WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-changelog

[Xen-changelog] Add hook in get_user_pages to allow lookups of foreign m

To: xen-changelog@xxxxxxxxxxxxxxxxxxx
Subject: [Xen-changelog] Add hook in get_user_pages to allow lookups of foreign mapped pages.
From: Xen patchbot -unstable <patchbot-unstable@xxxxxxxxxxxxxxxxxxx>
Date: Mon, 04 Jul 2005 11:36:11 -0400
Delivery-date: Mon, 04 Jul 2005 15:36:39 +0000
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
List-help: <mailto:xen-changelog-request@lists.xensource.com?subject=help>
List-id: BK change log <xen-changelog.lists.xensource.com>
List-post: <mailto:xen-changelog@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-changelog>, <mailto:xen-changelog-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-changelog>, <mailto:xen-changelog-request@lists.xensource.com?subject=unsubscribe>
Reply-to: xen-devel@xxxxxxxxxxxxxxxxxxx
Sender: xen-changelog-bounces@xxxxxxxxxxxxxxxxxxx
# HG changeset patch
# User akw27@xxxxxxxxxxxxxxxxxxxxxx
# Node ID f6e7c967212e5c0098e6f6cdbc9cdac042d9124c
# Parent  f8acd354e1295226fbda14aaf8bd164e07b93742

Add hook in get_user_pages to allow lookups of foreign mapped pages.

Direct IO to userspace (e.g. with libaio) needs to map user virtual addresses
down to page structs.  This patch adds a new vma flag (VM_FOREIGN) to tell
get_user_pages that there are foreign frames in the vma.  If VM_FOREIGN is set
vm_private_data points to a map of struct page pointers, indicating the
physical page underpinning the vaddr.

After a fair bit of discussion with Keir, this seems to be the least
intrusive way to allow this sort of lookup.  If this solves things, we
can pull the VM_FOREIGN clause out into make it a noop on non-Xen
arches in the same way that the gate_area check above it is.

diff -r f8acd354e129 -r f6e7c967212e linux-2.6.11-xen-sparse/mm/memory.c
--- a/linux-2.6.11-xen-sparse/mm/memory.c       Sun Jul  3 22:36:48 2005
+++ b/linux-2.6.11-xen-sparse/mm/memory.c       Mon Jul  4 15:31:47 2005
@@ -907,6 +907,24 @@
                        continue;
                }
 
+                if (vma && (vma->vm_flags & VM_FOREIGN))
+                {
+                    struct page **map = vma->vm_private_data;
+                    int offset = (start - vma->vm_start) >> PAGE_SHIFT;
+
+                    if (map[offset] != NULL) {
+                        if (pages) {
+                            pages[i] = map[offset];
+                        } 
+                        if (vmas) 
+                            vmas[i] = vma;
+                        i++;
+                        start += PAGE_SIZE;
+                        len--;
+                        continue;
+                    }
+                }
+
                if (!vma || (vma->vm_flags & VM_IO)
                                || !(flags & vma->vm_flags))
                        return i ? : -EFAULT;
diff -r f8acd354e129 -r f6e7c967212e linux-2.6.11-xen-sparse/include/linux/mm.h
--- /dev/null   Sun Jul  3 22:36:48 2005
+++ b/linux-2.6.11-xen-sparse/include/linux/mm.h        Mon Jul  4 15:31:47 2005
@@ -0,0 +1,865 @@
+#ifndef _LINUX_MM_H
+#define _LINUX_MM_H
+
+#include <linux/sched.h>
+#include <linux/errno.h>
+
+#ifdef __KERNEL__
+
+#include <linux/config.h>
+#include <linux/gfp.h>
+#include <linux/list.h>
+#include <linux/mmzone.h>
+#include <linux/rbtree.h>
+#include <linux/prio_tree.h>
+#include <linux/fs.h>
+
+struct mempolicy;
+struct anon_vma;
+
+#ifndef CONFIG_DISCONTIGMEM          /* Don't use mapnrs, do it properly */
+extern unsigned long max_mapnr;
+#endif
+
+extern unsigned long num_physpages;
+extern void * high_memory;
+extern unsigned long vmalloc_earlyreserve;
+extern int page_cluster;
+
+#ifdef CONFIG_SYSCTL
+extern int sysctl_legacy_va_layout;
+#else
+#define sysctl_legacy_va_layout 0
+#endif
+
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/processor.h>
+#include <asm/atomic.h>
+
+#ifndef MM_VM_SIZE
+#define MM_VM_SIZE(mm) ((TASK_SIZE + PGDIR_SIZE - 1) & PGDIR_MASK)
+#endif
+
+#define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n))
+
+/*
+ * Linux kernel virtual memory manager primitives.
+ * The idea being to have a "virtual" mm in the same way
+ * we have a virtual fs - giving a cleaner interface to the
+ * mm details, and allowing different kinds of memory mappings
+ * (from shared memory to executable loading to arbitrary
+ * mmap() functions).
