![Souptick Joarder](/assets/img/avatar_default.png)
The plan for these patches is to introduce the typedef, initially just as documentation ("These functions should return a VM_FAULT_ status"). We'll trickle the patches to individual drivers/filesystems in through the maintainers, as far as possible. Then we'll change the typedef to an unsigned int and break the compilation of any unconverted drivers/filesystems. vmf_insert_page(), vmf_insert_mixed() and vmf_insert_pfn() are three newly added functions. The various drivers/filesystems where return value of fault(), huge_fault(), page_mkwrite() and pfn_mkwrite() get converted, will need them. These functions will return correct VM_FAULT_ code based on err value. We've had bugs before where drivers returned -EFOO. And we have this silly inefficiency where vm_insert_xxx() return an errno which (afaict) every driver then converts into a VM_FAULT code. In many cases drivers failed to return correct VM_FAULT code value despite of vm_insert_xxx() fails. We have indentified and clean up all those existing bugs and silly inefficiencies in driver/filesystems by adding these three new inline wrappers. As mentioned above, we will trickle those patches to individual drivers/filesystems in through maintainers after these three wrapper functions are merged. Eventually we can convert vm_insert_xxx() into vmf_insert_xxx() and remove these inline wrappers, but these are a good intermediate step. Link: http://lkml.kernel.org/r/20180310162351.GA7422@jordon-HP-15-Notebook-PC Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
656 lines
20 KiB
C
656 lines
20 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _LINUX_MM_TYPES_H
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#define _LINUX_MM_TYPES_H
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#include <linux/mm_types_task.h>
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#include <linux/auxvec.h>
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#include <linux/list.h>
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#include <linux/spinlock.h>
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#include <linux/rbtree.h>
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#include <linux/rwsem.h>
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#include <linux/completion.h>
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#include <linux/cpumask.h>
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#include <linux/uprobes.h>
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#include <linux/page-flags-layout.h>
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#include <linux/workqueue.h>
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#include <asm/mmu.h>
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#ifndef AT_VECTOR_SIZE_ARCH
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#define AT_VECTOR_SIZE_ARCH 0
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#endif
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#define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1))
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typedef int vm_fault_t;
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struct address_space;
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struct mem_cgroup;
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struct hmm;
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/*
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* Each physical page in the system has a struct page associated with
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* it to keep track of whatever it is we are using the page for at the
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* moment. Note that we have no way to track which tasks are using
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* a page, though if it is a pagecache page, rmap structures can tell us
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* who is mapping it. If you allocate the page using alloc_pages(), you
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* can use some of the space in struct page for your own purposes.
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*
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* Pages that were once in the page cache may be found under the RCU lock
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* even after they have been recycled to a different purpose. The page
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* cache reads and writes some of the fields in struct page to pin the
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* page before checking that it's still in the page cache. It is vital
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* that all users of struct page:
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* 1. Use the first word as PageFlags.
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* 2. Clear or preserve bit 0 of page->compound_head. It is used as
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* PageTail for compound pages, and the page cache must not see false
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* positives. Some users put a pointer here (guaranteed to be at least
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* 4-byte aligned), other users avoid using the field altogether.
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* 3. page->_refcount must either not be used, or must be used in such a
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* way that other CPUs temporarily incrementing and then decrementing the
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* refcount does not cause problems. On receiving the page from
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* alloc_pages(), the refcount will be positive.
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* 4. Either preserve page->_mapcount or restore it to -1 before freeing it.
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*
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* If you allocate pages of order > 0, you can use the fields in the struct
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* page associated with each page, but bear in mind that the pages may have
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* been inserted individually into the page cache, so you must use the above
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* four fields in a compatible way for each struct page.
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*
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* SLUB uses cmpxchg_double() to atomically update its freelist and
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* counters. That requires that freelist & counters be adjacent and
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* double-word aligned. We align all struct pages to double-word
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* boundaries, and ensure that 'freelist' is aligned within the
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* struct.
