litmus-rt.git - The LITMUS^RT kernel.

diff options

author	Christoph Lameter <clameter@sgi.com>	2007-02-20 16:57:51 -0500
committer	Linus Torvalds <torvalds@woody.linux-foundation.org>	2007-02-20 20:10:13 -0500
commit	53b8a315b76a3f3c70a5644976c0095460eb13d8 (patch)
tree	f407a607adb1f552942aef9150ec709ed3f01798
parent	74c7aa8b8581e0ba8d6d17c623b9279aaabbb0cf (diff)

[PATCH] Convert highest_possible_processor_id to nr_cpu_ids

We frequently need the maximum number of possible processors in order to allocate arrays for all processors. So far this was done using highest_possible_processor_id(). However, we do need the number of processors not the highest id. Moreover the number was so far dynamically calculated on each invokation. The number of possible processors does not change when the system is running. We can therefore calculate that number once. Signed-off-by: Christoph Lameter <clameter@sgi.com> Cc: Frederik Deweerdt <frederik.deweerdt@gmail.com> Cc: Neil Brown <neilb@suse.de> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Diffstat

-rw-r--r--

include/linux/cpumask.h

-rw-r--r--

init/main.c

-rw-r--r--

lib/cpumask.c

-rw-r--r--

net/bridge/netfilter/ebtables.c

-rw-r--r--

net/sunrpc/svc.c

5 files changed, 17 insertions, 29 deletions

 #endif
 #ifdef CONFIG_SMP
-int highest_possible_processor_id(void);
+extern int nr_cpu_ids;
 #define any_online_cpu(mask) __any_online_cpu(&(mask))
 int __any_online_cpu(const cpumask_t *mask);
 #else
-#define highest_possible_processor_id() 0
+#define nr_cpu_ids                      1
 #define any_online_cpu(mask)            0
 #endif
 /* Called by boot processor to activate the rest. */
 static void __init smp_init(void)
 {
-        unsigned int i;
+        unsigned int cpu;
+        unsigned highest = 0;
+        for_each_cpu_mask(cpu, cpu_possible_map)
+                highest = cpu;
+        nr_cpu_ids = highest + 1;
         /* FIXME: This should be done in userspace --RR */
-        for_each_present_cpu(i) {
+        for_each_present_cpu(cpu) {
                 if (num_online_cpus() >= max_cpus)
                         break;
-                if (!cpu_online(i))
+                if (!cpu_online(cpu))
-                        cpu_up(i);
+                        cpu_up(cpu);
         }
         /* Any cleanup work */
 }
 EXPORT_SYMBOL(__next_cpu);
-/*
+int nr_cpu_ids;
- * Find the highest possible smp_processor_id()
+EXPORT_SYMBOL(nr_cpu_ids);
- *
- * Note: if we're prepared to assume that cpu_possible_map never changes
- * (reasonable) then this function should cache its return value.
- */
-int highest_possible_processor_id(void)
-{
-        unsigned int cpu;
-        unsigned highest = 0;
-        for_each_cpu_mask(cpu, cpu_possible_map)
-                highest = cpu;
-        return highest;
-}
-EXPORT_SYMBOL(highest_possible_processor_id);
 int __any_online_cpu(const cpumask_t *mask)
 {
                 /* this will get free'd in do_replace()/ebt_register_table()
                    if an error occurs */
                 newinfo->chainstack =
-                        vmalloc((highest_possible_processor_id()+1)
+                        vmalloc(nr_cpu_ids * sizeof(*(newinfo->chainstack)));
-                                        * sizeof(*(newinfo->chainstack)));
                 if (!newinfo->chainstack)
                         return -ENOMEM;
                 for_each_possible_cpu(i) {
         if (tmp.num_counters >= INT_MAX / sizeof(struct ebt_counter))
                 return -ENOMEM;
-        countersize = COUNTER_OFFSET(tmp.nentries) *
+        countersize = COUNTER_OFFSET(tmp.nentries) * nr_cpu_ids;
-                                        (highest_possible_processor_id()+1);
         newinfo = vmalloc(sizeof(*newinfo) + countersize);
         if (!newinfo)
                 return -ENOMEM;
                 return -EINVAL;
         }
-        countersize = COUNTER_OFFSET(repl->nentries) *
+        countersize = COUNTER_OFFSET(repl->nentries) * nr_cpu_ids;
-                                        (highest_possible_processor_id()+1);
         newinfo = vmalloc(sizeof(*newinfo) + countersize);
         ret = -ENOMEM;
         if (!newinfo)
 static int
 svc_pool_map_init_percpu(struct svc_pool_map *m)
 {
-        unsigned int maxpools = highest_possible_processor_id() + 1;
+        unsigned int maxpools = nr_cpu_ids;
         unsigned int pidx = 0;
         unsigned int cpu;
         int err;

