<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/fs/namei.c, branch v5.3.2</title>
<subtitle>Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git</subtitle>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/'/>
<entry>
<title>fsnotify: add empty fsnotify_{unlink,rmdir}() hooks</title>
<updated>2019-06-20T12:44:55+00:00</updated>
<author>
<name>Amir Goldstein</name>
<email>amir73il@gmail.com</email>
</author>
<published>2019-05-26T14:34:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=116b9731ad7614032a390bb9ad8998a14d6dc752'/>
<id>116b9731ad7614032a390bb9ad8998a14d6dc752</id>
<content type='text'>
We would like to move fsnotify_nameremove() calls from d_delete()
into a higher layer where the hook makes more sense and so we can
consider every d_delete() call site individually.

Start by creating empty hook fsnotify_{unlink,rmdir}() and place
them in the proper VFS call sites.  After all d_delete() call sites
will be converted to use the new hook, the new hook will generate the
delete events and fsnotify_nameremove() hook will be removed.

Signed-off-by: Amir Goldstein &lt;amir73il@gmail.com&gt;
Signed-off-by: Jan Kara &lt;jack@suse.cz&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We would like to move fsnotify_nameremove() calls from d_delete()
into a higher layer where the hook makes more sense and so we can
consider every d_delete() call site individually.

Start by creating empty hook fsnotify_{unlink,rmdir}() and place
them in the proper VFS call sites.  After all d_delete() call sites
will be converted to use the new hook, the new hook will generate the
delete events and fsnotify_nameremove() hook will be removed.

Signed-off-by: Amir Goldstein &lt;amir73il@gmail.com&gt;
Signed-off-by: Jan Kara &lt;jack@suse.cz&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt</title>
<updated>2019-05-08T04:28:04+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-05-08T04:28:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=a9fbcd6728837268784439ad0b02ede2c024c516'/>
<id>a9fbcd6728837268784439ad0b02ede2c024c516</id>
<content type='text'>
Pull fscrypt updates from Ted Ts'o:
 "Clean up fscrypt's dcache revalidation support, and other
  miscellaneous cleanups"

* tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt:
  fscrypt: cache decrypted symlink target in -&gt;i_link
  vfs: use READ_ONCE() to access -&gt;i_link
  fscrypt: fix race where -&gt;lookup() marks plaintext dentry as ciphertext
  fscrypt: only set dentry_operations on ciphertext dentries
  fs, fscrypt: clear DCACHE_ENCRYPTED_NAME when unaliasing directory
  fscrypt: fix race allowing rename() and link() of ciphertext dentries
  fscrypt: clean up and improve dentry revalidation
  fscrypt: use READ_ONCE() to access -&gt;i_crypt_info
  fscrypt: remove WARN_ON_ONCE() when decryption fails
  fscrypt: drop inode argument from fscrypt_get_ctx()
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull fscrypt updates from Ted Ts'o:
 "Clean up fscrypt's dcache revalidation support, and other
  miscellaneous cleanups"

* tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt:
  fscrypt: cache decrypted symlink target in -&gt;i_link
  vfs: use READ_ONCE() to access -&gt;i_link
  fscrypt: fix race where -&gt;lookup() marks plaintext dentry as ciphertext
  fscrypt: only set dentry_operations on ciphertext dentries
  fs, fscrypt: clear DCACHE_ENCRYPTED_NAME when unaliasing directory
  fscrypt: fix race allowing rename() and link() of ciphertext dentries
  fscrypt: clean up and improve dentry revalidation
  fscrypt: use READ_ONCE() to access -&gt;i_crypt_info
  fscrypt: remove WARN_ON_ONCE() when decryption fails
  fscrypt: drop inode argument from fscrypt_get_ctx()
</pre>
</div>
</content>
</entry>
<entry>
<title>switch fsnotify_move() to passing const struct qstr * for old_name</title>
<updated>2019-04-26T17:22:05+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2019-04-26T17:21:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=f4ec3a3d43bcdcf6295af9f3715a5a33f59bb6ce'/>
<id>f4ec3a3d43bcdcf6295af9f3715a5a33f59bb6ce</id>
<content type='text'>
note that in the second (RENAME_EXCHANGE) call of fsnotify_move() in
vfs_rename() the old_dentry-&gt;d_name is guaranteed to be unchanged
throughout the evaluation of fsnotify_move() (by the fact that the
parent directory is locked exclusive), so we don't need to fetch
old_dentry-&gt;d_name.name in the caller.

Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
note that in the second (RENAME_EXCHANGE) call of fsnotify_move() in
vfs_rename() the old_dentry-&gt;d_name is guaranteed to be unchanged
throughout the evaluation of fsnotify_move() (by the fact that the
parent directory is locked exclusive), so we don't need to fetch
old_dentry-&gt;d_name.name in the caller.

Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ovl_lookup_real_one(): don't bother with strlen()</title>
<updated>2019-04-26T17:13:33+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2019-04-26T17:07:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=230c6402b1b305c21c91b56cd9de95a608898506'/>
<id>230c6402b1b305c21c91b56cd9de95a608898506</id>
<content type='text'>
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>vfs: use READ_ONCE() to access -&gt;i_link</title>
<updated>2019-04-17T16:43:14+00:00</updated>
<author>
<name>Eric Biggers</name>
<email>ebiggers@google.com</email>
</author>
<published>2019-04-10T20:21:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=4c4f7c19b3c721aed418bc97907b411608c5c6a0'/>
<id>4c4f7c19b3c721aed418bc97907b411608c5c6a0</id>
<content type='text'>
Use 'READ_ONCE(inode-&gt;i_link)' to explicitly support filesystems caching
the symlink target in -&gt;i_link later if it was unavailable at iget()
time, or wasn't easily available.  I'll be doing this in fscrypt, to
improve the performance of encrypted symlinks on ext4, f2fs, and ubifs.

-&gt;i_link will start NULL and may later be set to a non-NULL value by a
smp_store_release() or cmpxchg_release().  READ_ONCE() is needed on the
read side.  smp_load_acquire() is unnecessary because only a data
dependency barrier is required.  (Thanks to Al for pointing this out.)

Acked-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Signed-off-by: Theodore Ts'o &lt;tytso@mit.edu&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Use 'READ_ONCE(inode-&gt;i_link)' to explicitly support filesystems caching
the symlink target in -&gt;i_link later if it was unavailable at iget()
time, or wasn't easily available.  I'll be doing this in fscrypt, to
improve the performance of encrypted symlinks on ext4, f2fs, and ubifs.

-&gt;i_link will start NULL and may later be set to a non-NULL value by a
smp_store_release() or cmpxchg_release().  READ_ONCE() is needed on the
read side.  smp_load_acquire() is unnecessary because only a data
dependency barrier is required.  (Thanks to Al for pointing this out.)

Acked-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Signed-off-by: Theodore Ts'o &lt;tytso@mit.edu&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs</title>
<updated>2019-03-12T21:08:19+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-03-12T21:08:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=7b47a9e7c8f672b6fb0b77fca11a63a8a77f5a91'/>
<id>7b47a9e7c8f672b6fb0b77fca11a63a8a77f5a91</id>
<content type='text'>
Pull vfs mount infrastructure updates from Al Viro:
 "The rest of core infrastructure; no new syscalls in that pile, but the
  old parts are switched to new infrastructure. At that point
  conversions of individual filesystems can happen independently; some
  are done here (afs, cgroup, procfs, etc.), there's also a large series
  outside of that pile dealing with NFS (quite a bit of option-parsing
  stuff is getting used there - it's one of the most convoluted
  filesystems in terms of mount-related logics), but NFS bits are the
  next cycle fodder.

  It got seriously simplified since the last cycle; documentation is
  probably the weakest bit at the moment - I considered dropping the
  commit introducing Documentation/filesystems/mount_api.txt (cutting
  the size increase by quarter ;-), but decided that it would be better
  to fix it up after -rc1 instead.