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*/
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#ifdef CONFIG_HAVE_ALIGNED_STRUCT_PAGE
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#define _struct_page_alignment __aligned(2 * sizeof(unsigned long))
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#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE)
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#define _slub_counter_t unsigned long
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#else
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#define _slub_counter_t unsigned int
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#endif
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#else /* !CONFIG_HAVE_ALIGNED_STRUCT_PAGE */
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#define _struct_page_alignment
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#define _slub_counter_t unsigned int
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#endif /* !CONFIG_HAVE_ALIGNED_STRUCT_PAGE */
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struct page {
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/* First double word block */
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unsigned long flags; /* Atomic flags, some possibly
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* updated asynchronously */
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union {
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/* See page-flags.h for the definition of PAGE_MAPPING_FLAGS */
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struct address_space *mapping;
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void *s_mem; /* slab first object */
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atomic_t compound_mapcount; /* first tail page */
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/* page_deferred_list().next -- second tail page */
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};
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/* Second double word */
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union {
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pgoff_t index; /* Our offset within mapping. */
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void *freelist; /* sl[aou]b first free object */
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/* page_deferred_list().prev -- second tail page */
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};
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union {
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_slub_counter_t counters;
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unsigned int active; /* SLAB */
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struct { /* SLUB */
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unsigned inuse:16;
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unsigned objects:15;
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unsigned frozen:1;
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};
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int units; /* SLOB */
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struct { /* Page cache */
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/*
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* Count of ptes mapped in mms, to show when
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* page is mapped & limit reverse map searches.
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*
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* Extra information about page type may be
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* stored here for pages that are never mapped,
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* in which case the value MUST BE <= -2.
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* See page-flags.h for more details.
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*/
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atomic_t _mapcount;
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/*
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* Usage count, *USE WRAPPER FUNCTION* when manual
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* accounting. See page_ref.h
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*/
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atomic_t _refcount;
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};
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};
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/*
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* WARNING: bit 0 of the first word encode PageTail(). That means
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* the rest users of the storage space MUST NOT use the bit to
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* avoid collision and false-positive PageTail().
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*/
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union {
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struct list_head lru; /* Pageout list, eg. active_list
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* protected by zone_lru_lock !
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* Can be used as a generic list
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* by the page owner.
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*/
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struct dev_pagemap *pgmap; /* ZONE_DEVICE pages are never on an
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* lru or handled by a slab
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* allocator, this points to the
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* hosting device page map.
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*/
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struct { /* slub per cpu partial pages */
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struct page *next; /* Next partial slab */
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#ifdef CONFIG_64BIT
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int pages; /* Nr of partial slabs left */
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int pobjects; /* Approximate # of objects */
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#else
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short int pages;
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short int pobjects;
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#endif
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};
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struct rcu_head rcu_head; /* Used by SLAB
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* when destroying via RCU
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*/
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/* Tail pages of compound page */
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struct {
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unsigned long compound_head; /* If bit zero is set */
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/* First tail page only */
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unsigned char compound_dtor;
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unsigned char compound_order;
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/* two/six bytes available here */
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};
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#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && USE_SPLIT_PMD_PTLOCKS
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struct {
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unsigned long __pad; /* do not overlay pmd_huge_pte
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* with compound_head to avoid
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* possible bit 0 collision.
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*/
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pgtable_t pmd_huge_pte; /* protected by page->ptl */
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};
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#endif
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};
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union {
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/*
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* Mapping-private opaque data:
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* Usually used for buffer_heads if PagePrivate
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* Used for swp_entry_t if PageSwapCache
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* Indicates order in the buddy system if PageBuddy
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*/
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unsigned long private;
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#if USE_SPLIT_PTE_PTLOCKS
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#if ALLOC_SPLIT_PTLOCKS
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spinlock_t *ptl;
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#else
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spinlock_t ptl;
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#endif
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#endif
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struct kmem_cache *slab_cache; /* SL[AU]B: Pointer to slab */
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};
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#ifdef CONFIG_MEMCG
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struct mem_cgroup *mem_cgroup;
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#endif
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/*
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* On machines where all RAM is mapped into kernel address space,
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* we can simply calculate the virtual address. On machines with
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* highmem some memory is mapped into kernel virtual memory
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* dynamically, so we need a place to store that address.