// SPDX-License-Identifier: GPL-2.0-only /* * linux/kernel/power/snapshot.c * * This file provides system snapshot/restore functionality for swsusp. * * Copyright (C) 1998-2005 Pavel Machek <pavel@ucw.cz> * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl> */ #define pr_fmt(fmt) "PM: " fmt #include <linux/version.h> #include <linux/module.h> #include <linux/mm.h> #include <linux/suspend.h> #include <linux/delay.h> #include <linux/bitops.h> #include <linux/spinlock.h> #include <linux/kernel.h> #include <linux/pm.h> #include <linux/device.h> #include <linux/init.h> #include <linux/memblock.h> #include <linux/nmi.h> #include <linux/syscalls.h> #include <linux/console.h> #include <linux/highmem.h> #include <linux/list.h> #include <linux/slab.h> #include <linux/compiler.h> #include <linux/ktime.h> #include <linux/set_memory.h> #include <linux/uaccess.h> #include <asm/mmu_context.h> #include <asm/pgtable.h> #include <asm/tlbflush.h> #include <asm/io.h> #include "power.h" #if defined(CONFIG_STRICT_KERNEL_RWX) && defined(CONFIG_ARCH_HAS_SET_MEMORY) static bool hibernate_restore_protection; static bool hibernate_restore_protection_active; void enable_restore_image_protection(void) { hibernate_restore_protection = true; } static inline void hibernate_restore_protection_begin(void) { hibernate_restore_protection_active = hibernate_restore_protection; } static inline void hibernate_restore_protection_end(void) { hibernate_restore_protection_active = false; } static inline void hibernate_restore_protect_page(void *page_address) { if (hibernate_restore_protection_active) set_memory_ro((unsigned long)page_address, 1); } static inline void hibernate_restore_unprotect_page(void *page_address) { if (hibernate_restore_protection_active) set_memory_rw((unsigned long)page_address, 1); } #else static inline void hibernate_restore_protection_begin(void) {} static inline void hibernate_restore_protection_end(void) {} static inline void hibernate_restore_protect_page(void *page_address) {} static inline void hibernate_restore_unprotect_page(void *page_address) {} #endif /* CONFIG_STRICT_KERNEL_RWX && CONFIG_ARCH_HAS_SET_MEMORY */ static int swsusp_page_is_free(struct page *); static void swsusp_set_page_forbidden(struct page *); static void swsusp_unset_page_forbidden(struct page *); /* * Number of bytes to reserve for memory allocations made by device drivers * from their ->freeze() and ->freeze_noirq() callbacks so that they don't * cause image creation to fail (tunable via /sys/power/reserved_size). */ unsigned long reserved_size; void __init hibernate_reserved_size_init(void) { reserved_size = SPARE_PAGES * PAGE_SIZE; } /* * Preferred image size in bytes (tunable via /sys/power/image_size). * When it is set to N, swsusp will do its best to ensure the image * size will not exceed N bytes, but if that is impossible, it will * try to create the smallest image possible. */ unsigned long image_size; void __init hibernate_image_size_init(void) { image_size = ((totalram_pages() * 2) / 5) * PAGE_SIZE; } /* * List of PBEs needed for restoring the pages that were allocated before * the suspend and included in the suspend image, but have also been * allocated by the "resume" kernel, so their contents cannot be written * directly to their "original" page frames. */ struct pbe *restore_pblist; /* struct linked_page is used to build chains of pages */ #define LINKED_PAGE_DATA_SIZE (PAGE_SIZE - sizeof(void *)) struct linked_page { struct linked_page *next; char data[LINKED_PAGE_DATA_SIZE]; } __packed; /* * List of "safe" pages (ie. pages that were not used by the image kernel * before hibernation) that may be used as temporary storage for image kernel * memory contents. */ static struct linked_page *safe_pages_list; /* Pointer to an auxiliary buffer (1 page) */ static void *buffer; #define PG_ANY 0 #define PG_SAFE 1 #define PG_UNSAFE_CLEAR 1 #define PG_UNSAFE_KEEP 0 static unsigned int allocated_unsafe_pages; /** * get_image_page - Allocate a page for a hibernation image. * @gfp_mask: GFP mask for the allocation. * @safe_needed: Get pages that were not used before hibernation (restore only) * * During image restoration, for storing the PBE list and the image data, we can * only use memory pages that do not conflict with the pages used before * hibernation. The "unsafe" pages have PageNosaveFree set and we count them * using allocated_unsafe_pages. * * Each allocated image page is marked as PageNosave and PageNosaveFree so that * swsusp_free() can release it. */ static void *get_image_page(gfp_t gfp_mask, int safe_needed) { void *res; res = (void *)get_zeroed_page(gfp_mask); if (safe_needed) while (res && swsusp_page_is_free(virt_to_page(res))) { /* The page is unsafe, mark it for swsusp_free() */ swsusp_set_page_forbidden(virt_to_page(res)); allocated_unsafe_pages++; res = (void *)get_zeroed_page(gfp_mask); } if (res) { swsusp_set_page_forbidden(virt_to_page(res)); swsusp_set_page_free(virt_to_page(res)); } return res; } static void *__get_safe_page(gfp_t gfp_mask) { if (safe_pages_list) { void *ret = safe_pages_list; safe_pages_list = safe_pages_list->next; memset(ret, 0, PAGE_SIZE); return ret; } return get_image_page(gfp_mask, PG_SAFE); } unsigned long get_safe_page(gfp_t gfp_mask) { return (unsigned long)__get_safe_page(gfp_mask); } static struct page *alloc_image_page(gfp_t gfp_mask) { struct page *page; page = alloc_page(gfp_mask); if (page) { swsusp_set_page_forbidden(page); swsusp_set_page_free(page); } return page; } static void recycle_safe_page(void *page_address) { struct linked_page *lp = page_address; lp->next = safe_pages_list; safe_pages_list = lp; } /** * free_image_page - Free a page allocated for hibernation image. * @addr: Address of the page to free. * @clear_nosave_free: If set, clear the PageNosaveFree bit for the page. * * The page to free should have been allocated by get_image_page() (page flags * set by it are affected). */ static inline void free_image_page(void *addr, int clear_nosave_free) { struct page *page; BUG_ON(!virt_addr_valid(addr)); page = virt_to_page(addr); swsusp_unset_page_forbidden(page); if (clear_nosave_free) swsusp_unset_page_free(page); __free_page(page); } static inline void free_list_of_pages(struct linked_page *list, int clear_page_nosave) { while (list) { struct linked_page *lp = list->next; free_image_page(list, clear_page_nosave); list = lp; } } /* * struct chain_allocator is used for allocating small objects out of * a linked list of pages called 'the chain'. * * The chain grows each time when there is no room for a new object in * the current page. The allocated objects cannot be freed individually. * It is only possible to free them all at once, by freeing the entire * chain. * * NOTE: The chain allocator may be inefficient if the allocated objects * are not much smaller than PAGE_SIZE. */ struct chain_allocator { struct linked_page *chain; /* the chain */ unsigned int used_space; /* total size of objects allocated out of the current page */ gfp_t gfp_mask; /* mask for allocating pages */ int safe_needed; /* if set, only "safe" pages are allocated */ }; static void chain_init(struct chain_allocator *ca, gfp_t gfp_mask, int safe_needed) { ca->chain = NULL; ca->used_space = LINKED_PAGE_DATA_SIZE; ca->gfp_mask = gfp_mask; ca->safe_needed = safe_needed; } static void *chain_alloc(struct chain_allocator *ca, unsigned int size) { void *ret; if (LINKED_PAGE_DATA_SIZE - ca->used_space < size) { struct linked_page *lp; lp = ca->safe_needed ? __get_safe_page(ca->gfp_mask) : get_image_page(ca->gfp_mask, PG_ANY); if (!lp) return NULL; lp->next = ca->chain; ca->chain = lp; ca->used_space = 0; } ret = ca->chain->data + ca->used_space; ca->used_space += size; return ret; } /** * Data types related to memory bitmaps. * * Memory bitmap is a structure consiting of many linked lists of * objects. The main list's elements are of type struct zone_bitmap * and each of them corresonds to one zone. For each zone bitmap * object there is a list of objects of type struct bm_block that * represent each blocks of bitmap in which information is stored. * * struct memory_bitmap contains a pointer to the main list of zone * bitmap objects, a struct bm_position used for browsing the bitmap, * and a pointer to the list of pages used for allocating all of the * zone bitmap objects and bitmap block objects. * * NOTE: It has to be possible to lay out the bitmap in memory * using only allocations of order 0. Additionally, the bitmap is * designed to work with arbitrary number of zones (this is over the * top for now, but let's avoid making unnecessary assumptions ;-). * * struct zone_bitmap contains a pointer to a list of bitmap block * objects and a pointer to the bitmap block object that has been * most recently used for setting bits. Additionally, it contains the * PFNs that correspond to the start and end of the represented zone. * * struct bm_block contains a pointer to the memory page in which * information is stored (in the form of a block of bitmap) * It also contains the pfns that correspond to the start and end of * the represented memory area. * * The memory bitmap is organized as a radix tree to guarantee fast random * access to the bits. There is one radix tree for each zone (as returned * from create_mem_extents). * * One radix tree is represented by one struct mem_zone_bm_rtree. There are * two linked lists for the nodes of the tree, one for the inner nodes and * one for the leave nodes. The linked leave nodes are used for fast linear * access of the memory bitmap. * * The struct rtree_node represents one node of the radix tree. */ #define BM_END_OF_MAP (~0UL) #define BM_BITS_PER_BLOCK (PAGE_SIZE * BITS_PER_BYTE) #define BM_BLOCK_SHIFT (PAGE_SHIFT + 3) #define BM_BLOCK_MASK ((1UL << BM_BLOCK_SHIFT) - 1) /* * struct rtree_node is a wrapper struct to link the nodes * of the rtree together for easy linear iteration over * bits and easy freeing */ struct rtree_node { struct list_head list; unsigned long *data; }; /* * struct mem_zone_bm_rtree represents a bitmap used for one * populated memory zone. */ struct mem_zone_bm_rtree { struct list_head list; /* Link Zones together */ struct list_head nodes; /* Radix Tree inner nodes */ struct list_head leaves; /* Radix Tree leaves */ unsigned long start_pfn; /* Zone start page frame */ unsigned long end_pfn; /* Zone end page frame + 1 */ struct rtree_node *rtree; /* Radix Tree Root */ int levels; /* Number of Radix Tree Levels */ unsigned int blocks; /* Number of Bitmap Blocks */ }; /* strcut bm_position is used for browsing memory bitmaps */ struct bm_position { struct mem_zone_bm_rtree *zone; struct rtree_node *node; unsigned long node_pfn; int node_bit; }; struct memory_bitmap { struct list_head zones; struct linked_page *p_list; /* list of pages used to store zone bitmap objects and bitmap block objects */ struct bm_position cur; /* most recently used bit position */ }; /* Functions that operate on memory bitmaps */ #define BM_ENTRIES_PER_LEVEL (PAGE_SIZE / sizeof(unsigned long)) #if BITS_PER_LONG == 32 #define BM_RTREE_LEVEL_SHIFT (PAGE_SHIFT - 2) #else #define BM_RTREE_LEVEL_SHIFT (PAGE_SHIFT - 3) #endif #define BM_RTREE_LEVEL_MASK ((1UL << BM_RTREE_LEVEL_SHIFT) - 1) /** * alloc_rtree_node - Allocate a new node and add it to the radix tree. * * This function is used to allocate inner nodes as well as the * leave nodes of the radix tree. It also adds the node to the * corresponding linked list passed in by the *list parameter. */ static struct rtree_node *alloc_rtree_node(gfp_t gfp_mask, int safe_needed, struct chain_allocator *ca, struct list_head *list) { struct rtree_node *node; node = chain_alloc(ca, sizeof(struct rtree_node)); if (!node) return NULL; node->data = get_image_page(gfp_mask, safe_needed); if (!node->data) return NULL; list_add_tail(&node->list, list); return node; } /** * add_rtree_block - Add a new leave node to the radix tree. * * The leave nodes need to be allocated in order to keep the leaves * linked list in order. This is guaranteed by the zone->blocks * counter. */ static int add_rtree_block(struct mem_zone_bm_rtree *zone, gfp_t gfp_mask, int safe_needed, struct chain_allocator *ca) { struct rtree_node *node, *block, **dst; unsigned int levels_needed, block_nr; int i; block_nr = zone->blocks; levels_needed = 0; /* How many levels do we need for this block nr? */ while (block_nr) { levels_needed += 1; block_nr >>= BM_RTREE_LEVEL_SHIFT; } /* Make sure the rtree has enough levels */ for (i = zone->levels; i < levels_needed; i++) { node = alloc_rtree_node(gfp_mask, safe_needed, ca, &zone->nodes); if (!node) return -ENOMEM; node->data[0] = (unsigned long)zone->rtree; zone->rtree = node; zone->levels += 1; } /* Allocate new block */ block = alloc_rtree_node(gfp_mask, safe_needed, ca, &zone->leaves); if (!block) return -ENOMEM; /* Now walk the rtree to insert the block */ node = zone->rtree; dst = &zone->rtree; block_nr = zone->blocks; for (i = zone->levels; i > 0; i--) { int index; if (!node) { node = alloc_rtree_node(gfp_mask, safe_needed, ca, &zone->nodes); if (!node) return -ENOMEM; *dst = node; } index = block_nr >> ((i - 1) * BM_RTREE_LEVEL_SHIFT); index &= BM_RTREE_LEVEL_MASK; dst = (struct rtree_node **)&((*dst)->data[index]); node = *dst; } zone->blocks += 1; *dst = block; return 0; } static void free_zone_bm_rtree(struct mem_zone_bm_rtree *zone, int clear_nosave_free); /** * create_zone_bm_rtree - Create a radix tree for one zone. * * Allocated the mem_zone_bm_rtree structure and initializes it. * This function also allocated and builds the radix tree for the * zone. */ static struct mem_zone_bm_rtree *create_zone_bm_rtree(gfp_t gfp_mask, int safe_needed, struct chain_allocator *ca, unsigned long start, unsigned long end) { struct mem_zone_bm_rtree *zone; unsigned int i, nr_blocks; unsigned long pages; pages = end - start; zone = chain_alloc(ca, sizeof(struct mem_zone_bm_rtree)); if (!zone) return NULL; INIT_LIST_HEAD(&zone->nodes); INIT_LIST_HEAD(&zone->leaves); zone->start_pfn = start; zone->end_pfn = end; nr_blocks = DIV_ROUND_UP(pages, BM_BITS_PER_BLOCK); for (i = 0; i < nr_blocks; i++) { if (add_rtree_block(zone, gfp_mask, safe_needed, ca)) { free_zone_bm_rtree(zone, PG_UNSAFE_CLEAR); return NULL; } } return zone; } /** * free_zone_bm_rtree - Free the memory of the radix tree. * * Free all node pages of the radix tree. The mem_zone_bm_rtree * structure itself is not freed here nor are the rtree_node * structs. */ static void free_zone_bm_rtree(struct mem_zone_bm_rtree *zone, int clear_nosave_free) { struct rtree_node *node; list_for_each_entry(node, &zone->nodes, list) free_image_page(node->data, clear_nosave_free); list_for_each_entry(node, &zone->leaves, list) free_image_page(node->data, clear_nosave_free); } static void memory_bm_position_reset(struct memory_bitmap *bm) { bm->cur.zone = list_entry(bm->zones.next, struct