  That pile allows to do followup work in independent branches, which
  should make life much easier for the next cycle. fs/super.c size
  increase is unpleasant; there's a followup series that allows to
  shrink it considerably, but I decided to leave that until the next
  cycle"

* 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (41 commits)
  afs: Use fs_context to pass parameters over automount
  afs: Add fs_context support
  vfs: Add some logging to the core users of the fs_context log
  vfs: Implement logging through fs_context
  vfs: Provide documentation for new mount API
  vfs: Remove kern_mount_data()
  hugetlbfs: Convert to fs_context
  cpuset: Use fs_context
  kernfs, sysfs, cgroup, intel_rdt: Support fs_context
  cgroup: store a reference to cgroup_ns into cgroup_fs_context
  cgroup1_get_tree(): separate "get cgroup_root to use" into a separate helper
  cgroup_do_mount(): massage calling conventions
  cgroup: stash cgroup_root reference into cgroup_fs_context
  cgroup2: switch to option-by-option parsing
  cgroup1: switch to option-by-option parsing
  cgroup: take options parsing into -&gt;parse_monolithic()
  cgroup: fold cgroup1_mount() into cgroup1_get_tree()
  cgroup: start switching to fs_context
  ipc: Convert mqueue fs to fs_context
  proc: Add fs_context support to procfs
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull vfs mount infrastructure updates from Al Viro:
 "The rest of core infrastructure; no new syscalls in that pile, but the
  old parts are switched to new infrastructure. At that point
  conversions of individual filesystems can happen independently; some
  are done here (afs, cgroup, procfs, etc.), there's also a large series
  outside of that pile dealing with NFS (quite a bit of option-parsing
  stuff is getting used there - it's one of the most convoluted
  filesystems in terms of mount-related logics), but NFS bits are the
  next cycle fodder.

  It got seriously simplified since the last cycle; documentation is
  probably the weakest bit at the moment - I considered dropping the
  commit introducing Documentation/filesystems/mount_api.txt (cutting
  the size increase by quarter ;-), but decided that it would be better
  to fix it up after -rc1 instead.

  That pile allows to do followup work in independent branches, which
  should make life much easier for the next cycle. fs/super.c size
  increase is unpleasant; there's a followup series that allows to
  shrink it considerably, but I decided to leave that until the next
  cycle"

* 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (41 commits)
  afs: Use fs_context to pass parameters over automount
  afs: Add fs_context support
  vfs: Add some logging to the core users of the fs_context log
  vfs: Implement logging through fs_context
  vfs: Provide documentation for new mount API
  vfs: Remove kern_mount_data()
  hugetlbfs: Convert to fs_context
  cpuset: Use fs_context
  kernfs, sysfs, cgroup, intel_rdt: Support fs_context
  cgroup: store a reference to cgroup_ns into cgroup_fs_context
  cgroup1_get_tree(): separate "get cgroup_root to use" into a separate helper
  cgroup_do_mount(): massage calling conventions
  cgroup: stash cgroup_root reference into cgroup_fs_context
  cgroup2: switch to option-by-option parsing
  cgroup1: switch to option-by-option parsing
  cgroup: take options parsing into -&gt;parse_monolithic()
  cgroup: fold cgroup1_mount() into cgroup1_get_tree()
  cgroup: start switching to fs_context
  ipc: Convert mqueue fs to fs_context
  proc: Add fs_context support to procfs
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security</title>
<updated>2019-03-11T00:32:04+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-03-11T00:32:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=c3665a6be5de16cf6670a00003642114c44d8a70'/>
<id>c3665a6be5de16cf6670a00003642114c44d8a70</id>
<content type='text'>
Pull integrity updates from James Morris:
 "Mimi Zohar says:

   'Linux 5.0 introduced the platform keyring to allow verifying the IMA
    kexec kernel image signature using the pre-boot keys. This pull
    request similarly makes keys on the platform keyring accessible for
    verifying the PE kernel image signature.

    Also included in this pull request is a new IMA hook that tags tmp
    files, in policy, indicating the file hash needs to be calculated.
    The remaining patches are cleanup'"

* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  evm: Use defined constant for UUID representation
  ima: define ima_post_create_tmpfile() hook and add missing call
  evm: remove set but not used variable 'xattr'
  encrypted-keys: fix Opt_err/Opt_error = -1
  kexec, KEYS: Make use of platform keyring for signature verify
  integrity, KEYS: add a reference to platform keyring
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull integrity updates from James Morris:
 "Mimi Zohar says:

   'Linux 5.0 introduced the platform keyring to allow verifying the IMA
    kexec kernel image signature using the pre-boot keys. This pull
    request similarly makes keys on the platform keyring accessible for
    verifying the PE kernel image signature.