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* Note that this field could be 16 bits on x86 ... ;)
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*
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* Architectures with slow multiplication can define
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* WANT_PAGE_VIRTUAL in asm/page.h
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*/
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#if defined(WANT_PAGE_VIRTUAL)
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void *virtual; /* Kernel virtual address (NULL if
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not kmapped, ie. highmem) */
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#endif /* WANT_PAGE_VIRTUAL */
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#ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
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int _last_cpupid;
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#endif
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} _struct_page_alignment;
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#define PAGE_FRAG_CACHE_MAX_SIZE __ALIGN_MASK(32768, ~PAGE_MASK)
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#define PAGE_FRAG_CACHE_MAX_ORDER get_order(PAGE_FRAG_CACHE_MAX_SIZE)
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struct page_frag_cache {
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void * va;
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#if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE)
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__u16 offset;
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__u16 size;
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#else
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__u32 offset;
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#endif
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/* we maintain a pagecount bias, so that we dont dirty cache line
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* containing page->_refcount every time we allocate a fragment.
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*/
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unsigned int pagecnt_bias;
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bool pfmemalloc;
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};
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typedef unsigned long vm_flags_t;
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/*
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* A region containing a mapping of a non-memory backed file under NOMMU
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* conditions. These are held in a global tree and are pinned by the VMAs that
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* map parts of them.
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*/
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struct vm_region {
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struct rb_node vm_rb; /* link in global region tree */
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vm_flags_t vm_flags; /* VMA vm_flags */
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unsigned long vm_start; /* start address of region */
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unsigned long vm_end; /* region initialised to here */
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unsigned long vm_top; /* region allocated to here */
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unsigned long vm_pgoff; /* the offset in vm_file corresponding to vm_start */
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struct file *vm_file; /* the backing file or NULL */
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int vm_usage; /* region usage count (access under nommu_region_sem) */
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bool vm_icache_flushed : 1; /* true if the icache has been flushed for
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* this region */
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};
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#ifdef CONFIG_USERFAULTFD
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#define NULL_VM_UFFD_CTX ((struct vm_userfaultfd_ctx) { NULL, })
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struct vm_userfaultfd_ctx {
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struct userfaultfd_ctx *ctx;
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};
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#else /* CONFIG_USERFAULTFD */
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#define NULL_VM_UFFD_CTX ((struct vm_userfaultfd_ctx) {})
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struct vm_userfaultfd_ctx {};
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#endif /* CONFIG_USERFAULTFD */
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/*
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* This struct defines a memory VMM memory area. There is one of these
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* per VM-area/task. A VM area is any part of the process virtual memory
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* space that has a special rule for the page-fault handlers (ie a shared
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* library, the executable area etc).
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*/
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struct vm_area_struct {
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/* The first cache line has the info for VMA tree walking. */
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unsigned long vm_start; /* Our start address within vm_mm. */
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unsigned long vm_end; /* The first byte after our end address
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within vm_mm. */
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/* linked list of VM areas per task, sorted by address */
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struct vm_area_struct *vm_next, *vm_prev;
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struct rb_node vm_rb;
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/*
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* Largest free memory gap in bytes to the left of this VMA.
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* Either between this VMA and vma->vm_prev, or between one of the
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* VMAs below us in the VMA rbtree and its ->vm_prev. This helps
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* get_unmapped_area find a free area of the right size.
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*/
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unsigned long rb_subtree_gap;
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/* Second cache line starts here. */
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struct mm_struct *vm_mm; /* The address space we belong to. */
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pgprot_t vm_page_prot; /* Access permissions of this VMA. */
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unsigned long vm_flags; /* Flags, see mm.h. */
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/*
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* For areas with an address space and backing store,
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* linkage into the address_space->i_mmap interval tree.
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*/
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struct {
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struct rb_node rb;
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unsigned long rb_subtree_last;
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} shared;
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/*
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* A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma
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* list, after a COW of one of the file pages. A MAP_SHARED vma
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* can only be in the i_mmap tree. An anonymous MAP_PRIVATE, stack
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* or brk vma (with NULL file) can only be in an anon_vma list.