mem_zone_bm_rtree, list); bm->cur.node = list_entry(bm->cur.zone->leaves.next, struct rtree_node, list); bm->cur.node_pfn = 0; bm->cur.node_bit = 0; } static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free); struct mem_extent { struct list_head hook; unsigned long start; unsigned long end; }; /** * free_mem_extents - Free a list of memory extents. * @list: List of extents to free. */ static void free_mem_extents(struct list_head *list) { struct mem_extent *ext, *aux; list_for_each_entry_safe(ext, aux, list, hook) { list_del(&ext->hook); kfree(ext); } } /** * create_mem_extents - Create a list of memory extents. * @list: List to put the extents into. * @gfp_mask: Mask to use for memory allocations. * * The extents represent contiguous ranges of PFNs. */ static int create_mem_extents(struct list_head *list, gfp_t gfp_mask) { struct zone *zone; INIT_LIST_HEAD(list); for_each_populated_zone(zone) { unsigned long zone_start, zone_end; struct mem_extent *ext, *cur, *aux; zone_start = zone->zone_start_pfn; zone_end = zone_end_pfn(zone); list_for_each_entry(ext, list, hook) if (zone_start <= ext->end) break; if (&ext->hook == list || zone_end < ext->start) { /* New extent is necessary */ struct mem_extent *new_ext; new_ext = kzalloc(sizeof(struct mem_extent), gfp_mask); if (!new_ext) { free_mem_extents(list); return -ENOMEM; } new_ext->start = zone_start; new_ext->end = zone_end; list_add_tail(&new_ext->hook, &ext->hook); continue; } /* Merge this zone's range of PFNs with the existing one */ if (zone_start < ext->start) ext->start = zone_start; if (zone_end > ext->end) ext->end = zone_end; /* More merging may be possible */ cur = ext; list_for_each_entry_safe_continue(cur, aux, list, hook) { if (zone_end < cur->start) break; if (zone_end < cur->end) ext->end = cur->end; list_del(&cur->hook); kfree(cur); } } return 0; } /** * memory_bm_create - Allocate memory for a memory bitmap. */ static int memory_bm_create(struct memory_bitmap *bm, gfp_t gfp_mask, int safe_needed) { struct chain_allocator ca; struct list_head mem_extents; struct mem_extent *ext; int error; chain_init(&ca, gfp_mask, safe_needed); INIT_LIST_HEAD(&bm->zones); error = create_mem_extents(&mem_extents, gfp_mask); if (error) return error; list_for_each_entry(ext, &mem_extents, hook) { struct mem_zone_bm_rtree *zone; zone = create_zone_bm_rtree(gfp_mask, safe_needed, &ca, ext->start, ext->end); if (!zone) { error = -ENOMEM; goto Error; } list_add_tail(&zone->list, &bm->zones); } bm->p_list = ca.chain; memory_bm_position_reset(bm); Exit: free_mem_extents(&mem_extents); return error; Error: bm->p_list = ca.chain; memory_bm_free(bm, PG_UNSAFE_CLEAR); goto Exit; } /** * memory_bm_free - Free memory occupied by the memory bitmap. * @bm: Memory bitmap. */ static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free) { struct mem_zone_bm_rtree *zone; list_for_each_entry(zone, &bm->zones, list) free_zone_bm_rtree(zone, clear_nosave_free); free_list_of_pages(bm->p_list, clear_nosave_free); INIT_LIST_HEAD(&bm->zones); } /** * memory_bm_find_bit - Find the bit for a given PFN in a memory bitmap. * * Find the bit in memory bitmap @bm that corresponds to the given PFN. * The cur.zone, cur.block and cur.node_pfn members of @bm are updated. * * Walk the radix tree to find the page containing the bit that represents @pfn * and return the position of the bit in @addr and @bit_nr. */ static int memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn, void **addr, unsigned int *bit_nr) { struct mem_zone_bm_rtree *curr, *zone; struct rtree_node *node; int i, block_nr; zone = bm->cur.zone; if (pfn >= zone->start_pfn && pfn < zone->end_pfn) goto zone_found; zone = NULL; /* Find the right zone */ list_for_each_entry(curr, &bm->zones, list) { if (pfn >= curr->start_pfn && pfn < curr->end_pfn) { zone = curr; break; } } if (!zone) return -EFAULT; zone_found: /* * We have found the zone. Now walk the radix tree to find the leaf node * for our PFN. */ node = bm->cur.node; if (((pfn - zone->start_pfn) & ~BM_BLOCK_MASK) == bm->cur.node_pfn) goto node_found; node = zone->rtree; block_nr = (pfn - zone->start_pfn) >> BM_BLOCK_SHIFT; for (i = zone->levels; i > 0; i--) { int index; index = block_nr >> ((i - 1) * BM_RTREE_LEVEL_SHIFT); index &= BM_RTREE_LEVEL_MASK; BUG_ON(node->data[index] == 0); node = (struct rtree_node *)node->data[index]; } node_found: /* Update last position */ bm->cur.zone = zone; bm->cur.node = node; bm->cur.node_pfn = (pfn - zone->start_pfn) & ~BM_BLOCK_MASK; /* Set return values */ *addr = node->data; *bit_nr = (pfn - zone->start_pfn) & BM_BLOCK_MASK; return 0; } static void memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn) { void *addr; unsigned int bit; int error; error = memory_bm_find_bit(bm, pfn, &addr, &bit); BUG_ON(error); set_bit(bit, addr); } static int mem_bm_set_bit_check(struct memory_bitmap *bm, unsigned long pfn) { void *addr; unsigned int bit; int error; error = memory_bm_find_bit(bm, pfn, &addr, &bit); if (!error) set_bit(bit, addr); return error; } static void memory_bm_clear_bit(struct memory_bitmap *bm, unsigned long pfn) { void *addr; unsigned int bit; int error; error = memory_bm_find_bit(bm, pfn, &addr, &bit); BUG_ON(error); clear_bit(bit, addr); } static void memory_bm_clear_current(struct memory_bitmap *bm) { int bit; bit = max(bm->cur.node_bit - 1, 0); clear_bit(bit, bm->cur.node->data); } static int memory_bm_test_bit(struct memory_bitmap *bm, unsigned long pfn) { void *addr; unsigned int bit; int error; error = memory_bm_find_bit(bm, pfn, &addr, &bit); BUG_ON(error); return test_bit(bit, addr); } static bool memory_bm_pfn_present(struct memory_bitmap *bm, unsigned long pfn) { void *addr; unsigned int bit; return !memory_bm_find_bit(bm, pfn, &addr, &bit); } /* * rtree_next_node - Jump to the next leaf node. * * Set the position to the beginning of the next node in the * memory bitmap. This is either the next node in the current * zone's radix tree or the first node in the radix tree of the * next zone. * * Return true if there is a next node, false otherwise. */ static bool rtree_next_node(struct memory_bitmap *bm) { if (!list_is_last(&bm->cur.node->list, &bm->cur.zone->leaves)) { bm->cur.node = list_entry(bm->cur.node->list.next, struct rtree_node, list); bm->cur.node_pfn += BM_BITS_PER_BLOCK; bm->cur.node_bit = 0; touch_softlockup_watchdog(); return true; } /* No more nodes, goto next zone */ if (!list_is_last(&bm->cur.zone->list, &bm->zones)) { bm->cur.zone = list_entry(bm->cur.zone->list.next, struct mem_zone_bm_rtree, list); bm->cur.node = list_entry(bm->cur.zone->leaves.next, struct rtree_node, list); bm->cur.node_pfn = 0; bm->cur.node_bit = 0; return true; } /* No more zones */ return false; } /** * memory_bm_rtree_next_pfn - Find the next set bit in a memory bitmap. * @bm: Memory bitmap. * * Starting from the last returned position this function searches for the next * set bit in @bm and returns the PFN represented by it. If no more bits are * set, BM_END_OF_MAP is returned. * * It is required to run memory_bm_position_reset() before the first call to * this function for the given memory bitmap. */ static unsigned long memory_bm_next_pfn(struct memory_bitmap *bm) { unsigned long bits, pfn, pages; int bit; do { pages = bm->cur.zone->end_pfn - bm->cur.zone->start_pfn; bits = min(pages - bm->cur.node_pfn, BM_BITS_PER_BLOCK); bit = find_next_bit(bm->cur.node->data, bits, bm->cur.node_bit); if (bit < bits) { pfn = bm->cur.zone->start_pfn + bm->cur.node_pfn + bit; bm->cur.node_bit = bit + 1; return pfn; } } while (rtree_next_node(bm)); return BM_END_OF_MAP; } /* * This structure represents a range of page frames the contents of which * should not be saved during hibernation. */ struct nosave_region { struct list_head list; unsigned long start_pfn; unsigned long end_pfn; }; static LIST_HEAD(nosave_regions); static void recycle_zone_bm_rtree(struct mem_zone_bm_rtree *zone) { struct rtree_node *node; list_for_each_entry(node, &zone->nodes, list) recycle_safe_page(node->data); list_for_each_entry(node, &zone->leaves, list) recycle_safe_page(node->data); } static void memory_bm_recycle(struct memory_bitmap *bm) { struct mem_zone_bm_rtree *zone; struct linked_page *p_list; list_for_each_entry(zone, &bm->zones, list) recycle_zone_bm_rtree(zone); p_list = bm->p_list; while (p_list) { struct linked_page *lp = p_list; p_list = lp->next; recycle_safe_page(lp); } } /** * register_nosave_region - Register a region of unsaveable memory. * * Register a range of page frames the contents of which should not be saved * during hibernation (to be used in the early initialization code). */ void __init __register_nosave_region(unsigned long start_pfn, unsigned long end_pfn, int use_kmalloc) { struct nosave_region *region; if (start_pfn >= end_pfn) return; if (!list_empty(&nosave_regions)) { /* Try to extend the previous region (they should be sorted) */ region = list_entry(nosave_regions.prev, struct nosave_region, list); if (region->end_pfn == start_pfn) { region->end_pfn = end_pfn; goto Report; } } if (use_kmalloc) { /* During init, this shouldn't fail */ region = kmalloc(sizeof(struct nosave_region), GFP_KERNEL); BUG_ON(!region); } else { /* This allocation cannot fail */ region = memblock_alloc(sizeof(struct nosave_region), SMP_CACHE_BYTES); if (!region) panic("%s: Failed to allocate %zu bytes\n", __func__, sizeof(struct nosave_region)); } region->start_pfn = start_pfn; region->end_pfn = end_pfn; list_add_tail(&region->list, &nosave_regions); Report: pr_info("Registered nosave memory: [mem %#010llx-%#010llx]\n", (unsigned long long) start_pfn << PAGE_SHIFT, ((unsigned long long) end_pfn << PAGE_SHIFT) - 1); } /* * Set bits in this map correspond to the page frames the contents of which * should not be saved during the suspend. */ static struct memory_bitmap *forbidden_pages_map; /* Set bits in this map correspond to free page frames. */ static struct memory_bitmap *free_pages_map; /* * Each page frame allocated for creating the image is marked by setting the * corresponding bits in forbidden_pages_map and free_pages_map simultaneously */ void swsusp_set_page_free(struct page *page) { if (free_pages_map) memory_bm_set_bit(free_pages_map, page_to_pfn(page)); } static int swsusp_page_is_free(struct page *page) { return free_pages_map ? memory_bm_test_bit(free_pages_map, page_to_pfn(page)) : 0; } void swsusp_unset_page_free(struct page *page) { if (free_pages_map) memory_bm_clear_bit(free_pages_map, page_to_pfn(page)); } static void swsusp_set_page_forbidden(struct page *page) { if (forbidden_pages_map) memory_bm_set_bit(forbidden_pages_map, page_to_pfn(page)); } int swsusp_page_is_forbidden(struct page *page) { return forbidden_pages_map ? memory_bm_test_bit(forbidden_pages_map, page_to_pfn(page)) : 0; } static void swsusp_unset_page_forbidden(struct page *page) { if (forbidden_pages_map) memory_bm_clear_bit(forbidden_pages_map, page_to_pfn(page)); } /** * mark_nosave_pages - Mark pages that should not be saved. * @bm: Memory bitmap. * * Set the bits in @bm that correspond to the page frames the contents of which * should not be saved. */ static void mark_nosave_pages(struct memory_bitmap *bm) { struct nosave_region *region; if (list_empty(&nosave_regions)) return; list_for_each_entry(region, &nosave_regions, list) { unsigned long pfn; pr_debug("Marking nosave pages: [mem %#010llx-%#010llx]\n", (unsigned long long) region->start_pfn << PAGE_SHIFT, ((unsigned long long) region->end_pfn << PAGE_SHIFT) - 1); for (pfn = region->start_pfn; pfn < region->end_pfn; pfn++) if (pfn_valid(pfn)) { /* * It is safe to ignore the result of * mem_bm_set_bit_check() here, since we won't * touch the PFNs for which the error is * returned anyway. */ mem_bm_set_bit_check(bm, pfn); } } } /** * create_basic_memory_bitmaps - Create bitmaps to hold basic page information. * * Create bitmaps needed for marking page frames that should not be saved and * free page frames. The forbidden_pages_map and free_pages_map pointers are * only modified if everything goes well, because we don't want the bits to be * touched before both bitmaps are set up. */ int create_basic_memory_bitmaps(void) { struct memory_bitmap *bm1, *bm2; int error = 0; if (forbidden_pages_map && free_pages_map) return 0; else BUG_ON(forbidden_pages_map || free_pages_map); bm1 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL); if (!bm1) return -ENOMEM; error = memory_bm_create(bm1, GFP_KERNEL, PG_ANY); if (error) goto Free_first_object; bm2 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL); if (!bm2) goto Free_first_bitmap; error = memory_bm_create(bm2, GFP_KERNEL, PG_ANY); if (error) goto Free_second_object; forbidden_pages_map = bm1; free_pages_map = bm2; mark_nosave_pages(forbidden_pages_map); pr_debug("Basic memory bitmaps created\n"); return 0; Free_second_object: kfree(bm2); Free_first_bitmap: memory_bm_free(bm1, PG_UNSAFE_CLEAR); Free_first_object: kfree(bm1); return -ENOMEM; } /** * free_basic_memory_bitmaps - Free memory bitmaps holding basic information. * * Free memory bitmaps allocated by create_basic_memory_bitmaps(). The * auxiliary pointers are necessary so that the bitmaps themselves are not * referred to while they are being freed. */ void free_basic_memory_bitmaps(void) { struct memory_bitmap *bm1, *bm2; if (WARN_ON(!(forbidden_pages_map && free_pages_map))) return; bm1 = forbidden_pages_map; bm2 = free_pages_map; forbidden_pages_map = NULL; free_pages_map = NULL; memory_bm_free(bm1, PG_UNSAFE_CLEAR); kfree(bm1); memory_bm_free(bm2, PG_UNSAFE_CLEAR); kfree(bm2); pr_debug("Basic memory bitmaps freed\n"); } void clear_free_pages(void) { #ifdef CONFIG_PAGE_POISONING_ZERO struct memory_bitmap *bm = free_pages_map; unsigned long pfn; if (WARN_ON(!(free_pages_map))) return; memory_bm_position_reset(bm); pfn = memory_bm_next_pfn(bm); while (pfn != BM_END_OF_MAP) { if (pfn_valid(pfn)) clear_highpage(pfn_to_page(pfn)); pfn = memory_bm_next_pfn(bm); } memory_bm_position_reset(bm); pr_info("free pages cleared after restore\n"); #endif /* PAGE_POISONING_ZERO */ } /** * snapshot_additional_pages - Estimate the number of extra pages needed. * @zone: Memory zone to carry out the computation for. * * Estimate the number of additional pages needed for setting up a hibernation * image data structures for @zone (usually, the returned value is greater than * the exact number). */ unsigned int snapshot_additional_pages(struct zone *zone) { unsigned int rtree, nodes; rtree = nodes = DIV_ROUND_UP(zone->spanned_pages, BM_BITS_PER_BLOCK); rtree += DIV_ROUND_UP(rtree * sizeof(struct rtree_node), LINKED_PAGE_DATA_SIZE); while (nodes > 1) { nodes = DIV_ROUND_UP(nodes, BM_ENTRIES_PER_LEVEL); rtree += nodes; } return 2 * rtree; } #ifdef CONFIG_HIGHMEM /** * count_free_highmem_pages - Compute the total number of free highmem pages. * * The returned number is system-wide. */ static unsigned int