Remove the old iget() call and the read_inode() superblock operation it uses
as these are really obsolete, and the use of read_inode() does not produce
proper error handling (no distinction between ENOMEM and EIO when marking an
inode bad).
Furthermore, this removes the temptation to use iget() to find an inode by
number in a filesystem from code outside that filesystem.
iget_locked() should be used instead. A new function is added in an earlier
patch (iget_failed) that is to be called to mark an inode as bad, unlock it
and release it should the get routine fail. Mark iget() and read_inode() as
being obsolete and remove references to them from the documentation.
Typically a filesystem will be modified such that the read_inode function
becomes an internal iget function, for example the following:
void thingyfs_read_inode(struct inode *inode)
{
...
}
would be changed into something like:
struct inode *thingyfs_iget(struct super_block *sp, unsigned long ino)
{
struct inode *inode;
int ret;
inode = iget_locked(sb, ino);
if (!inode)
return ERR_PTR(-ENOMEM);
if (!(inode->i_state & I_NEW))
return inode;
...
unlock_new_inode(inode);
return inode;
error:
iget_failed(inode);
return ERR_PTR(ret);
}
and then thingyfs_iget() would be called rather than iget(), for example:
ret = -EINVAL;
inode = iget(sb, ino);
if (!inode || is_bad_inode(inode))
goto error;
becomes:
inode = thingyfs_iget(sb, ino);
if (IS_ERR(inode)) {
ret = PTR_ERR(inode);
goto error;
}
Note that is_bad_inode() does not need to be called. The error returned by
thingyfs_iget() should render it unnecessary.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Stop the QNX4 filesystem from using iget() and read_inode(). Replace
qnx4_read_inode() with qnx4_iget(), and call that instead of iget().
qnx4_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.
qnx4_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Anders Larsen <al@alarsen.net>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Stop the EXT4 filesystem from using iget() and read_inode(). Replace
ext4_read_inode() with ext4_iget(), and call that instead of iget().
ext4_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.
ext4_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Acked-by: Jan Kara <jack@suse.cz>
Cc: <linux-ext4@vger.kernel.org>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Stop the EXT3 filesystem from using iget() and read_inode(). Replace
ext3_read_inode() with ext3_iget(), and call that instead of iget().
ext3_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.
ext3_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Acked-by: Jan Kara <jack@suse.cz>
Cc: <linux-ext4@vger.kernel.org>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Stop the EFS filesystem from using iget() and read_inode(). Replace
efs_read_inode() with efs_iget(), and call that instead of iget(). efs_iget()
then uses iget_locked() directly and returns a proper error code instead of an
inode in the event of an error.
efs_fill_super() returns any error incurred when getting the root inode
instead of EACCES.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Introduce a function to register failure in an inode construction path. This
includes marking the inode under construction as bad, unlocking it and
releasing it.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add an ERR_CAST() function to complement ERR_PTR and co. for the purposes
of casting an error entyped as one pointer type to an error of another
pointer type whilst making it explicit as to what is going on.
This provides a replacement for the ERR_PTR(PTR_ERR(p)) construct.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patchset is for the vmcoreinfo data.
The vmcoreinfo data has the minimum debugging information only for dump
filtering. makedumpfile (dump filtering command) gets it to distinguish
unnecessary pages, and makedumpfile creates a small dumpfile.
This patch:
VMCOREINFO_SIZE() should be renamed VMCOREINFO_STRUCT_SIZE() since it's always
returning the size of the struct with a given name. This change would allow
VMCOREINFO_TYPEDEF_SIZE() to simply become VMCOREINFO_SIZE() since it need not
be used exclusively for typedefs.
This discussion is the following:
http://www.ussg.iu.edu/hypermail/linux/kernel/0709.3/0582.html
Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patchset adds a flags variable to reserve_bootmem() and uses the
BOOTMEM_EXCLUSIVE flag in crashkernel reservation code to detect collisions
between crashkernel area and already used memory.
This patch:
Change the reserve_bootmem() function to accept a new flag BOOTMEM_EXCLUSIVE.
If that flag is set, the function returns with -EBUSY if the memory already
has been reserved in the past. This is to avoid conflicts.
Because that code runs before SMP initialisation, there's no race condition
inside reserve_bootmem_core().
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix powerpc build]
Signed-off-by: Bernhard Walle <bwalle@suse.de>
Cc: <linux-arch@vger.kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch corrects a situation that occurs when one disables all the cpus in
a cpuset.
Currently, the disabled (cpu-less) cpuset inherits the cpus of its parent,
which is incorrect because it may then overlap its cpu-exclusive sibling.
Tasks of an empty cpuset should be moved to the cpuset which is the parent of
their current cpuset. Or if the parent cpuset has no cpus, to its parent,
etc.
And the empty cpuset should be released (if it is flagged notify_on_release).
Depends on the cgroup_scan_tasks() function (proposed by David Rientjes) to
iterate through all tasks in the cpu-less cpuset. We are deliberately
avoiding a walk of the tasklist.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Cc: Paul Menage <menage@google.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Provide cgroup_scan_tasks(), which iterates through every task in a cgroup,
calling a test function and a process function for each. And call the process
function without holding the css_set_lock lock.
The idea is David Rientjes', predicting that such a function will make it much
easier in the future to extend things that require access to each task in a
cgroup without holding the lock,
[akpm@linux-foundation.org: cleanup]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Cc: Paul Menage <menage@google.com>
Cc: Paul Jackson <pj@sgi.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
While using memory control cgroup, page-migration under it works as following.
==
1. uncharge all refs at try to unmap.
2. charge regs again remove_migration_ptes()
==
This is simple but has following problems.
==
The page is uncharged and charged back again if *mapped*.
- This means that cgroup before migration can be different from one after
migration
- If page is not mapped but charged as page cache, charge is just ignored
(because not mapped, it will not be uncharged before migration)
This is memory leak.
==
This patch tries to keep memory cgroup at page migration by increasing
one refcnt during it. 3 functions are added.
mem_cgroup_prepare_migration() --- increase refcnt of page->page_cgroup
mem_cgroup_end_migration() --- decrease refcnt of page->page_cgroup
mem_cgroup_page_migration() --- copy page->page_cgroup from old page to
new page.
During migration
- old page is under PG_locked.
- new page is under PG_locked, too.
- both old page and new page is not on LRU.
These 3 facts guarantee that page_cgroup() migration has no race.
Tested and worked well in x86_64/fake-NUMA box.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Pavel Emelianov <xemul@openvz.org>
Cc: Paul Menage <menage@google.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Kirill Korotaev <dev@sw.ru>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: David Rientjes <rientjes@google.com>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