+ */
+
+/*
+ * This struct defines a memory VMM memory area. There is one of these
+ * per VM-area/task.  A VM area is any part of the process virtual memory
+ * space that has a special rule for the page-fault handlers (ie a shared
+ * library, the executable area etc).
+ */
+struct vm_area_struct {
+       struct mm_struct * vm_mm;       /* The address space we belong to. */
+       unsigned long vm_start;         /* Our start address within vm_mm. */
+       unsigned long vm_end;           /* The first byte after our end address
+                                          within vm_mm. */
+
+       /* linked list of VM areas per task, sorted by address */
+       struct vm_area_struct *vm_next;
+
+       pgprot_t vm_page_prot;          /* Access permissions of this VMA. */
+       unsigned long vm_flags;         /* Flags, listed below. */
+
+       struct rb_node vm_rb;
+
+       /*
+        * For areas with an address space and backing store,
+        * linkage into the address_space->i_mmap prio tree, or
+        * linkage to the list of like vmas hanging off its node, or
+        * linkage of vma in the address_space->i_mmap_nonlinear list.
+        */
+       union {
+               struct {
+                       struct list_head list;
+                       void *parent;   /* aligns with prio_tree_node parent */
+                       struct vm_area_struct *head;
+               } vm_set;
+
+               struct raw_prio_tree_node prio_tree_node;
+       } shared;
+
+       /*
+        * A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma
+        * list, after a COW of one of the file pages.  A MAP_SHARED vma
+        * can only be in the i_mmap tree.  An anonymous MAP_PRIVATE, stack
+        * or brk vma (with NULL file) can only be in an anon_vma list.
+        */
+       struct list_head anon_vma_node; /* Serialized by anon_vma->lock */
+       struct anon_vma *anon_vma;      /* Serialized by page_table_lock */
+
+       /* Function pointers to deal with this struct. */
+       struct vm_operations_struct * vm_ops;
+
+       /* Information about our backing store: */
+       unsigned long vm_pgoff;         /* Offset (within vm_file) in PAGE_SIZE
+                                          units, *not* PAGE_CACHE_SIZE */
+       struct file * vm_file;          /* File we map to (can be NULL). */
+       void * vm_private_data;         /* was vm_pte (shared mem) */
+       unsigned long vm_truncate_count;/* truncate_count or restart_addr */
+
+#ifndef CONFIG_MMU
+       atomic_t vm_usage;              /* refcount (VMAs shared if !MMU) */
+#endif
+#ifdef CONFIG_NUMA
+       struct mempolicy *vm_policy;    /* NUMA policy for the VMA */
+#endif
+};
+
+/*
+ * This struct defines the per-mm list of VMAs for uClinux. If CONFIG_MMU is
+ * disabled, then there's a single shared list of VMAs maintained by the
+ * system, and mm's subscribe to these individually
+ */
+struct vm_list_struct {
+       struct vm_list_struct   *next;
+       struct vm_area_struct   *vma;
+};
+
+#ifndef CONFIG_MMU
+extern struct rb_root nommu_vma_tree;
+extern struct rw_semaphore nommu_vma_sem;
+
+extern unsigned int kobjsize(const void *objp);
+#endif
+
+/*
+ * vm_flags..
+ */
+#define VM_READ                0x00000001      /* currently active flags */
+#define VM_WRITE       0x00000002
+#define VM_EXEC                0x00000004
+#define VM_SHARED      0x00000008
+
+#define VM_MAYREAD     0x00000010      /* limits for mprotect() etc */
+#define VM_MAYWRITE    0x00000020
+#define VM_MAYEXEC     0x00000040
+#define VM_MAYSHARE    0x00000080
+
+#define VM_GROWSDOWN   0x00000100      /* general info on the segment */
+#define VM_GROWSUP     0x00000200
+#define VM_SHM         0x00000400      /* shared memory area, don't swap out */
+#define VM_DENYWRITE   0x00000800      /* ETXTBSY on write attempts.. */
+
+#define VM_EXECUTABLE  0x00001000
+#define VM_LOCKED      0x00002000
+#define VM_IO           0x00004000     /* Memory mapped I/O or similar */
+
+                                       /* Used by sys_madvise() */
+#define VM_SEQ_READ    0x00008000      /* App will access data sequentially */
+#define VM_RAND_READ   0x00010000      /* App will not benefit from clustered 
reads */
+
+#define VM_DONTCOPY    0x00020000      /* Do not copy this vma on fork */
+#define VM_DONTEXPAND  0x00040000      /* Cannot expand with mremap() */
+#define VM_RESERVED    0x00080000      /* Don't unmap it from swap_out */
+#define VM_ACCOUNT     0x00100000      /* Is a VM accounted object */
+#define VM_HUGETLB     0x00400000      /* Huge TLB Page VM */
+#define VM_NONLINEAR   0x00800000      /* Is non-linear (remap_file_pages) */
+#define VM_FOREIGN      0x01000000      /* Has pages belonging to another VM */
+
+#ifndef VM_STACK_DEFAULT_FLAGS         /* arch can override this */
+#define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS
+#endif
+
+#ifdef CONFIG_STACK_GROWSUP
+#define VM_STACK_FLAGS (VM_GROWSUP | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT)
+#else
+#define VM_STACK_FLAGS (VM_GROWSDOWN | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT)
+#endif
+
+#define VM_READHINTMASK                        (VM_SEQ_READ | VM_RAND_READ)
+#define VM_ClearReadHint(v)            (v)->vm_flags &= ~VM_READHINTMASK
+#define VM_NormalReadHint(v)           (!((v)->vm_flags & VM_READHINTMASK))
+#define VM_SequentialReadHint(v)       ((v)->vm_flags & VM_SEQ_READ)
+#define VM_RandomReadHint(v)           ((v)->vm_flags & VM_RAND_READ)
+
+/*
+ * mapping from the currently active vm_flags protection bits (the
+ * low four bits) to a page protection mask..