    Also included in this pull request is a new IMA hook that tags tmp
    files, in policy, indicating the file hash needs to be calculated.
    The remaining patches are cleanup'"

* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  evm: Use defined constant for UUID representation
  ima: define ima_post_create_tmpfile() hook and add missing call
  evm: remove set but not used variable 'xattr'
  encrypted-keys: fix Opt_err/Opt_error = -1
  kexec, KEYS: Make use of platform keyring for signature verify
  integrity, KEYS: add a reference to platform keyring
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'akpm' (patches from Andrew)</title>
<updated>2019-03-08T03:25:37+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-03-08T03:25:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=b5dd0c658c31b469ccff1b637e5124851e7a4a1c'/>
<id>b5dd0c658c31b469ccff1b637e5124851e7a4a1c</id>
<content type='text'>
Merge more updates from Andrew Morton:

 - some of the rest of MM

 - various misc things

 - dynamic-debug updates

 - checkpatch

 - some epoll speedups

 - autofs

 - rapidio

 - lib/, lib/lzo/ updates

* emailed patches from Andrew Morton &lt;akpm@linux-foundation.org&gt;: (83 commits)
  samples/mic/mpssd/mpssd.h: remove duplicate header
  kernel/fork.c: remove duplicated include
  include/linux/relay.h: fix percpu annotation in struct rchan
  arch/nios2/mm/fault.c: remove duplicate include
  unicore32: stop printing the virtual memory layout
  MAINTAINERS: fix GTA02 entry and mark as orphan
  mm: create the new vm_fault_t type
  arm, s390, unicore32: remove oneliner wrappers for memblock_alloc()
  arch: simplify several early memory allocations
  openrisc: simplify pte_alloc_one_kernel()
  sh: prefer memblock APIs returning virtual address
  microblaze: prefer memblock API returning virtual address
  powerpc: prefer memblock APIs returning virtual address
  lib/lzo: separate lzo-rle from lzo
  lib/lzo: implement run-length encoding
  lib/lzo: fast 8-byte copy on arm64
  lib/lzo: 64-bit CTZ on arm64
  lib/lzo: tidy-up ifdefs
  ipc/sem.c: replace kvmalloc/memset with kvzalloc and use struct_size
  ipc: annotate implicit fall through
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Merge more updates from Andrew Morton:

 - some of the rest of MM

 - various misc things

 - dynamic-debug updates

 - checkpatch

 - some epoll speedups

 - autofs

 - rapidio

 - lib/, lib/lzo/ updates

* emailed patches from Andrew Morton &lt;akpm@linux-foundation.org&gt;: (83 commits)
  samples/mic/mpssd/mpssd.h: remove duplicate header
  kernel/fork.c: remove duplicated include
  include/linux/relay.h: fix percpu annotation in struct rchan
  arch/nios2/mm/fault.c: remove duplicate include
  unicore32: stop printing the virtual memory layout
  MAINTAINERS: fix GTA02 entry and mark as orphan
  mm: create the new vm_fault_t type
  arm, s390, unicore32: remove oneliner wrappers for memblock_alloc()
  arch: simplify several early memory allocations
  openrisc: simplify pte_alloc_one_kernel()
  sh: prefer memblock APIs returning virtual address
  microblaze: prefer memblock API returning virtual address
  powerpc: prefer memblock APIs returning virtual address
  lib/lzo: separate lzo-rle from lzo
  lib/lzo: implement run-length encoding
  lib/lzo: fast 8-byte copy on arm64
  lib/lzo: 64-bit CTZ on arm64
  lib/lzo: tidy-up ifdefs
  ipc/sem.c: replace kvmalloc/memset with kvzalloc and use struct_size
  ipc: annotate implicit fall through
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>linux/fs.h: move member alignment check next to definition of struct filename</title>
<updated>2019-03-08T02:31:59+00:00</updated>
<author>
<name>Rasmus Villemoes</name>
<email>linux@rasmusvillemoes.dk</email>
</author>
<published>2019-03-08T00:27:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=f1fffbd44722cec9b8dd54d5cc86bd081ce39217'/>
<id>f1fffbd44722cec9b8dd54d5cc86bd081ce39217</id>
<content type='text'>
Instead of doing this compile-time check in some slightly arbitrary user
of struct filename, put it next to the definition.

