linux-toradex.git/fs/libfs.c, branch v4.7 Linux kernel for Apalis and Colibri modules lockless next_positive() 2016-06-20T21:11:29+00:00 Al Viro viro@zeniv.linux.org.uk 2016-06-07T00:55:34+00:00 ebaaa80e8f20ff2cbbccd6823f73a99565487502 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> 
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
libfs.c: new helper - next_positive() 2016-06-20T21:11:28+00:00 Al Viro viro@zeniv.linux.org.uk 2016-06-06T23:37:13+00:00 4f42c1b5b9c27b6228e6b9c57eee4beb3118b6b0 Return nth positive child after given or NULL if there's less than n left. dcache_readdir() and dcache_dir_lseek() switched to it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> 
Return nth positive child after given or NULL if there's
less than n left.  dcache_readdir() and dcache_dir_lseek()
switched to it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
dcache_{readdir,dir_lseek}(): don't bother with nested ->d_lock 2016-06-20T21:11:26+00:00 Al Viro viro@zeniv.linux.org.uk 2016-06-06T22:55:57+00:00 274f5b041d3c9c0974a7dd1f66b67c33bb5b0f42 Make sure that directory is locked shared in dcache_dir_lseek(); for dcache_readdir() it's already tru, and that's enough to make simple_positive() stable. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> 
Make sure that directory is locked shared in dcache_dir_lseek();
for dcache_readdir() it's already tru, and that's enough to make
simple_positive() stable.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
much milder d_walk() race 2016-06-10T15:32:47+00:00 Al Viro viro@zeniv.linux.org.uk 2016-06-10T15:32:47+00:00 ba65dc5ef16f82fba77869cecf7a7d515f61446b d_walk() relies upon the tree not getting rearranged under it without rename_lock being touched. And we do grab rename_lock around the places that change the tree topology. Unfortunately, branch reordering is just as bad from d_walk() POV and we have two places that do it without touching rename_lock - one in handling of cursors (for ramfs-style directories) and another in autofs. autofs one is a separate story; this commit deals with the cursors. * mark cursor dentries explicitly at allocation time * make __dentry_kill() leave ->d_child.next pointing to the next non-cursor sibling, making sure that it won't be moved around unnoticed before the parent is relocked on ascend-to-parent path in d_walk(). * make d_walk() skip cursors explicitly; strictly speaking it's not necessary (all callbacks we pass to d_walk() are no-ops on cursors), but it makes analysis easier. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> 
d_walk() relies upon the tree not getting rearranged under it without
rename_lock being touched.  And we do grab rename_lock around the
places that change the tree topology.  Unfortunately, branch reordering
is just as bad from d_walk() POV and we have two places that do it
without touching rename_lock - one in handling of cursors (for ramfs-style
directories) and another in autofs.  autofs one is a separate story; this
commit deals with the cursors.
	* mark cursor dentries explicitly at allocation time
	* make __dentry_kill() leave ->d_child.next pointing to the next
non-cursor sibling, making sure that it won't be moved around unnoticed
before the parent is relocked on ascend-to-parent path in d_walk().
	* make d_walk() skip cursors explicitly; strictly speaking it's
not necessary (all callbacks we pass to d_walk() are no-ops on cursors),
but it makes analysis easier.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
switch ->setxattr() to passing dentry and inode separately 2016-05-28T00:09:16+00:00 Al Viro viro@zeniv.linux.org.uk 2016-05-27T15:06:05+00:00 3767e255b390d72f9a33c08d9e86c5f21f25860f smack ->d_instantiate() uses ->setxattr(), so to be able to call it before we'd hashed the new dentry and attached it to inode, we need ->setxattr() instances getting the inode as an explicit argument rather than obtaining it from dentry. Similar change for ->getxattr() had been done in commit ce23e64. Unlike ->getxattr() (which is used by both selinux and smack instances of ->d_instantiate()) ->setxattr() is used only by smack one and unfortunately it got missed back then. Reported-by: Seung-Woo Kim <sw0312.kim@samsung.com> Tested-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> 
smack ->d_instantiate() uses ->setxattr(), so to be able to call it before
we'd hashed the new dentry and attached it to inode, we need ->setxattr()
instances getting the inode as an explicit argument rather than obtaining
it from dentry.

Similar change for ->getxattr() had been done in commit ce23e64.  Unlike
->getxattr() (which is used by both selinux and smack instances of
->d_instantiate()) ->setxattr() is used only by smack one and unfortunately
it got missed back then.

Reported-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Tested-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
more trivial ->iterate_shared conversions 2016-05-09T15:41:14+00:00 Al Viro viro@zeniv.linux.org.uk 2016-05-01T02:37:34+00:00 c51da20c48b76ef1114d14b6b6ff190e11afab0e Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> 
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
dcache_{readdir,dir_lseek}() users: switch to ->iterate_shared 2016-05-02T23:49:32+00:00 Al Viro viro@zeniv.linux.org.uk 2016-04-20T23:52:15+00:00 4e82901cd6d1af21ae232ae835c36d8230c809e8 no need to lock directory in dcache_dir_lseek(), while we are at it - per-struct file exclusion is enough. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> 
no need to lock directory in dcache_dir_lseek(), while we are
at it - per-struct file exclusion is enough.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Merge getxattr prototype change into work.lookups 2016-05-02T23:45:47+00:00 Al Viro viro@zeniv.linux.org.uk 2016-05-02T23:45:47+00:00 84695ffee7987ee1e581be4c4696e47e1a29403b The rest of work.xattr stuff isn't needed for this branch 
The rest of work.xattr stuff isn't needed for this branch
->getxattr(): pass dentry and inode as separate arguments 2016-04-11T04:48:00+00:00 Al Viro viro@zeniv.linux.org.uk 2016-04-11T04:48:00+00:00 ce23e640133484eebc20ca7b7668388213e11327 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> 
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros 2016-04-04T17:41:08+00:00 Kirill A. Shutemov kirill.shutemov@linux.intel.com 2016-04-01T12:29:47+00:00 09cbfeaf1a5a67bfb3201e0c83c810cecb2efa5a PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>