+ */
+extern pgprot_t protection_map[16];
+
+
+/*
+ * These are the virtual MM functions - opening of an area, closing and
+ * unmapping it (needed to keep files on disk up-to-date etc), pointer
+ * to the functions called when a no-page or a wp-page exception occurs. 
+ */
+struct vm_operations_struct {
+       void (*open)(struct vm_area_struct * area);
+       void (*close)(struct vm_area_struct * area);
+       struct page * (*nopage)(struct vm_area_struct * area, unsigned long 
address, int *type);
+       int (*populate)(struct vm_area_struct * area, unsigned long address, 
unsigned long len, pgprot_t prot, unsigned long pgoff, int nonblock);
+#ifdef CONFIG_NUMA
+       int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new);
+       struct mempolicy *(*get_policy)(struct vm_area_struct *vma,
+                                       unsigned long addr);
+#endif
+};
+
+struct mmu_gather;
+struct inode;
+
+#ifdef ARCH_HAS_ATOMIC_UNSIGNED
+typedef unsigned page_flags_t;
+#else
+typedef unsigned long page_flags_t;
+#endif
+
+/*
+ * Each physical page in the system has a struct page associated with
+ * it to keep track of whatever it is we are using the page for at the
+ * moment. Note that we have no way to track which tasks are using
+ * a page.
+ */
+struct page {
+       page_flags_t flags;             /* Atomic flags, some possibly
+                                        * updated asynchronously */
+       atomic_t _count;                /* Usage count, see below. */
+       atomic_t _mapcount;             /* Count of ptes mapped in mms,
+                                        * to show when page is mapped
+                                        * & limit reverse map searches.
+                                        */
+       unsigned long private;          /* Mapping-private opaque data:
+                                        * usually used for buffer_heads
+                                        * if PagePrivate set; used for
+                                        * swp_entry_t if PageSwapCache
+                                        * When page is free, this indicates
+                                        * order in the buddy system.
+                                        */
+       struct address_space *mapping;  /* If low bit clear, points to
+                                        * inode address_space, or NULL.
+                                        * If page mapped as anonymous
+                                        * memory, low bit is set, and
+                                        * it points to anon_vma object:
+                                        * see PAGE_MAPPING_ANON below.
+                                        */
+       pgoff_t index;                  /* Our offset within mapping. */
+       struct list_head lru;           /* Pageout list, eg. active_list
+                                        * protected by zone->lru_lock !
+                                        */
+       /*
+        * On machines where all RAM is mapped into kernel address space,
+        * we can simply calculate the virtual address. On machines with
+        * highmem some memory is mapped into kernel virtual memory
+        * dynamically, so we need a place to store that address.
+        * Note that this field could be 16 bits on x86 ... ;)
+        *
+        * Architectures with slow multiplication can define
+        * WANT_PAGE_VIRTUAL in asm/page.h
+        */
+#if defined(WANT_PAGE_VIRTUAL)
+       void *virtual;                  /* Kernel virtual address (NULL if
+                                          not kmapped, ie. highmem) */
+#endif /* WANT_PAGE_VIRTUAL */
+};
+
+/*
+ * FIXME: take this include out, include page-flags.h in
+ * files which need it (119 of them)
+ */
+#include <linux/page-flags.h>
+
+/*
+ * Methods to modify the page usage count.
+ *
+ * What counts for a page usage:
+ * - cache mapping   (page->mapping)
+ * - private data    (page->private)
+ * - page mapped in a task's page tables, each mapping
+ *   is counted separately
+ *
+ * Also, many kernel routines increase the page count before a critical
+ * routine so they can be sure the page doesn't go away from under them.
