user/sven/linux.git/include/linux/shmem_fs.h, branch tmp/leds/core

[PATCH] sanitize ->permission() prototype

2008-07-27T00:53:14Z

* kill nameidata * argument; map the 3 bits in ->flags anybody cares about to new MAY_... ones and pass with the mask. * kill redundant gfs2_iop_permission() * sanitize ecryptfs_permission() * fix remaining places where ->permission() instances might barf on new MAY_... found in mask. The obvious next target in that direction is permission(9) folded fix for nfs_permission() breakage from Miklos Szeredi Signed-off-by: Al Viro

mempolicy: use struct mempolicy pointer in shmem_sb_info

2008-04-28T15:58:25Z

This patch replaces the mempolicy mode, mode_flags, and nodemask in the shmem_sb_info struct with a struct mempolicy pointer, initialized to NULL. This removes dependency on the details of mempolicy from shmem.c and hugetlbfs inode.c and simplifies the interfaces. mpol_parse_str() in mempolicy.c is changed to return, via a pointer to a pointer arg, a struct mempolicy pointer on success. For MPOL_DEFAULT, the returned pointer is NULL. Further, mpol_parse_str() now takes a 'no_context' argument that causes the input nodemask to be stored in the w.user_nodemask of the created mempolicy for use when the mempolicy is installed in a tmpfs inode shared policy tree. At that time, any cpuset contextualization is applied to the original input nodemask. This preserves the previous behavior where the input nodemask was stored in the superblock. We can think of the returned mempolicy as "context free". Because mpol_parse_str() is now calling mpol_new(), we can remove from mpol_to_str() the semantic checks that mpol_new() already performs. Add 'no_context' parameter to mpol_to_str() to specify that it should format the nodemask in w.user_nodemask for 'bind' and 'interleave' policies. Change mpol_shared_policy_init() to take a pointer to a "context free" struct mempolicy and to create a new, "contextualized" mempolicy using the mode, mode_flags and user_nodemask from the input mempolicy. Note: we know that the mempolicy passed to mpol_to_str() or mpol_shared_policy_init() from a tmpfs superblock is "context free". This is currently the only instance thereof. However, if we found more uses for this concept, and introduced any ambiguity as to whether a mempolicy was context free or not, we could add another internal mode flag to identify context free mempolicies. Then, we could remove the 'no_context' argument from mpol_to_str(). Added shmem_get_sbmpol() to return a reference counted superblock mempolicy, if one exists, to pass to mpol_shared_policy_init(). We must add the reference under the sb stat_lock to prevent races with replacement of the mpol by remount. This reference is removed in mpol_shared_policy_init(). [akpm@linux-foundation.org: build fix] [akpm@linux-foundation.org: another build fix] [akpm@linux-foundation.org: yet another build fix] Signed-off-by: Lee Schermerhorn Cc: Christoph Lameter Cc: David Rientjes Cc: Mel Gorman Cc: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mempolicy: support optional mode flags

2008-04-28T15:58:19Z

With the evolution of mempolicies, it is necessary to support mempolicy mode flags that specify how the policy shall behave in certain circumstances. The most immediate need for mode flag support is to suppress remapping the nodemask of a policy at the time of rebind. Both the mempolicy mode and flags are passed by the user in the 'int policy' formal of either the set_mempolicy() or mbind() syscall. A new constant, MPOL_MODE_FLAGS, represents the union of legal optional flags that may be passed as part of this int. Mempolicies that include illegal flags as part of their policy are rejected as invalid. An additional member to struct mempolicy is added to support the mode flags: struct mempolicy { ... unsigned short policy; unsigned short flags; } The splitting of the 'int' actual passed by the user is done in sys_set_mempolicy() and sys_mbind() for their respective syscalls. This is done by intersecting the actual with MPOL_MODE_FLAGS, rejecting the syscall of there are additional flags, and storing it in the new 'flags' member of struct mempolicy. The intersection of the actual with ~MPOL_MODE_FLAGS is stored in the 'policy' member of the struct and all current users of pol->policy remain unchanged. The union of the policy mode and optional mode flags is passed back to the user in get_mempolicy(). This combination of mode and flags within the same actual does not break userspace code that relies on get_mempolicy(&policy, ...) and either switch (policy) { case MPOL_BIND: ... case MPOL_INTERLEAVE: ... }; statements or if (policy == MPOL_INTERLEAVE) { ... } statements. Such applications would need to use optional mode flags when calling set_mempolicy() or mbind() for these previously implemented statements to stop working. If an application does start using optional mode flags, it will need to mask the optional flags off the policy in switch and conditional statements that only test mode. An additional member is also added to struct shmem_sb_info to store the optional mode flags. [hugh@veritas.com: shmem mpol: fix build warning] Cc: Paul Jackson Cc: Christoph Lameter Cc: Lee Schermerhorn Cc: Andi Kleen Signed-off-by: David Rientjes Signed-off-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mempolicy: convert MPOL constants to enum