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*/
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struct list_head anon_vma_chain; /* Serialized by mmap_sem &
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* page_table_lock */
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struct anon_vma *anon_vma; /* Serialized by page_table_lock */
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/* Function pointers to deal with this struct. */
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const struct vm_operations_struct *vm_ops;
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/* Information about our backing store: */
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unsigned long vm_pgoff; /* Offset (within vm_file) in PAGE_SIZE
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units */
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struct file * vm_file; /* File we map to (can be NULL). */
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void * vm_private_data; /* was vm_pte (shared mem) */
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atomic_long_t swap_readahead_info;
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#ifndef CONFIG_MMU
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struct vm_region *vm_region; /* NOMMU mapping region */
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#endif
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#ifdef CONFIG_NUMA
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struct mempolicy *vm_policy; /* NUMA policy for the VMA */
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#endif
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struct vm_userfaultfd_ctx vm_userfaultfd_ctx;
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} __randomize_layout;
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struct core_thread {
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struct task_struct *task;
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struct core_thread *next;
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};
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struct core_state {
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atomic_t nr_threads;
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struct core_thread dumper;
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struct completion startup;
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};
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struct kioctx_table;
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struct mm_struct {
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struct vm_area_struct *mmap; /* list of VMAs */
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struct rb_root mm_rb;
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u32 vmacache_seqnum; /* per-thread vmacache */
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#ifdef CONFIG_MMU
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unsigned long (*get_unmapped_area) (struct file *filp,
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unsigned long addr, unsigned long len,
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unsigned long pgoff, unsigned long flags);
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#endif
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unsigned long mmap_base; /* base of mmap area */
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unsigned long mmap_legacy_base; /* base of mmap area in bottom-up allocations */
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#ifdef CONFIG_HAVE_ARCH_COMPAT_MMAP_BASES
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/* Base adresses for compatible mmap() */
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unsigned long mmap_compat_base;
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unsigned long mmap_compat_legacy_base;
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#endif
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unsigned long task_size; /* size of task vm space */
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unsigned long highest_vm_end; /* highest vma end address */
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pgd_t * pgd;
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/**
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* @mm_users: The number of users including userspace.
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*
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* Use mmget()/mmget_not_zero()/mmput() to modify. When this drops
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* to 0 (i.e. when the task exits and there are no other temporary
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* reference holders), we also release a reference on @mm_count
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* (which may then free the &struct mm_struct if @mm_count also
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* drops to 0).
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*/
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atomic_t mm_users;
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/**
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* @mm_count: The number of references to &struct mm_struct
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* (@mm_users count as 1).
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*
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* Use mmgrab()/mmdrop() to modify. When this drops to 0, the
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* &struct mm_struct is freed.
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*/
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atomic_t mm_count;
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#ifdef CONFIG_MMU
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atomic_long_t pgtables_bytes; /* PTE page table pages */
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#endif
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int map_count; /* number of VMAs */
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spinlock_t page_table_lock; /* Protects page tables and some counters */
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struct rw_semaphore mmap_sem;
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struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung
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* together off init_mm.mmlist, and are protected
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* by mmlist_lock
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*/
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unsigned long hiwater_rss; /* High-watermark of RSS usage */
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unsigned long hiwater_vm; /* High-water virtual memory usage */
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unsigned long total_vm; /* Total pages mapped */
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unsigned long locked_vm; /* Pages that have PG_mlocked set */
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unsigned long pinned_vm; /* Refcount permanently increased */
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unsigned long data_vm; /* VM_WRITE & ~VM_SHARED & ~VM_STACK */
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unsigned long exec_vm; /* VM_EXEC & ~VM_WRITE & ~VM_STACK */
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unsigned long stack_vm; /* VM_STACK */
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unsigned long def_flags;
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unsigned long start_code, end_code, start_data, end_data;
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unsigned long start_brk, brk, start_stack;
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unsigned long arg_start, arg_end, env_start, env_end;
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unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
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/*
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* Special counters, in some configurations protected by the
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* page_table_lock, in other configurations by being atomic.
