path: root/Documentation
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authorLinus Torvalds <torvalds@linux-foundation.org>2015-07-04 19:36:06 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-07-04 19:36:06 -0700
commit1dc51b8288007753ad7cd7d08bb8fa930fc8bb10 (patch)
tree0616c0ff7d877e64d9c248a6cdff074eae258840 /Documentation
parent9b284cbdb5de3b8871014f8290d1b540e5181c21 (diff)
parent0f1db7dee200127da4c07928189748918c312031 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more vfs updates from Al Viro: "Assorted VFS fixes and related cleanups (IMO the most interesting in that part are f_path-related things and Eric's descriptor-related stuff). UFS regression fixes (it got broken last cycle). 9P fixes. fs-cache series, DAX patches, Jan's file_remove_suid() work" [ I'd say this is much more than "fixes and related cleanups". The file_table locking rule change by Eric Dumazet is a rather big and fundamental update even if the patch isn't huge. - Linus ] * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits) 9p: cope with bogus responses from server in p9_client_{read,write} p9_client_write(): avoid double p9_free_req() 9p: forgetting to cancel request on interrupted zero-copy RPC dax: bdev_direct_access() may sleep block: Add support for DAX reads/writes to block devices dax: Use copy_from_iter_nocache dax: Add block size note to documentation fs/file.c: __fget() and dup2() atomicity rules fs/file.c: don't acquire files->file_lock in fd_install() fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation vfs: avoid creation of inode number 0 in get_next_ino namei: make set_root_rcu() return void make simple_positive() public ufs: use dir_pages instead of ufs_dir_pages() pagemap.h: move dir_pages() over there remove the pointless include of lglock.h fs: cleanup slight list_entry abuse xfs: Correctly lock inode when removing suid and file capabilities fs: Call security_ops->inode_killpriv on truncate fs: Provide function telling whether file_remove_privs() will do anything ...
Diffstat (limited to 'Documentation')
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.
+ __fd_install() & fd_install() can now sleep. Callers should not
+ hold a spinlock or other resources that do not allow a schedule.