Link: http://lkml.kernel.org/r/20190208203015.29702-3-linux@rasmusvillemoes.dk
Signed-off-by: Rasmus Villemoes &lt;linux@rasmusvillemoes.dk&gt;
Cc: Alexander Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Luc Van Oostenryck &lt;luc.vanoostenryck@gmail.com&gt;
Cc: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
Cc: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Cc: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Instead of doing this compile-time check in some slightly arbitrary user
of struct filename, put it next to the definition.

Link: http://lkml.kernel.org/r/20190208203015.29702-3-linux@rasmusvillemoes.dk
Signed-off-by: Rasmus Villemoes &lt;linux@rasmusvillemoes.dk&gt;
Cc: Alexander Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Luc Van Oostenryck &lt;luc.vanoostenryck@gmail.com&gt;
Cc: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
Cc: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Cc: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>vfs: Add configuration parser helpers</title>
<updated>2019-02-28T08:28:53+00:00</updated>
<author>
<name>David Howells</name>
<email>dhowells@redhat.com</email>
</author>
<published>2018-11-01T23:07:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=31d921c7fb9691722ba9503b64153cdc322a7fa8'/>
<id>31d921c7fb9691722ba9503b64153cdc322a7fa8</id>
<content type='text'>
Because the new API passes in key,value parameters, match_token() cannot be
used with it.  Instead, provide three new helpers to aid with parsing:

 (1) fs_parse().  This takes a parameter and a simple static description of
     all the parameters and maps the key name to an ID.  It returns 1 on a
     match, 0 on no match if unknowns should be ignored and some other
     negative error code on a parse error.

     The parameter description includes a list of key names to IDs, desired
     parameter types and a list of enumeration name -&gt; ID mappings.

     [!] Note that for the moment I've required that the key-&gt;ID mapping
     array is expected to be sorted and unterminated.  The size of the
     array is noted in the fsconfig_parser struct.  This allows me to use
     bsearch(), but I'm not sure any performance gain is worth the hassle
     of requiring people to keep the array sorted.

     The parameter type array is sized according to the number of parameter
     IDs and is indexed directly.  The optional enum mapping array is an
     unterminated, unsorted list and the size goes into the fsconfig_parser
     struct.

     The function can do some additional things:

	(a) If it's not ambiguous and no value is given, the prefix "no" on
	    a key name is permitted to indicate that the parameter should
	    be considered negatory.

	(b) If the desired type is a single simple integer, it will perform
	    an appropriate conversion and store the result in a union in
	    the parse result.

	(c) If the desired type is an enumeration, {key ID, name} will be
	    looked up in the enumeration list and the matching value will
	    be stored in the parse result union.

	(d) Optionally generate an error if the key is unrecognised.

     This is called something like:

	enum rdt_param {
		Opt_cdp,
		Opt_cdpl2,
		Opt_mba_mpbs,
		nr__rdt_params
	};

	const struct fs_parameter_spec rdt_param_specs[nr__rdt_params] = {
		[Opt_cdp]	= { fs_param_is_bool },
		[Opt_cdpl2]	= { fs_param_is_bool },
		[Opt_mba_mpbs]	= { fs_param_is_bool },
	};

	const const char *const rdt_param_keys[nr__rdt_params] = {
		[Opt_cdp]	= "cdp",
		[Opt_cdpl2]	= "cdpl2",
		[Opt_mba_mpbs]	= "mba_mbps",
	};

	const struct fs_parameter_description rdt_parser = {
		.name		= "rdt",
		.nr_params	= nr__rdt_params,
		.keys		= rdt_param_keys,
		.specs		= rdt_param_specs,
		.no_source	= true,
	};

	int rdt_parse_param(struct fs_context *fc,
			    struct fs_parameter *param)
	{
		struct fs_parse_result parse;
		struct rdt_fs_context *ctx = rdt_fc2context(fc);
		int ret;

		ret = fs_parse(fc, &amp;rdt_parser, param, &amp;parse);
		if (ret &lt; 0)
			return ret;

		switch (parse.key) {
		case Opt_cdp:
			ctx-&gt;enable_cdpl3 = true;
			return 0;
		case Opt_cdpl2:
			ctx-&gt;enable_cdpl2 = true;
			return 0;
		case Opt_mba_mpbs:
			ctx-&gt;enable_mba_mbps = true;
			return 0;
		}

		return -EINVAL;
	}

 (2) fs_lookup_param().  This takes a { dirfd, path, LOOKUP_EMPTY? } or
     string value and performs an appropriate path lookup to convert it
     into a path object, which it will then return.

