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-rw-r--r--Documentation/filesystems/dax.txt1
-rw-r--r--Documentation/filesystems/ext2.txt2
-rw-r--r--Documentation/filesystems/ext4.txt9
-rw-r--r--Documentation/filesystems/fscrypt.rst10
-rw-r--r--Documentation/filesystems/nfs/Exporting27
-rw-r--r--Documentation/filesystems/sysfs.txt4
-rw-r--r--Documentation/filesystems/vfat.txt2
7 files changed, 34 insertions, 21 deletions
diff --git a/Documentation/filesystems/dax.txt b/Documentation/filesystems/dax.txt
index 3be3b26..70cb68b 100644
--- a/Documentation/filesystems/dax.txt
+++ b/Documentation/filesystems/dax.txt
@@ -46,7 +46,6 @@ stall the CPU for an extended period, you should also not attempt to
implement direct_access.
These block devices may be used for inspiration:
-- axonram: Axon DDR2 device driver
- brd: RAM backed block device driver
- dcssblk: s390 dcss block device driver
- pmem: NVDIMM persistent memory driver
diff --git a/Documentation/filesystems/ext2.txt b/Documentation/filesystems/ext2.txt
index 5575539..81c0bec 100644
--- a/Documentation/filesystems/ext2.txt
+++ b/Documentation/filesystems/ext2.txt
@@ -49,12 +49,10 @@ sb=n Use alternate superblock at this location.
user_xattr Enable "user." POSIX Extended Attributes
(requires CONFIG_EXT2_FS_XATTR).
- See also http://acl.bestbits.at
nouser_xattr Don't support "user." extended attributes.
acl Enable POSIX Access Control Lists support
(requires CONFIG_EXT2_FS_POSIX_ACL).
- See also http://acl.bestbits.at
noacl Don't support POSIX ACLs.
nobh Do not attach buffer_heads to file pagecache.
diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt
index 75236c0..7f628b9 100644
--- a/Documentation/filesystems/ext4.txt
+++ b/Documentation/filesystems/ext4.txt
@@ -202,15 +202,14 @@ inode_readahead_blks=n This tuning parameter controls the maximum
the buffer cache. The default value is 32 blocks.
nouser_xattr Disables Extended User Attributes. See the
- attr(5) manual page and http://acl.bestbits.at/
- for more information about extended attributes.
+ attr(5) manual page for more information about
+ extended attributes.
noacl This option disables POSIX Access Control List
support. If ACL support is enabled in the kernel
configuration (CONFIG_EXT4_FS_POSIX_ACL), ACL is
enabled by default on mount. See the acl(5) manual
- page and http://acl.bestbits.at/ for more information
- about acl.
+ page for more information about acl.
bsddf (*) Make 'df' act like BSD.
minixdf Make 'df' act like Minix.
@@ -233,7 +232,7 @@ data_err=ignore(*) Just print an error message if an error occurs
data_err=abort Abort the journal if an error occurs in a file
data buffer in ordered mode.
-grpid Give objects the same group ID as their creator.
+grpid New objects have the group ID of their parent.
bsdgroups
nogrpid (*) New objects have the group ID of their creator.
diff --git a/Documentation/filesystems/fscrypt.rst b/Documentation/filesystems/fscrypt.rst
index 776ddc6..cfbc18f 100644
--- a/Documentation/filesystems/fscrypt.rst
+++ b/Documentation/filesystems/fscrypt.rst
@@ -448,8 +448,14 @@ astute users may notice some differences in behavior:
- The st_size of an encrypted symlink will not necessarily give the
length of the symlink target as required by POSIX. It will actually
- give the length of the ciphertext, which may be slightly longer than
- the plaintext due to the NUL-padding.
+ give the length of the ciphertext, which will be slightly longer
+ than the plaintext due to NUL-padding and an extra 2-byte overhead.