+ *
+ * Since 2.6.6 (approx), a free page has ->_count = -1.  This is so that we
+ * can use atomic_add_negative(-1, page->_count) to detect when the page
+ * becomes free and so that we can also use atomic_inc_and_test to atomically
+ * detect when we just tried to grab a ref on a page which some other CPU has
+ * already deemed to be freeable.
+ *
+ * NO code should make assumptions about this internal detail!  Use the 
provided
+ * macros which retain the old rules: page_count(page) == 0 is a free page.
+ */
+
+/*
+ * Drop a ref, return true if the logical refcount fell to zero (the page has
+ * no users)
+ */
+#define put_page_testzero(p)                           \
+       ({                                              \
+               BUG_ON(page_count(p) == 0);             \
+               atomic_add_negative(-1, &(p)->_count);  \
+       })
+
+/*
+ * Grab a ref, return true if the page previously had a logical refcount of
+ * zero.  ie: returns true if we just grabbed an already-deemed-to-be-free page
+ */
+#define get_page_testone(p)    atomic_inc_and_test(&(p)->_count)
+
+#define set_page_count(p,v)    atomic_set(&(p)->_count, v - 1)
+#define __put_page(p)          atomic_dec(&(p)->_count)
+
+extern void FASTCALL(__page_cache_release(struct page *));
+
+#ifdef CONFIG_HUGETLB_PAGE
+
+static inline int page_count(struct page *p)
+{
+       if (PageCompound(p))
+               p = (struct page *)p->private;
+       return atomic_read(&(p)->_count) + 1;
+}
+
+static inline void get_page(struct page *page)
+{
+       if (unlikely(PageCompound(page)))
+               page = (struct page *)page->private;
+       atomic_inc(&page->_count);
+}
+
+void put_page(struct page *page);
+
+#else          /* CONFIG_HUGETLB_PAGE */
+
+#define page_count(p)          (atomic_read(&(p)->_count) + 1)
+
+static inline void get_page(struct page *page)
+{
+       atomic_inc(&page->_count);
+}
+
+static inline void put_page(struct page *page)
+{
+       if (!PageReserved(page) && put_page_testzero(page))
+               __page_cache_release(page);
+}
+
+#endif         /* CONFIG_HUGETLB_PAGE */
+
+/*
+ * Multiple processes may "see" the same page. E.g. for untouched
+ * mappings of /dev/null, all processes see the same page full of
+ * zeroes, and text pages of executables and shared libraries have
+ * only one copy in memory, at most, normally.
+ *
+ * For the non-reserved pages, page_count(page) denotes a reference count.
+ *   page_count() == 0 means the page is free.
+ *   page_count() == 1 means the page is used for exactly one purpose
+ *   (e.g. a private data page of one process).
+ *
+ * A page may be used for kmalloc() or anyone else who does a
+ * __get_free_page(). In this case the page_count() is at least 1, and
+ * all other fields are unused but should be 0 or NULL. The
+ * management of this page is the responsibility of the one who uses
+ * it.
+ *
+ * The other pages (we may call them "process pages") are completely
+ * managed by the Linux memory manager: I/O, buffers, swapping etc.
+ * The following discussion applies only to them.
+ *
+ * A page may belong to an inode's memory mapping. In this case,
+ * page->mapping is the pointer to the inode, and page->index is the
+ * file offset of the page, in units of PAGE_CACHE_SIZE.
+ *
+ * A page contains an opaque `private' member, which belongs to the
+ * page's address_space.  Usually, this is the address of a circular
+ * list of the page's disk buffers.
+ *
+ * For pages belonging to inodes, the page_count() is the number of
+ * attaches, plus 1 if `private' contains something, plus one for
+ * the page cache itself.
+ *
+ * All pages belonging to an inode are in these doubly linked lists:
+ * mapping->clean_pages, mapping->dirty_pages and mapping->locked_pages;
+ * using the page->list list_head. These fields are also used for
+ * freelist managemet (when page_count()==0).
+ *
+ * There is also a per-mapping radix tree mapping index to the page
+ * in memory if present. The tree is rooted at mapping->root.  
+ *
+ * All process pages can do I/O:
+ * - inode pages may need to be read from disk,
+ * - inode pages which have been modified and are MAP_SHARED may need
+ *   to be written to disk,
+ * - private pages which have been modified may need to be swapped out
+ *   to swap space and (later) to be read back into memory.
+ */
+
+/*
+ * The zone field is never updated after free_area_init_core()
+ * sets it, so none of the operations on it need to be atomic.
+ * We'll have up to (MAX_NUMNODES * MAX_NR_ZONES) zones total,
+ * so we use (MAX_NODES_SHIFT + MAX_ZONES_SHIFT) here to get enough bits.