     If the desired type was a blockdev, the type of the looked up inode
     will be checked to make sure it is one.

     This can be used like:

	enum foo_param {
		Opt_source,
		nr__foo_params
	};

	const struct fs_parameter_spec foo_param_specs[nr__foo_params] = {
		[Opt_source]	= { fs_param_is_blockdev },
	};

	const char *char foo_param_keys[nr__foo_params] = {
		[Opt_source]	= "source",
	};

	const struct constant_table foo_param_alt_keys[] = {
		{ "device",	Opt_source },
	};

	const struct fs_parameter_description foo_parser = {
		.name		= "foo",
		.nr_params	= nr__foo_params,
		.nr_alt_keys	= ARRAY_SIZE(foo_param_alt_keys),
		.keys		= foo_param_keys,
		.alt_keys	= foo_param_alt_keys,
		.specs		= foo_param_specs,
	};

	int foo_parse_param(struct fs_context *fc,
			    struct fs_parameter *param)
	{
		struct fs_parse_result parse;
		struct foo_fs_context *ctx = foo_fc2context(fc);
		int ret;

		ret = fs_parse(fc, &amp;foo_parser, param, &amp;parse);
		if (ret &lt; 0)
			return ret;

		switch (parse.key) {
		case Opt_source:
			return fs_lookup_param(fc, &amp;foo_parser, param,
					       &amp;parse, &amp;ctx-&gt;source);
		default:
			return -EINVAL;
		}
	}

 (3) lookup_constant().  This takes a table of named constants and looks up
     the given name within it.  The table is expected to be sorted such
     that bsearch() be used upon it.

     Possibly I should require the table be terminated and just use a
     for-loop to scan it instead of using bsearch() to reduce hassle.

     Tables look something like:

	static const struct constant_table bool_names[] = {
		{ "0",		false },
		{ "1",		true },
		{ "false",	false },
		{ "no",		false },
		{ "true",	true },
		{ "yes",	true },
	};

     and a lookup is done with something like:

	b = lookup_constant(bool_names, param-&gt;string, -1);

Additionally, optional validation routines for the parameter description
are provided that can be enabled at compile time.  A later patch will
invoke these when a filesystem is registered.

Signed-off-by: David Howells &lt;dhowells@redhat.com&gt;
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Because the new API passes in key,value parameters, match_token() cannot be
used with it.  Instead, provide three new helpers to aid with parsing:

 (1) fs_parse().  This takes a parameter and a simple static description of
     all the parameters and maps the key name to an ID.  It returns 1 on a
     match, 0 on no match if unknowns should be ignored and some other
     negative error code on a parse error.

     The parameter description includes a list of key names to IDs, desired
     parameter types and a list of enumeration name -&gt; ID mappings.

     [!] Note that for the moment I've required that the key-&gt;ID mapping
     array is expected to be sorted and unterminated.  The size of the
     array is noted in the fsconfig_parser struct.  This allows me to use
     bsearch(), but I'm not sure any performance gain is worth the hassle
     of requiring people to keep the array sorted.

     The parameter type array is sized according to the number of parameter
     IDs and is indexed directly.  The optional enum mapping array is an
     unterminated, unsorted list and the size goes into the fsconfig_parser
     struct.

     The function can do some additional things:

	(a) If it's not ambiguous and no value is given, the prefix "no" on
	    a key name is permitted to indicate that the parameter should
	    be considered negatory.

	(b) If the desired type is a single simple integer, it will perform
	    an appropriate conversion and store the result in a union in
	    the parse result.

	(c) If the desired type is an enumeration, {key ID, name} will be
	    looked up in the enumeration list and the matching value will
	    be stored in the parse result union.