count_free_highmem_pages(void) { struct zone *zone; unsigned int cnt = 0; for_each_populated_zone(zone) if (is_highmem(zone)) cnt += zone_page_state(zone, NR_FREE_PAGES); return cnt; } /** * saveable_highmem_page - Check if a highmem page is saveable. * * Determine whether a highmem page should be included in a hibernation image. * * We should save the page if it isn't Nosave or NosaveFree, or Reserved, * and it isn't part of a free chunk of pages. */ static struct page *saveable_highmem_page(struct zone *zone, unsigned long pfn) { struct page *page; if (!pfn_valid(pfn)) return NULL; page = pfn_to_online_page(pfn); if (!page || page_zone(page) != zone) return NULL; BUG_ON(!PageHighMem(page)); if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page)) return NULL; if (PageReserved(page) || PageOffline(page)) return NULL; if (page_is_guard(page)) return NULL; return page; } /** * count_highmem_pages - Compute the total number of saveable highmem pages. */ static unsigned int count_highmem_pages(void) { struct zone *zone; unsigned int n = 0; for_each_populated_zone(zone) { unsigned long pfn, max_zone_pfn; if (!is_highmem(zone)) continue; mark_free_pages(zone); max_zone_pfn = zone_end_pfn(zone); for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) if (saveable_highmem_page(zone, pfn)) n++; } return n; } #else static inline void *saveable_highmem_page(struct zone *z, unsigned long p) { return NULL; } #endif /* CONFIG_HIGHMEM */ /** * saveable_page - Check if the given page is saveable. * * Determine whether a non-highmem page should be included in a hibernation * image. * * We should save the page if it isn't Nosave, and is not in the range * of pages statically defined as 'unsaveable', and it isn't part of * a free chunk of pages. */ static struct page *saveable_page(struct zone *zone, unsigned long pfn) { struct page *page; if (!pfn_valid(pfn)) return NULL; page = pfn_to_online_page(pfn); if (!page || page_zone(page) != zone) return NULL; BUG_ON(PageHighMem(page)); if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page)) return NULL; if (PageOffline(page)) return NULL; if (PageReserved(page) && (!kernel_page_present(page) || pfn_is_nosave(pfn))) return NULL; if (page_is_guard(page)) return NULL; return page; } /** * count_data_pages - Compute the total number of saveable non-highmem pages. */ static unsigned int count_data_pages(void) { struct zone *zone; unsigned long pfn, max_zone_pfn; unsigned int n = 0; for_each_populated_zone(zone) { if (is_highmem(zone)) continue; mark_free_pages(zone); max_zone_pfn = zone_end_pfn(zone); for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) if (saveable_page(zone, pfn)) n++; } return n; } /* * This is needed, because copy_page and memcpy are not usable for copying * task structs. */ static inline void do_copy_page(long *dst, long *src) { int n; for (n = PAGE_SIZE / sizeof(long); n; n--) *dst++ = *src++; } /** * safe_copy_page - Copy a page in a safe way. * * Check if the page we are going to copy is marked as present in the kernel * page tables. This always is the case if CONFIG_DEBUG_PAGEALLOC or * CONFIG_ARCH_HAS_SET_DIRECT_MAP is not set. In that case kernel_page_present() * always returns 'true'. */ static void safe_copy_page(void *dst, struct page *s_page) { if (kernel_page_present(s_page)) { do_copy_page(dst, page_address(s_page)); } else { kernel_map_pages(s_page, 1, 1); do_copy_page(dst, page_address(s_page)); kernel_map_pages(s_page, 1, 0); } } #ifdef CONFIG_HIGHMEM static inline struct page *page_is_saveable(struct zone *zone, unsigned long pfn) { return is_highmem(zone) ? saveable_highmem_page(zone, pfn) : saveable_page(zone, pfn); } static void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) { struct page *s_page, *d_page; void *src, *dst; s_page = pfn_to_page(src_pfn); d_page = pfn_to_page(dst_pfn); if (PageHighMem(s_page)) { src = kmap_atomic(s_page); dst = kmap_atomic(d_page); do_copy_page(dst, src); kunmap_atomic(dst); kunmap_atomic(src); } else { if (PageHighMem(d_page)) { /* * The page pointed to by src may contain some kernel * data modified by kmap_atomic() */ safe_copy_page(buffer, s_page); dst = kmap_atomic(d_page); copy_page(dst, buffer); kunmap_atomic(dst); } else { safe_copy_page(page_address(d_page), s_page); } } } #else #define page_is_saveable(zone, pfn) saveable_page(zone, pfn) static inline void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) { safe_copy_page(page_address(pfn_to_page(dst_pfn)), pfn_to_page(src_pfn)); } #endif /* CONFIG_HIGHMEM */ static void copy_data_pages(struct memory_bitmap *copy_bm, struct memory_bitmap *orig_bm) { struct zone *zone; unsigned long pfn; for_each_populated_zone(zone) { unsigned long max_zone_pfn; mark_free_pages(zone); max_zone_pfn = zone_end_pfn(zone); for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) if (page_is_saveable(zone, pfn)) memory_bm_set_bit(orig_bm, pfn); } memory_bm_position_reset(orig_bm); memory_bm_position_reset(copy_bm); for(;;) { pfn = memory_bm_next_pfn(orig_bm); if (unlikely(pfn == BM_END_OF_MAP)) break; copy_data_page(memory_bm_next_pfn(copy_bm), pfn); } } /* Total number of image pages */ static unsigned int nr_copy_pages; /* Number of pages needed for saving the original pfns of the image pages */ static unsigned int nr_meta_pages; /* * Numbers of normal and highmem page frames allocated for hibernation image * before suspending devices. */ static unsigned int alloc_normal, alloc_highmem; /* * Memory bitmap used for marking saveable pages (during hibernation) or * hibernation image pages (during restore) */ static struct memory_bitmap orig_bm; /* * Memory bitmap used during hibernation for marking allocated page frames that * will contain copies of saveable pages. During restore it is initially used * for marking hibernation image pages, but then the set bits from it are * duplicated in @orig_bm and it is released. On highmem systems it is next * used for marking "safe" highmem pages, but it has to be reinitialized for * this purpose. */ static struct memory_bitmap copy_bm; /** * swsusp_free - Free pages allocated for hibernation image. * * Image pages are alocated before snapshot creation, so they need to be * released after resume. */ void swsusp_free(void) { unsigned long fb_pfn, fr_pfn; if (!forbidden_pages_map || !free_pages_map) goto out; memory_bm_position_reset(forbidden_pages_map); memory_bm_position_reset(free_pages_map); loop: fr_pfn = memory_bm_next_pfn(free_pages_map); fb_pfn = memory_bm_next_pfn(forbidden_pages_map); /* * Find the next bit set in both bitmaps. This is guaranteed to * terminate when fb_pfn == fr_pfn == BM_END_OF_MAP. */ do { if (fb_pfn < fr_pfn) fb_pfn = memory_bm_next_pfn(forbidden_pages_map); if (fr_pfn < fb_pfn) fr_pfn = memory_bm_next_pfn(free_pages_map); } while (fb_pfn != fr_pfn); if (fr_pfn != BM_END_OF_MAP && pfn_valid(fr_pfn)) { struct page *page = pfn_to_page(fr_pfn); memory_bm_clear_current(forbidden_pages_map); memory_bm_clear_current(free_pages_map); hibernate_restore_unprotect_page(page_address(page)); __free_page(page); goto loop; } out: nr_copy_pages = 0; nr_meta_pages = 0; restore_pblist = NULL; buffer = NULL; alloc_normal = 0; alloc_highmem = 0; hibernate_restore_protection_end(); } /* Helper functions used for the shrinking of memory. */ #define GFP_IMAGE (GFP_KERNEL | __GFP_NOWARN) /** * preallocate_image_pages - Allocate a number of pages for hibernation image. * @nr_pages: Number of page frames to