+ */
+#define NODEZONE_SHIFT (sizeof(page_flags_t)*8 - MAX_NODES_SHIFT - 
MAX_ZONES_SHIFT)
+#define NODEZONE(node, zone)   ((node << ZONES_SHIFT) | zone)
+
+static inline unsigned long page_zonenum(struct page *page)
+{
+       return (page->flags >> NODEZONE_SHIFT) & (~(~0UL << ZONES_SHIFT));
+}
+static inline unsigned long page_to_nid(struct page *page)
+{
+       return (page->flags >> (NODEZONE_SHIFT + ZONES_SHIFT));
+}
+
+struct zone;
+extern struct zone *zone_table[];
+
+static inline struct zone *page_zone(struct page *page)
+{
+       return zone_table[page->flags >> NODEZONE_SHIFT];
+}
+
+static inline void set_page_zone(struct page *page, unsigned long nodezone_num)
+{
+       page->flags &= ~(~0UL << NODEZONE_SHIFT);
+       page->flags |= nodezone_num << NODEZONE_SHIFT;
+}
+
+#ifndef CONFIG_DISCONTIGMEM
+/* The array of struct pages - for discontigmem use pgdat->lmem_map */
+extern struct page *mem_map;
+#endif
+
+static inline void *lowmem_page_address(struct page *page)
+{
+       return __va(page_to_pfn(page) << PAGE_SHIFT);
+}
+
+#if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL)
+#define HASHED_PAGE_VIRTUAL
+#endif
+
+#if defined(WANT_PAGE_VIRTUAL)
+#define page_address(page) ((page)->virtual)
+#define set_page_address(page, address)                        \
+       do {                                            \
+               (page)->virtual = (address);            \
+       } while(0)
+#define page_address_init()  do { } while(0)
+#endif
+
+#if defined(HASHED_PAGE_VIRTUAL)
+void *page_address(struct page *page);
+void set_page_address(struct page *page, void *virtual);
+void page_address_init(void);
+#endif
+
+#if !defined(HASHED_PAGE_VIRTUAL) && !defined(WANT_PAGE_VIRTUAL)
+#define page_address(page) lowmem_page_address(page)
+#define set_page_address(page, address)  do { } while(0)
+#define page_address_init()  do { } while(0)
+#endif
+
+/*
+ * On an anonymous page mapped into a user virtual memory area,
+ * page->mapping points to its anon_vma, not to a struct address_space;
+ * with the PAGE_MAPPING_ANON bit set to distinguish it.
+ *
+ * Please note that, confusingly, "page_mapping" refers to the inode
+ * address_space which maps the page from disk; whereas "page_mapped"
+ * refers to user virtual address space into which the page is mapped.
+ */
+#define PAGE_MAPPING_ANON      1
+
+extern struct address_space swapper_space;
+static inline struct address_space *page_mapping(struct page *page)
+{
+       struct address_space *mapping = page->mapping;
+
+       if (unlikely(PageSwapCache(page)))
+               mapping = &swapper_space;
+       else if (unlikely((unsigned long)mapping & PAGE_MAPPING_ANON))
+               mapping = NULL;
+       return mapping;
+}
+
+static inline int PageAnon(struct page *page)
+{
+       return ((unsigned long)page->mapping & PAGE_MAPPING_ANON) != 0;
+}
+
+/*
+ * Return the pagecache index of the passed page.  Regular pagecache pages
+ * use ->index whereas swapcache pages use ->private
+ */
+static inline pgoff_t page_index(struct page *page)
+{
+       if (unlikely(PageSwapCache(page)))
+               return page->private;
+       return page->index;
+}
+
+/*
+ * The atomic page->_mapcount, like _count, starts from -1:
+ * so that transitions both from it and to it can be tracked,
+ * using atomic_inc_and_test and atomic_add_negative(-1).
+ */
+static inline void reset_page_mapcount(struct page *page)
+{
+       atomic_set(&(page)->_mapcount, -1);
+}
+
+static inline int page_mapcount(struct page *page)
+{
+       return atomic_read(&(page)->_mapcount) + 1;
+}
+
+/*
+ * Return true if this page is mapped into pagetables.
+ */
+static inline int page_mapped(struct page *page)
+{
+       return atomic_read(&(page)->_mapcount) >= 0;
+}
+
+/*
+ * Error return values for the *_nopage functions
+ */
+#define NOPAGE_SIGBUS  (NULL)
+#define NOPAGE_OOM     ((struct page *) (-1))
+
+/*
+ * Different kinds of faults, as returned by handle_mm_fault().
+ * Used to decide whether a process gets delivered SIGBUS or
+ * just gets major/minor fault counters bumped up.