	(d) Optionally generate an error if the key is unrecognised.

     This is called something like:

	enum rdt_param {
		Opt_cdp,
		Opt_cdpl2,
		Opt_mba_mpbs,
		nr__rdt_params
	};

	const struct fs_parameter_spec rdt_param_specs[nr__rdt_params] = {
		[Opt_cdp]	= { fs_param_is_bool },
		[Opt_cdpl2]	= { fs_param_is_bool },
		[Opt_mba_mpbs]	= { fs_param_is_bool },
	};

	const const char *const rdt_param_keys[nr__rdt_params] = {
		[Opt_cdp]	= "cdp",
		[Opt_cdpl2]	= "cdpl2",
		[Opt_mba_mpbs]	= "mba_mbps",
	};

	const struct fs_parameter_description rdt_parser = {
		.name		= "rdt",
		.nr_params	= nr__rdt_params,
		.keys		= rdt_param_keys,
		.specs		= rdt_param_specs,
		.no_source	= true,
	};

	int rdt_parse_param(struct fs_context *fc,
			    struct fs_parameter *param)
	{
		struct fs_parse_result parse;
		struct rdt_fs_context *ctx = rdt_fc2context(fc);
		int ret;

		ret = fs_parse(fc, &amp;rdt_parser, param, &amp;parse);
		if (ret &lt; 0)
			return ret;

		switch (parse.key) {
		case Opt_cdp:
			ctx-&gt;enable_cdpl3 = true;
			return 0;
		case Opt_cdpl2:
			ctx-&gt;enable_cdpl2 = true;
			return 0;
		case Opt_mba_mpbs:
			ctx-&gt;enable_mba_mbps = true;
			return 0;
		}

		return -EINVAL;
	}

 (2) fs_lookup_param().  This takes a { dirfd, path, LOOKUP_EMPTY? } or
     string value and performs an appropriate path lookup to convert it
     into a path object, which it will then return.

     If the desired type was a blockdev, the type of the looked up inode
     will be checked to make sure it is one.

     This can be used like:

	enum foo_param {
		Opt_source,
		nr__foo_params
	};

	const struct fs_parameter_spec foo_param_specs[nr__foo_params] = {
		[Opt_source]	= { fs_param_is_blockdev },
	};

	const char *char foo_param_keys[nr__foo_params] = {
		[Opt_source]	= "source",
	};

	const struct constant_table foo_param_alt_keys[] = {
		{ "device",	Opt_source },
	};

	const struct fs_parameter_description foo_parser = {
		.name		= "foo",
		.nr_params	= nr__foo_params,
		.nr_alt_keys	= ARRAY_SIZE(foo_param_alt_keys),
		.keys		= foo_param_keys,
		.alt_keys	= foo_param_alt_keys,
		.specs		= foo_param_specs,
	};

	int foo_parse_param(struct fs_context *fc,
			    struct fs_parameter *param)
	{
		struct fs_parse_result parse;
		struct foo_fs_context *ctx = foo_fc2context(fc);
		int ret;

		ret = fs_parse(fc, &amp;foo_parser, param, &amp;parse);
		if (ret &lt; 0)
			return ret;

		switch (parse.key) {
		case Opt_source:
			return fs_lookup_param(fc, &amp;foo_parser, param,
					       &amp;parse, &amp;ctx-&gt;source);
		default:
			return -EINVAL;
		}
	}

 (3) lookup_constant().  This takes a table of named constants and looks up
     the given name within it.  The table is expected to be sorted such
     that bsearch() be used upon it.

     Possibly I should require the table be terminated and just use a
     for-loop to scan it instead of using bsearch() to reduce hassle.

     Tables look something like:

	static const struct constant_table bool_names[] = {
		{ "0",		false },
		{ "1",		true },
		{ "false",	false },
		{ "no",		false },
		{ "true",	true },
		{ "yes",	true },
	};

     and a lookup is done with something like:

	b = lookup_constant(bool_names, param-&gt;string, -1);

Additionally, optional validation routines for the parameter description
are provided that can be enabled at compile time.  A later patch will
invoke these when a filesystem is registered.

Signed-off-by: David Howells &lt;dhowells@redhat.com&gt;
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</pre>
</div>
</content>
</entry>
</feed>