+
+- The maximum length of an encrypted symlink is 2 bytes shorter than
+ the maximum length of an unencrypted symlink. For example, on an
+ EXT4 filesystem with a 4K block size, unencrypted symlinks can be up
+ to 4095 bytes long, while encrypted symlinks can only be up to 4093
+ bytes long (both lengths excluding the terminating null).
Note that mmap *is* supported. This is possible because the pagecache
for an encrypted file contains the plaintext, not the ciphertext.
diff --git a/Documentation/filesystems/nfs/Exporting b/Documentation/filesystems/nfs/Exporting
index 520a4be..6388914 100644
--- a/Documentation/filesystems/nfs/Exporting
+++ b/Documentation/filesystems/nfs/Exporting
@@ -56,13 +56,25 @@ a/ A dentry flag DCACHE_DISCONNECTED which is set on
any dentry that might not be part of the proper prefix.
This is set when anonymous dentries are created, and cleared when a
dentry is noticed to be a child of a dentry which is in the proper
- prefix.
-
-b/ A per-superblock list "s_anon" of dentries which are the roots of
- subtrees that are not in the proper prefix. These dentries, as
- well as the proper prefix, need to be released at unmount time. As
- these dentries will not be hashed, they are linked together on the
- d_hash list_head.
+ prefix. If the refcount on a dentry with this flag set
+ becomes zero, the dentry is immediately discarded, rather than being
+ kept in the dcache. If a dentry that is not already in the dcache
+ is repeatedly accessed by filehandle (as NFSD might do), an new dentry
+ will be a allocated for each access, and discarded at the end of
+ the access.
+
+ Note that such a dentry can acquire children, name, ancestors, etc.
+ without losing DCACHE_DISCONNECTED - that flag is only cleared when
+ subtree is successfully reconnected to root. Until then dentries
+ in such subtree are retained only as long as there are references;
+ refcount reaching zero means immediate eviction, same as for unhashed
+ dentries. That guarantees that we won't need to hunt them down upon
+ umount.
+
+b/ A primitive for creation of secondary roots - d_obtain_root(inode).
+ Those do _not_ bear DCACHE_DISCONNECTED. They are placed on the
+ per-superblock list (->s_roots), so they can be located at umount
+ time for eviction purposes.
c/ Helper routines to allocate anonymous dentries, and to help attach
loose directory dentries at lookup time. They are:
@@ -77,7 +89,6 @@ c/ Helper routines to allocate anonymous dentries, and to help attach
(such as an anonymous one created by d_obtain_alias), if appropriate.
It returns NULL when the passed-in dentry is used, following the calling
convention of ->lookup.
-
Filesystem Issues
-----------------
diff --git a/Documentation/filesystems/sysfs.txt b/Documentation/filesystems/sysfs.txt
index 9a3658c..a1426ca 100644
--- a/Documentation/filesystems/sysfs.txt
+++ b/Documentation/filesystems/sysfs.txt
@@ -154,8 +154,8 @@ static ssize_t dev_attr_show(struct kobject *kobj, struct attribute *attr,
if (dev_attr->show)
ret = dev_attr->show(dev, dev_attr, buf);
if (ret >= (ssize_t)PAGE_SIZE) {
- print_symbol("dev_attr_show: %s returned bad count\n",
- (unsigned long)dev_attr->show);
+ printk("dev_attr_show: %pS returned bad count\n",
+ dev_attr->show);
}
return ret;
}
diff --git a/Documentation/filesystems/vfat.txt b/Documentation/filesystems/vfat.txt
index cf51360..9103129 100644
--- a/Documentation/filesystems/vfat.txt
+++ b/Documentation/filesystems/vfat.txt
@@ -344,4 +344,4 @@ the following:
characters in the final slot are set to Unicode 0xFFFF.
Finally, note that the extended name is stored in Unicode. Each Unicode
-character takes two bytes.
+character takes either two or four bytes, UTF-16LE encoded.
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