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*/
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struct mm_rss_stat rss_stat;
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struct linux_binfmt *binfmt;
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cpumask_var_t cpu_vm_mask_var;
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/* Architecture-specific MM context */
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mm_context_t context;
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unsigned long flags; /* Must use atomic bitops to access the bits */
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struct core_state *core_state; /* coredumping support */
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#ifdef CONFIG_MEMBARRIER
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atomic_t membarrier_state;
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#endif
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#ifdef CONFIG_AIO
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spinlock_t ioctx_lock;
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struct kioctx_table __rcu *ioctx_table;
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#endif
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#ifdef CONFIG_MEMCG
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/*
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* "owner" points to a task that is regarded as the canonical
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* user/owner of this mm. All of the following must be true in
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* order for it to be changed:
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*
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* current == mm->owner
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* current->mm != mm
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* new_owner->mm == mm
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* new_owner->alloc_lock is held
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*/
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struct task_struct __rcu *owner;
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#endif
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struct user_namespace *user_ns;
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/* store ref to file /proc/<pid>/exe symlink points to */
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struct file __rcu *exe_file;
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#ifdef CONFIG_MMU_NOTIFIER
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struct mmu_notifier_mm *mmu_notifier_mm;
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#endif
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#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && !USE_SPLIT_PMD_PTLOCKS
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pgtable_t pmd_huge_pte; /* protected by page_table_lock */
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#endif
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#ifdef CONFIG_CPUMASK_OFFSTACK
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struct cpumask cpumask_allocation;
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#endif
|
|
#ifdef CONFIG_NUMA_BALANCING
|
|
/*
|
|
* numa_next_scan is the next time that the PTEs will be marked
|
|
* pte_numa. NUMA hinting faults will gather statistics and migrate
|
|
* pages to new nodes if necessary.
|
|
*/
|
|
unsigned long numa_next_scan;
|
|
|
|
/* Restart point for scanning and setting pte_numa */
|
|
unsigned long numa_scan_offset;
|
|
|
|
/* numa_scan_seq prevents two threads setting pte_numa */
|
|
int numa_scan_seq;
|
|
#endif
|
|
/*
|
|
* An operation with batched TLB flushing is going on. Anything that
|
|
* can move process memory needs to flush the TLB when moving a
|
|
* PROT_NONE or PROT_NUMA mapped page.
|
|
*/
|
|
atomic_t tlb_flush_pending;
|
|
#ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
|
|
/* See flush_tlb_batched_pending() */
|
|
bool tlb_flush_batched;
|
|
#endif
|
|
struct uprobes_state uprobes_state;
|
|
#ifdef CONFIG_HUGETLB_PAGE
|
|
atomic_long_t hugetlb_usage;
|
|
#endif
|
|
struct work_struct async_put_work;
|
|
|
|
#if IS_ENABLED(CONFIG_HMM)
|
|
/* HMM needs to track a few things per mm */
|
|
struct hmm *hmm;
|
|
#endif
|
|
} __randomize_layout;
|
|
|
|
extern struct mm_struct init_mm;
|
|
|
|
static inline void mm_init_cpumask(struct mm_struct *mm)
|
|
{
|
|
#ifdef CONFIG_CPUMASK_OFFSTACK
|
|
mm->cpu_vm_mask_var = &mm->cpumask_allocation;
|
|
#endif
|
|
cpumask_clear(mm->cpu_vm_mask_var);
|
|
}
|
|
|
|
/* Future-safe accessor for struct mm_struct's cpu_vm_mask. */
|
|
static inline cpumask_t *mm_cpumask(struct mm_struct *mm)
|
|
{
|
|
return mm->cpu_vm_mask_var;
|
|
}
|
|
|
|
struct mmu_gather;
|
|
extern void tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm,
|
|
unsigned long start, unsigned long end);
|
|
extern void tlb_finish_mmu(struct mmu_gather *tlb,
|
|
unsigned long start, unsigned long end);
|
|
|
|
static inline void init_tlb_flush_pending(struct mm_struct *mm)
|
|
{
|
|
atomic_set(&mm->tlb_flush_pending, 0);
|
|
}
|
|
|
|
static inline void inc_tlb_flush_pending(struct mm_struct *mm)
|
|
{
|
|
atomic_inc(&mm->tlb_flush_pending);
|
|
/*
|
|
* The only time this value is relevant is when there are indeed pages
|
|
* to flush. And we'll only flush pages after changing them, which
|
|
* requires the PTL.
|
|
*
|
|
* So the ordering here is:
|
|
*
|
|
* atomic_inc(&mm->tlb_flush_pending);
|
|
* spin_lock(&ptl);
|
|
* ...
|
|
* set_pte_at();
|
|
* spin_unlock(&ptl);
|
|
*
|
|
* spin_lock(&ptl)
|
|
* mm_tlb_flush_pending();
|
|
* ....