2008-04-28T15:58:19Z

The mempolicy mode constants, MPOL_DEFAULT, MPOL_PREFERRED, MPOL_BIND, and MPOL_INTERLEAVE, are better declared as part of an enum since they are sequentially numbered and cannot be combined. The policy member of struct mempolicy is also converted from type short to type unsigned short. A negative policy does not have any legitimate meaning, so it is possible to change its type in preparation for adding optional mode flags later. The equivalent member of struct shmem_sb_info is also changed from int to unsigned short. For compatibility, the policy formal to get_mempolicy() remains as a pointer to an int: int get_mempolicy(int *policy, unsigned long *nmask, unsigned long maxnode, unsigned long addr, unsigned long flags); although the only possible values is the range of type unsigned short. Cc: Paul Jackson Cc: Christoph Lameter Cc: Lee Schermerhorn Cc: Andi Kleen Signed-off-by: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mount options: fix tmpfs

2008-02-08T17:22:41Z

Add .show_options super operation to tmpfs. Signed-off-by: Hugh Dickins Signed-off-by: Miklos Szeredi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] Access Control Lists for tmpfs

2006-09-29T16:18:24Z

Add access control lists for tmpfs. Signed-off-by: Andreas Gruenbacher Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] Add tmpfs options for memory placement policies

2006-01-15T02:27:07Z

Anything that writes into a tmpfs filesystem is liable to disproportionately decrease the available memory on a particular node. Since there's no telling what sort of application (e.g. dd/cp/cat) might be dropping large files there, this lets the admin choose the appropriate default behavior for their site's situation. Introduce a tmpfs mount option which allows specifying a memory policy and a second option to specify the nodelist for that policy. With the default policy, tmpfs will behave as it does today. This patch adds support for preferred, bind, and interleave policies. The default policy will cause pages to be added to tmpfs files on the node which is doing the writing. Some jobs expect a single process to create and manage the tmpfs files. This results in a node which has a significantly reduced number of free pages. With this patch, the administrator can specify the policy and nodes for that policy where they would prefer allocations. This patch was originally written by Brent Casavant and Hugh Dickins. I added support for the bind and preferred policies and the mpol_nodelist mount option. Signed-off-by: Brent Casavant Signed-off-by: Hugh Dickins Signed-off-by: Robin Holt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] shmem: avoid the shmem_inodes list

2004-09-14T00:46:13Z

If we're thinking about shmem scalability... isn't it silly that each shmem object is added to the shmem_inodes list on creation, and removed on deletion, yet the only use for that list is in swapoff (shmem_unuse)? Call it shmem_swaplist; shmem_writepage add inode to swaplist when first swap allocated (usually never); shmem_delete_inode remove inode from the list after truncating (if called before, inode could be re-added to it). Inode can remain on the swaplist after all its pages are swapped back in, just be lazy about it; but if shmem_unuse finds swapped count now 0, save itself time by then removing that inode from the swaplist. Signed-off-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] shmem: don't SLAB_HWCACHE_ALIGN

2004-09-14T00:45:23Z

Anton recently removed SLAB_HWCACHE_ALIGN from the fs inode caches, now do the same for tmpfs inode cache: fits 9 per page where 7 before. Was saying SLAB_RECLAIM_ACCOUNT too, but that's wrong: tmpfs inodes are not reclaimed under pressure; and hugetlbfs had copied that too. Rearrange shmem_inode_info fields so those most likely to be needed are most likely to be in the same cacheline as the spinlock guarding them. Signed-off-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] numa api: Add shared memory support

2004-05-22T15:04:40Z

From: Andi Kleen Add support to tmpfs and hugetlbfs to support NUMA API. Shared memory is a bit of a special case for NUMA policy. Normally policy is associated to VMAs or to processes, but for a shared memory segment you really want to share the policy. The core NUMA API has code for that, this patch adds the necessary changes to tmpfs and hugetlbfs. First it changes the custom swapping code in tmpfs to follow the policy set via VMAs. It is also useful to have a "backing store" of policy that saves the policy even when nobody has the shared memory segment mapped. This allows command line tools to pre configure policy, which is then later used by programs. Note that hugetlbfs needs more changes - it is also required to switch it to lazy allocation, otherwise the prefault prevents mbind() from working.