+ */
+#define VM_FAULT_OOM   (-1)
+#define VM_FAULT_SIGBUS        0
+#define VM_FAULT_MINOR 1
+#define VM_FAULT_MAJOR 2
+
+#define offset_in_page(p)      ((unsigned long)(p) & ~PAGE_MASK)
+
+extern void show_free_areas(void);
+
+#ifdef CONFIG_SHMEM
+struct page *shmem_nopage(struct vm_area_struct *vma,
+                       unsigned long address, int *type);
+int shmem_set_policy(struct vm_area_struct *vma, struct mempolicy *new);
+struct mempolicy *shmem_get_policy(struct vm_area_struct *vma,
+                                       unsigned long addr);
+int shmem_lock(struct file *file, int lock, struct user_struct *user);
+#else
+#define shmem_nopage filemap_nopage
+#define shmem_lock(a, b, c)    ({0;})  /* always in memory, no need to lock */
+#define shmem_set_policy(a, b) (0)
+#define shmem_get_policy(a, b) (NULL)
+#endif
+struct file *shmem_file_setup(char *name, loff_t size, unsigned long flags);
+
+int shmem_zero_setup(struct vm_area_struct *);
+
+static inline int can_do_mlock(void)
+{
+       if (capable(CAP_IPC_LOCK))
+               return 1;
+       if (current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur != 0)
+               return 1;
+       return 0;
+}
+extern int user_shm_lock(size_t, struct user_struct *);
+extern void user_shm_unlock(size_t, struct user_struct *);
+
+/*
+ * Parameter block passed down to zap_pte_range in exceptional cases.
+ */
+struct zap_details {
+       struct vm_area_struct *nonlinear_vma;   /* Check page->index if set */
+       struct address_space *check_mapping;    /* Check page->mapping if set */
+       pgoff_t first_index;                    /* Lowest page->index to unmap 
*/
+       pgoff_t last_index;                     /* Highest page->index to unmap 
*/
+       spinlock_t *i_mmap_lock;                /* For unmap_mapping_range: */
+       unsigned long break_addr;               /* Where unmap_vmas stopped */
+       unsigned long truncate_count;           /* Compare vm_truncate_count */
+};
+
+void zap_page_range(struct vm_area_struct *vma, unsigned long address,
+               unsigned long size, struct zap_details *);
+int unmap_vmas(struct mmu_gather **tlbp, struct mm_struct *mm,
+               struct vm_area_struct *start_vma, unsigned long start_addr,
+               unsigned long end_addr, unsigned long *nr_accounted,
+               struct zap_details *);
+void clear_page_range(struct mmu_gather *tlb, unsigned long addr, unsigned 
long end);
+int copy_page_range(struct mm_struct *dst, struct mm_struct *src,
+                       struct vm_area_struct *vma);
+int zeromap_page_range(struct vm_area_struct *vma, unsigned long from,
+                       unsigned long size, pgprot_t prot);
+void unmap_mapping_range(struct address_space *mapping,
+               loff_t const holebegin, loff_t const holelen, int even_cows);
+
+static inline void unmap_shared_mapping_range(struct address_space *mapping,
+               loff_t const holebegin, loff_t const holelen)
+{
+       unmap_mapping_range(mapping, holebegin, holelen, 0);
+}
+
+extern int vmtruncate(struct inode * inode, loff_t offset);
+extern pud_t *FASTCALL(__pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned 
long address));
+extern pmd_t *FASTCALL(__pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned 
long address));
+extern pte_t *FASTCALL(pte_alloc_kernel(struct mm_struct *mm, pmd_t *pmd, 
unsigned long address));
+extern pte_t *FASTCALL(pte_alloc_map(struct mm_struct *mm, pmd_t *pmd, 
unsigned long address));
+extern int install_page(struct mm_struct *mm, struct vm_area_struct *vma, 
unsigned long addr, struct page *page, pgprot_t prot);
+extern int install_file_pte(struct mm_struct *mm, struct vm_area_struct *vma, 
unsigned long addr, unsigned long pgoff, pgprot_t prot);
+extern int handle_mm_fault(struct mm_struct *mm,struct vm_area_struct *vma, 
unsigned long address, int write_access);
+extern int make_pages_present(unsigned long addr, unsigned long end);
+extern int access_process_vm(struct task_struct *tsk, unsigned long addr, void 
*buf, int len, int write);
+void install_arg_page(struct vm_area_struct *, struct page *, unsigned long);
+
+int get_user_pages(struct task_struct *tsk, struct mm_struct *mm, unsigned 
long start,
+               int len, int write, int force, struct page **pages, struct 
vm_area_struct **vmas);
+
+int __set_page_dirty_buffers(struct page *page);
+int __set_page_dirty_nobuffers(struct page *page);
+int redirty_page_for_writepage(struct writeback_control *wbc,
+                               struct page *page);
+int FASTCALL(set_page_dirty(struct page *page));
+int set_page_dirty_lock(struct page *page);
+int clear_page_dirty_for_io(struct page *page);
+
+extern unsigned long do_mremap(unsigned long addr,
+                              unsigned long old_len, unsigned long new_len,
+                              unsigned long flags, unsigned long new_addr);
+
+/*
+ * Prototype to add a shrinker callback for ageable caches.
+ * 
+ * These functions are passed a count `nr_to_scan' and a gfpmask.  They should
+ * scan `nr_to_scan' objects, attempting to free them.
+ *
+ * The callback must the number of objects which remain in the cache.