|
|
* spin_unlock(&ptl);
|
|
*
|
|
* flush_tlb_range();
|
|
* atomic_dec(&mm->tlb_flush_pending);
|
|
*
|
|
* Where the increment if constrained by the PTL unlock, it thus
|
|
* ensures that the increment is visible if the PTE modification is
|
|
* visible. After all, if there is no PTE modification, nobody cares
|
|
* about TLB flushes either.
|
|
*
|
|
* This very much relies on users (mm_tlb_flush_pending() and
|
|
* mm_tlb_flush_nested()) only caring about _specific_ PTEs (and
|
|
* therefore specific PTLs), because with SPLIT_PTE_PTLOCKS and RCpc
|
|
* locks (PPC) the unlock of one doesn't order against the lock of
|
|
* another PTL.
|
|
*
|
|
* The decrement is ordered by the flush_tlb_range(), such that
|
|
* mm_tlb_flush_pending() will not return false unless all flushes have
|
|
* completed.
|
|
*/
|
|
}
|
|
|
|
static inline void dec_tlb_flush_pending(struct mm_struct *mm)
|
|
{
|
|
/*
|
|
* See inc_tlb_flush_pending().
|
|
*
|
|
* This cannot be smp_mb__before_atomic() because smp_mb() simply does
|
|
* not order against TLB invalidate completion, which is what we need.
|
|
*
|
|
* Therefore we must rely on tlb_flush_*() to guarantee order.
|
|
*/
|
|
atomic_dec(&mm->tlb_flush_pending);
|
|
}
|
|
|
|
static inline bool mm_tlb_flush_pending(struct mm_struct *mm)
|
|
{
|
|
/*
|
|
* Must be called after having acquired the PTL; orders against that
|
|
* PTLs release and therefore ensures that if we observe the modified
|
|
* PTE we must also observe the increment from inc_tlb_flush_pending().
|
|
*
|
|
* That is, it only guarantees to return true if there is a flush
|
|
* pending for _this_ PTL.
|
|
*/
|
|
return atomic_read(&mm->tlb_flush_pending);
|
|
}
|
|
|
|
static inline bool mm_tlb_flush_nested(struct mm_struct *mm)
|
|
{
|
|
/*
|
|
* Similar to mm_tlb_flush_pending(), we must have acquired the PTL
|
|
* for which there is a TLB flush pending in order to guarantee
|
|
* we've seen both that PTE modification and the increment.
|
|
*
|
|
* (no requirement on actually still holding the PTL, that is irrelevant)
|
|
*/
|
|
return atomic_read(&mm->tlb_flush_pending) > 1;
|
|
}
|
|
|
|
struct vm_fault;
|
|
|
|
struct vm_special_mapping {
|
|
const char *name; /* The name, e.g. "[vdso]". */
|
|
|
|
/*
|
|
* If .fault is not provided, this points to a
|
|
* NULL-terminated array of pages that back the special mapping.
|
|
*
|
|
* This must not be NULL unless .fault is provided.
|
|
*/
|
|
struct page **pages;
|
|
|
|
/*
|
|
* If non-NULL, then this is called to resolve page faults
|
|
* on the special mapping. If used, .pages is not checked.
|
|
*/
|
|
int (*fault)(const struct vm_special_mapping *sm,
|
|
struct vm_area_struct *vma,
|
|
struct vm_fault *vmf);
|
|
|
|
int (*mremap)(const struct vm_special_mapping *sm,
|
|
struct vm_area_struct *new_vma);
|
|
};
|
|
|
|
enum tlb_flush_reason {
|
|
TLB_FLUSH_ON_TASK_SWITCH,
|
|
TLB_REMOTE_SHOOTDOWN,
|
|
TLB_LOCAL_SHOOTDOWN,
|
|
TLB_LOCAL_MM_SHOOTDOWN,
|
|
TLB_REMOTE_SEND_IPI,
|
|
NR_TLB_FLUSH_REASONS,
|
|
};
|
|
|
|
/*
|
|
* A swap entry has to fit into a "unsigned long", as the entry is hidden
|
|
* in the "index" field of the swapper address space.
|
|
*/
|
|
typedef struct {
|
|
unsigned long val;
|
|
} swp_entry_t;
|
|
|
|
#endif /* _LINUX_MM_TYPES_H */
|