacheOp alo=N Number of in-progress alloc_object() cache ops
luo=N Number of in-progress lookup_object() cache ops
@@ -303,6 +304,10 @@ proc files.
wrp=N Number of in-progress write_page() cache ops
ucp=N Number of in-progress uncache_page() cache ops
dsp=N Number of in-progress dissociate_pages() cache ops
+ CacheEv nsp=N Number of object lookups/creations rejected due to lack of space
+ stl=N Number of stale objects deleted
+ rtr=N Number of objects retired when relinquished
+ cul=N Number of objects culled
(*) /proc/fs/fscache/histogram
diff --git a/Documentation/filesystems/dax.txt b/Documentation/filesystems/dax.txt
index baf41118660d..7af2851d667c 100644
--- a/Documentation/filesystems/dax.txt
+++ b/Documentation/filesystems/dax.txt
@@ -18,8 +18,10 @@ Usage
-----
If you have a block device which supports DAX, you can make a filesystem
-on it as usual. When mounting it, use the -o dax option manually
-or add 'dax' to the options in /etc/fstab.
+on it as usual. The DAX code currently only supports files with a block
+size equal to your kernel's PAGE_SIZE, so you may need to specify a block
+size when creating the filesystem. When mounting it, use the "-o dax"
+option on the command line or add 'dax' to the options in /etc/fstab.
Implementation Tips for Block Driver Writers
diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting
index 68f1c9106573..f24d1b833957 100644
--- a/Documentation/filesystems/porting
+++ b/Documentation/filesystems/porting
@@ -500,3 +500,7 @@ in your dentry operations instead.
dentry, it does not get nameidata at all and it gets called only when cookie
is non-NULL. Note that link body isn't available anymore, so if you need it,
store it as cookie.
+--
+[mandatory]
+ __fd_install() & fd_install() can now sleep. Callers should not
+ hold a spinlock or other resources that do not allow a schedule.