+ *
+ * The callback will be passes nr_to_scan == 0 when the VM is querying the
+ * cache size, so a fastpath for that case is appropriate.
+ */
+typedef int (*shrinker_t)(int nr_to_scan, unsigned int gfp_mask);
+
+/*
+ * Add an aging callback.  The int is the number of 'seeks' it takes
+ * to recreate one of the objects that these functions age.
+ */
+
+#define DEFAULT_SEEKS 2
+struct shrinker;
+extern struct shrinker *set_shrinker(int, shrinker_t);
+extern void remove_shrinker(struct shrinker *shrinker);
+
+/*
+ * On a two-level or three-level page table, this ends up being trivial. Thus
+ * the inlining and the symmetry break with pte_alloc_map() that does all
+ * of this out-of-line.
+ */
+/*
+ * The following ifdef needed to get the 4level-fixup.h header to work.
+ * Remove it when 4level-fixup.h has been removed.
+ */
+#ifdef CONFIG_MMU
+#ifndef __ARCH_HAS_4LEVEL_HACK 
+static inline pud_t *pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long 
address)
+{
+       if (pgd_none(*pgd))
+               return __pud_alloc(mm, pgd, address);
+       return pud_offset(pgd, address);
+}
+
+static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long 
address)
+{
+       if (pud_none(*pud))
+               return __pmd_alloc(mm, pud, address);
+       return pmd_offset(pud, address);
+}
+#endif
+#endif /* CONFIG_MMU */
+
+extern void free_area_init(unsigned long * zones_size);
+extern void free_area_init_node(int nid, pg_data_t *pgdat,
+       unsigned long * zones_size, unsigned long zone_start_pfn, 
+       unsigned long *zholes_size);
+extern void memmap_init_zone(unsigned long, int, unsigned long, unsigned long);
+extern void mem_init(void);
+extern void show_mem(void);
+extern void si_meminfo(struct sysinfo * val);
+extern void si_meminfo_node(struct sysinfo *val, int nid);
+
+/* prio_tree.c */
+void vma_prio_tree_add(struct vm_area_struct *, struct vm_area_struct *old);
+void vma_prio_tree_insert(struct vm_area_struct *, struct prio_tree_root *);
+void vma_prio_tree_remove(struct vm_area_struct *, struct prio_tree_root *);
+struct vm_area_struct *vma_prio_tree_next(struct vm_area_struct *vma,
+       struct prio_tree_iter *iter);
+
+#define vma_prio_tree_foreach(vma, iter, root, begin, end)     \
+       for (prio_tree_iter_init(iter, root, begin, end), vma = NULL;   \
+               (vma = vma_prio_tree_next(vma, iter)); )
+
+static inline void vma_nonlinear_insert(struct vm_area_struct *vma,
+                                       struct list_head *list)
+{
+       vma->shared.vm_set.parent = NULL;
+       list_add_tail(&vma->shared.vm_set.list, list);
+}
+
+/* mmap.c */
+extern int __vm_enough_memory(long pages, int cap_sys_admin);
+extern void vma_adjust(struct vm_area_struct *vma, unsigned long start,
+       unsigned long end, pgoff_t pgoff, struct vm_area_struct *insert);
+extern struct vm_area_struct *vma_merge(struct mm_struct *,
+       struct vm_area_struct *prev, unsigned long addr, unsigned long end,
+       unsigned long vm_flags, struct anon_vma *, struct file *, pgoff_t,
+       struct mempolicy *);
+extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *);
+extern int split_vma(struct mm_struct *,
+       struct vm_area_struct *, unsigned long addr, int new_below);
+extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
+extern void __vma_link_rb(struct mm_struct *, struct vm_area_struct *,
+       struct rb_node **, struct rb_node *);
+extern struct vm_area_struct *copy_vma(struct vm_area_struct **,
+       unsigned long addr, unsigned long len, pgoff_t pgoff);
+extern void exit_mmap(struct mm_struct *);
+
+extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned 
long, unsigned long, unsigned long);
+
+extern unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
+       unsigned long len, unsigned long prot,
+       unsigned long flag, unsigned long pgoff);
+
+static inline unsigned long do_mmap(struct file *file, unsigned long addr,
+       unsigned long len, unsigned long prot,
+       unsigned long flag, unsigned long offset)
+{
+       unsigned long ret = -EINVAL;
+       if ((offset + PAGE_ALIGN(len)) < offset)
+               goto out;
+       if (!(offset & ~PAGE_MASK))
+               ret = do_mmap_pgoff(file, addr, len, prot, flag, offset >> 
PAGE_SHIFT);
+out:
+       return ret;
+}
+
+extern int do_munmap(struct mm_struct *, unsigned long, size_t);
+
+extern unsigned long do_brk(unsigned long, unsigned long);
+
+/* filemap.c */
+extern unsigned long page_unuse(struct page *);
+extern void truncate_inode_pages(struct address_space *, loff_t);
+
+/* generic vm_area_ops exported for stackable file systems */