allocate. * @mask: GFP flags to use for the allocation. * * Return value: Number of page frames actually allocated */ static unsigned long preallocate_image_pages(unsigned long nr_pages, gfp_t mask) { unsigned long nr_alloc = 0; while (nr_pages > 0) { struct page *page; page = alloc_image_page(mask); if (!page) break; memory_bm_set_bit(&copy_bm, page_to_pfn(page)); if (PageHighMem(page)) alloc_highmem++; else alloc_normal++; nr_pages--; nr_alloc++; } return nr_alloc; } static unsigned long preallocate_image_memory(unsigned long nr_pages, unsigned long avail_normal) { unsigned long alloc; if (avail_normal <= alloc_normal) return 0; alloc = avail_normal - alloc_normal; if (nr_pages < alloc) alloc = nr_pages; return preallocate_image_pages(alloc, GFP_IMAGE); } #ifdef CONFIG_HIGHMEM static unsigned long preallocate_image_highmem(unsigned long nr_pages) { return preallocate_image_pages(nr_pages, GFP_IMAGE | __GFP_HIGHMEM); } /** * __fraction - Compute (an approximation of) x * (multiplier / base). */ static unsigned long __fraction(u64 x, u64 multiplier, u64 base) { x *= multiplier; do_div(x, base); return (unsigned long)x; } static unsigned long preallocate_highmem_fraction(unsigned long nr_pages, unsigned long highmem, unsigned long total) { unsigned long alloc = __fraction(nr_pages, highmem, total); return preallocate_image_pages(alloc, GFP_IMAGE | __GFP_HIGHMEM); } #else /* CONFIG_HIGHMEM */ static inline unsigned long preallocate_image_highmem(unsigned long nr_pages) { return 0; } static inline unsigned long preallocate_highmem_fraction(unsigned long nr_pages, unsigned long highmem, unsigned long total) { return 0; } #endif /* CONFIG_HIGHMEM */ /** * free_unnecessary_pages - Release preallocated pages not needed for the image. */ static unsigned long free_unnecessary_pages(void) { unsigned long save, to_free_normal, to_free_highmem, free; save = count_data_pages(); if (alloc_normal >= save) { to_free_normal = alloc_normal - save; save = 0; } else { to_free_normal = 0; save -= alloc_normal; } save += count_highmem_pages(); if (alloc_highmem >= save) { to_free_highmem = alloc_highmem - save; } else { to_free_highmem = 0; save -= alloc_highmem; if (to_free_normal > save) to_free_normal -= save; else to_free_normal = 0; } free = to_free_normal + to_free_highmem; memory_bm_position_reset(&copy_bm); while (to_free_normal > 0 || to_free_highmem > 0) { unsigned long pfn = memory_bm_next_pfn(&copy_bm); struct page *page = pfn_to_page(pfn); if (PageHighMem(page)) { if (!to_free_highmem) continue; to_free_highmem--; alloc_highmem--; } else { if (!to_free_normal) continue; to_free_normal--; alloc_normal--; } memory_bm_clear_bit(&copy_bm, pfn); swsusp_unset_page_forbidden(page); swsusp_unset_page_free(page); __free_page(page); } return free; } /** * minimum_image_size - Estimate the minimum acceptable size of an image. * @saveable: Number of saveable pages in the system. * * We want to avoid attempting to free too much memory too hard, so estimate the * minimum acceptable size of a hibernation image to use as the lower limit for * preallocating memory. * * We assume that the minimum image size should be proportional to * * [number of saveable pages] - [number of pages that can be freed in theory] * * where the second term is the sum of (1) reclaimable slab pages, (2) active * and (3) inactive anonymous pages, (4) active and (5) inactive file pages. */ static unsigned long minimum_image_size(unsigned long saveable) { unsigned long size; size = global_node_page_state(NR_SLAB_RECLAIMABLE) + global_node_page_state(NR_ACTIVE_ANON) + global_node_page_state(NR_INACTIVE_ANON) + global_node_page_state(NR_ACTIVE_FILE) + global_node_page_state(NR_INACTIVE_FILE); return saveable <= size ? 0 : saveable - size; } /** * hibernate_preallocate_memory - Preallocate memory for hibernation image. * * To create a hibernation image it is necessary to make a copy of every page * frame in use. We also need a number of page frames to be free during * hibernation for allocations made while saving the image and for device * drivers, in case they need to allocate memory from their hibernation * callbacks (these two numbers are given by PAGES_FOR_IO (which is a rough * estimate) and reserverd_size divided by PAGE_SIZE (which is tunable through * /sys/power/reserved_size, respectively). To make this happen, we compute the * total number of available page frames and allocate at least * * ([page frames total] + PAGES_FOR_IO + [metadata pages]) / 2 * + 2 * DIV_ROUND_UP(reserved_size, PAGE_SIZE) * * of them, which corresponds to the maximum size of a hibernation image. * * If image_size is set below the number following from the above formula, * the preallocation of memory is continued until the total number of saveable * pages in the system is below the requested image size or the minimum * acceptable image size returned by minimum_image_size(), whichever is greater. */ int hibernate_preallocate_memory(void) { struct zone *zone; unsigned long saveable, size, max_size, count, highmem, pages = 0; unsigned long alloc, save_highmem, pages_highmem, avail_normal; ktime_t start, stop; int error; pr_info("Preallocating image memory... "); start = ktime_get(); error = memory_bm_create(&orig_bm, GFP_IMAGE, PG_ANY); if (error) goto err_out; error = memory_bm_create(&copy_bm, GFP_IMAGE, PG_ANY); if (error) goto err_out; alloc_normal = 0; alloc_highmem = 0; /* Count the number of saveable data pages. */ save_highmem = count_highmem_pages(); saveable = count_data_pages(); /* * Compute the total number of page frames we can use (count) and the * number of pages needed for image metadata (size). */ count = saveable; saveable += save_highmem; highmem = save_highmem; size = 0; for_each_populated_zone(zone) { size += snapshot_additional_pages(zone); if (is_highmem(zone)) highmem += zone_page_state(zone, NR_FREE_PAGES); else count += zone_page_state(zone, NR_FREE_PAGES); } avail_normal = count; count += highmem; count -= totalreserve_pages; /* Add number of pages required for page keys (s390 only). */ size += page_key_additional_pages(saveable); /* Compute the maximum number of saveable pages to leave in memory. */ max_size = (count - (size + PAGES_FOR_IO)) / 2 - 2 * DIV_ROUND_UP(reserved_size, PAGE_SIZE); /* Compute the desired number of image pages specified by image_size. */ size = DIV_ROUND_UP(image_size, PAGE_SIZE); if (size > max_size) size = max_size; /* * If the desired number of image pages is at least as large as the * current number of saveable pages in memory, allocate page frames for * the image and we're done. */ if (size >= saveable) { pages = preallocate_image_highmem(save_highmem); pages += preallocate_image_memory(saveable - pages, avail_normal); goto out; } /* Estimate the minimum size of the image. */ pages = minimum_image_size(saveable); /* * To avoid excessive pressure on the normal zone, leave room in it to * accommodate an image of the minimum size (unless it's already too * small, in which case don't preallocate pages from it at all). */ if (avail_normal > pages) avail_normal -= pages; else avail_normal = 0; if (size < pages) size = min_t(unsigned long, pages, max_size); /* * Let the memory management subsystem know that we're going to need a * large number of page frames to allocate and make it free some memory. * NOTE: If this is not done, performance will be hurt badly in some * test cases. */ shrink_all_memory(saveable - size); /* * The number