+extern struct page *filemap_nopage(struct vm_area_struct *, unsigned long, int 
*);
+extern int filemap_populate(struct vm_area_struct *, unsigned long,
+               unsigned long, pgprot_t, unsigned long, int);
+
+/* mm/page-writeback.c */
+int write_one_page(struct page *page, int wait);
+
+/* readahead.c */
+#define VM_MAX_READAHEAD       128     /* kbytes */
+#define VM_MIN_READAHEAD       16      /* kbytes (includes current page) */
+#define VM_MAX_CACHE_HIT       256     /* max pages in a row in cache before
+                                        * turning readahead off */
+
+int do_page_cache_readahead(struct address_space *mapping, struct file *filp,
+                       unsigned long offset, unsigned long nr_to_read);
+int force_page_cache_readahead(struct address_space *mapping, struct file 
*filp,
+                       unsigned long offset, unsigned long nr_to_read);
+unsigned long  page_cache_readahead(struct address_space *mapping,
+                         struct file_ra_state *ra,
+                         struct file *filp,
+                         unsigned long offset,
+                         unsigned long size);
+void handle_ra_miss(struct address_space *mapping, 
+                   struct file_ra_state *ra, pgoff_t offset);
+unsigned long max_sane_readahead(unsigned long nr);
+
+/* Do stack extension */
+extern int expand_stack(struct vm_area_struct * vma, unsigned long address);
+
+/* Look up the first VMA which satisfies  addr < vm_end,  NULL if none. */
+extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long 
addr);
+extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned 
long addr,
+                                            struct vm_area_struct **pprev);
+
+/* Look up the first VMA which intersects the interval start_addr..end_addr-1,
+   NULL if none.  Assume start_addr < end_addr. */
+static inline struct vm_area_struct * find_vma_intersection(struct mm_struct * 
mm, unsigned long start_addr, unsigned long end_addr)
+{
+       struct vm_area_struct * vma = find_vma(mm,start_addr);
+
+       if (vma && end_addr <= vma->vm_start)
+               vma = NULL;
+       return vma;
+}
+
+static inline unsigned long vma_pages(struct vm_area_struct *vma)
+{
+       return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+}
+
+extern struct vm_area_struct *find_extend_vma(struct mm_struct *mm, unsigned 
long addr);
+
+extern struct page * vmalloc_to_page(void *addr);
+extern unsigned long vmalloc_to_pfn(void *addr);
+extern struct page * follow_page(struct mm_struct *mm, unsigned long address,
+               int write);
+extern int check_user_page_readable(struct mm_struct *mm, unsigned long 
address);
+int remap_pfn_range(struct vm_area_struct *, unsigned long,
+               unsigned long, unsigned long, pgprot_t);
+/* Allow arch override for mapping of device and I/O (non-RAM) pages. */
+#ifndef io_remap_pfn_range
+#define io_remap_pfn_range remap_pfn_range
+#endif
+
+#ifdef CONFIG_PROC_FS
+void __vm_stat_account(struct mm_struct *, unsigned long, struct file *, long);
+#else
+static inline void __vm_stat_account(struct mm_struct *mm,
+                       unsigned long flags, struct file *file, long pages)
+{
+}
+#endif /* CONFIG_PROC_FS */
+
+static inline void vm_stat_account(struct vm_area_struct *vma)
+{
+       __vm_stat_account(vma->vm_mm, vma->vm_flags, vma->vm_file,
+                                                       vma_pages(vma));
+}
+
+static inline void vm_stat_unaccount(struct vm_area_struct *vma)
+{
+       __vm_stat_account(vma->vm_mm, vma->vm_flags, vma->vm_file,
+                                                       -vma_pages(vma));
+}
+
+/* update per process rss and vm hiwater data */
+extern void update_mem_hiwater(void);
+
+#ifndef CONFIG_DEBUG_PAGEALLOC
+static inline void
+kernel_map_pages(struct page *page, int numpages, int enable)
+{
+}
+#endif
+
+extern struct vm_area_struct *get_gate_vma(struct task_struct *tsk);
+#ifdef __HAVE_ARCH_GATE_AREA
+int in_gate_area_no_task(unsigned long addr);
+int in_gate_area(struct task_struct *task, unsigned long addr);
+#else
+int in_gate_area_no_task(unsigned long addr);
+#define in_gate_area(task, addr) ({(void)task; in_gate_area_no_task(addr);})
+#endif /* __HAVE_ARCH_GATE_AREA */
+
+#endif /* __KERNEL__ */
+#endif /* _LINUX_MM_H */

_______________________________________________
Xen-changelog mailing list
Xen-changelog@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-changelog

<Prev in Thread] Current Thread [Next in Thread>
  • [Xen-changelog] Add hook in get_user_pages to allow lookups of foreign mapped pages., Xen patchbot -unstable <=