of saveable pages in memory was too high, so apply some * pressure to decrease it. First, make room for the largest possible * image and fail if that doesn't work. Next, try to decrease the size * of the image as much as indicated by 'size' using allocations from * highmem and non-highmem zones separately. */ pages_highmem = preallocate_image_highmem(highmem / 2); alloc = count - max_size; if (alloc > pages_highmem) alloc -= pages_highmem; else alloc = 0; pages = preallocate_image_memory(alloc, avail_normal); if (pages < alloc) { /* We have exhausted non-highmem pages, try highmem. */ alloc -= pages; pages += pages_highmem; pages_highmem = preallocate_image_highmem(alloc); if (pages_highmem < alloc) goto err_out; pages += pages_highmem; /* * size is the desired number of saveable pages to leave in * memory, so try to preallocate (all memory - size) pages. */ alloc = (count - pages) - size; pages += preallocate_image_highmem(alloc); } else { /* * There are approximately max_size saveable pages at this point * and we want to reduce this number down to size. */ alloc = max_size - size; size = preallocate_highmem_fraction(alloc, highmem, count); pages_highmem += size; alloc -= size; size = preallocate_image_memory(alloc, avail_normal); pages_highmem += preallocate_image_highmem(alloc - size); pages += pages_highmem + size; } /* * We only need as many page frames for the image as there are saveable * pages in memory, but we have allocated more. Release the excessive * ones now. */ pages -= free_unnecessary_pages(); out: stop = ktime_get(); pr_cont("done (allocated %lu pages)\n", pages); swsusp_show_speed(start, stop, pages, "Allocated"); return 0; err_out: pr_cont("\n"); swsusp_free(); return -ENOMEM; } #ifdef CONFIG_HIGHMEM /** * count_pages_for_highmem - Count non-highmem pages needed for copying highmem. * * Compute the number of non-highmem pages that will be necessary for creating * copies of highmem pages. */ static unsigned int count_pages_for_highmem(unsigned int nr_highmem) { unsigned int free_highmem = count_free_highmem_pages() + alloc_highmem; if (free_highmem >= nr_highmem) nr_highmem = 0; else nr_highmem -= free_highmem; return nr_highmem; } #else static unsigned int count_pages_for_highmem(unsigned int nr_highmem) { return 0; } #endif /* CONFIG_HIGHMEM */ /** * enough_free_mem - Check if there is enough free memory for the image. */ static int enough_free_mem(unsigned int nr_pages, unsigned int nr_highmem) { struct zone *zone; unsigned int free = alloc_normal; for_each_populated_zone(zone) if (!is_highmem(zone)) free += zone_page_state(zone, NR_FREE_PAGES); nr_pages += count_pages_for_highmem(nr_highmem); pr_debug("Normal pages needed: %u + %u, available pages: %u\n", nr_pages, PAGES_FOR_IO, free); return free > nr_pages + PAGES_FOR_IO; } #ifdef CONFIG_HIGHMEM /** * get_highmem_buffer - Allocate a buffer for highmem pages. * * If there are some highmem pages in the hibernation image, we may need a * buffer to copy them and/or load their data. */ static inline int get_highmem_buffer(int safe_needed) { buffer = get_image_page(GFP_ATOMIC, safe_needed); return buffer ? 0 : -ENOMEM; } /** * alloc_highmem_image_pages - Allocate some highmem pages for the image. * * Try to allocate as many pages as needed, but if the number of free highmem * pages is less than that, allocate them all. */ static inline unsigned int alloc_highmem_pages(struct memory_bitmap *bm, unsigned int nr_highmem) { unsigned int to_alloc = count_free_highmem_pages(); if (to_alloc > nr_highmem) to_alloc = nr_highmem; nr_highmem -= to_alloc; while (to_alloc-- > 0) { struct page *page; page = alloc_image_page(__GFP_HIGHMEM|__GFP_KSWAPD_RECLAIM); memory_bm_set_bit(bm, page_to_pfn(page)); } return nr_highmem; } #else static inline int get_highmem_buffer(int safe_needed) { return 0; } static inline unsigned int alloc_highmem_pages(struct memory_bitmap *bm, unsigned int n) { return 0; } #endif /* CONFIG_HIGHMEM */ /** * swsusp_alloc - Allocate memory for hibernation image. * * We first try to allocate as many highmem pages as there are * saveable highmem pages in the system. If that fails, we allocate * non-highmem pages for the copies of the remaining highmem ones. * * In this approach it is likely that the copies of highmem pages will * also be located in the high memory, because of the way in which * copy_data_pages() works. */ static int swsusp_alloc(struct memory_bitmap *copy_bm, unsigned int nr_pages, unsigned int nr_highmem) { if (nr_highmem > 0) { if (get_highmem_buffer(PG_ANY)) goto err_out; if (nr_highmem > alloc_highmem) { nr_highmem -= alloc_highmem; nr_pages += alloc_highmem_pages(copy_bm, nr_highmem); } } if (nr_pages > alloc_normal) { nr_pages -= alloc_normal; while (nr_pages-- > 0) { struct page *page; page = alloc_image_page(GFP_ATOMIC); if (!page) goto err_out; memory_bm_set_bit(copy_bm, page_to_pfn(page)); } } return 0; err_out: swsusp_free(); return -ENOMEM; } asmlinkage __visible int swsusp_save(void) { unsigned int nr_pages, nr_highmem; pr_info("Creating hibernation image:\n"); drain_local_pages(NULL); nr_pages = count_data_pages(); nr_highmem = count_highmem_pages(); pr_info("Need to copy %u pages\n", nr_pages + nr_highmem); if (!enough_free_mem(nr_pages, nr_highmem)) { pr_err("Not enough free memory\n"); return -ENOMEM; } if (swsusp_alloc(&copy_bm, nr_pages, nr_highmem)) { pr_err("Memory allocation failed\n"); return -ENOMEM; } /* * During allocating of suspend pagedir, new cold pages may appear. * Kill them. */ drain_local_pages(NULL); copy_data_pages(&copy_bm, &orig_bm); /* * End of critical section. From now on, we can write to memory, * but we should not touch disk. This specially means we must _not_ * touch swap space! Except we must write out our image of course. */ nr_pages += nr_highmem; nr_copy_pages = nr_pages; nr_meta_pages = DIV_ROUND_UP(nr_pages * sizeof(long), PAGE_SIZE); pr_info("Hibernation image created (%d pages copied)\n", nr_pages); return 0; } #ifndef CONFIG_ARCH_HIBERNATION_HEADER static int init_header_complete(struct swsusp_info *info) { memcpy(&info->uts, init_utsname(), sizeof(struct new_utsname)); info->version_code = LINUX_VERSION_CODE; return 0; } static char *check_image_kernel(struct swsusp_info *info) { if (info->version_code != LINUX_VERSION_CODE) return "kernel version"; if (strcmp(info->uts.sysname,init_utsname()->sysname)) return "system type"; if (strcmp(info->uts.release,init_utsname()->release)) return "kernel release"; if (strcmp(info->uts.version,init_utsname()->version)) return "version"; if (strcmp(info->uts.machine,init_utsname()->machine)) return "machine"; return NULL; } #endif /* CONFIG_ARCH_HIBERNATION_HEADER */ unsigned long snapshot_get_image_size(void) { return nr_copy_pages + nr_meta_pages + 1; } static int init_header(struct swsusp_info *info) { memset(info, 0, sizeof(struct swsusp_info)); info->num_physpages = get_num_physpages(); info->image_pages = nr_copy_pages; info->pages = snapshot_get_image_size(); info->size = info->pages; info->size <<= PAGE_SHIFT; return init_header_complete(info); } /** * pack_pfns - Prepare PFNs for saving. * @bm: Memory bitmap. * @buf: Memory buffer to store the PFNs in. * * PFNs corresponding to set bits in @bm are stored in the area of memory * pointed to by @buf (1 page at a time). */ static inline void pack_pfns(unsigned long *buf, struct memory_bitmap *bm) { int j; for (j = 0; j < PAGE_SIZE / sizeof(long); j++) { buf[j] = memory_bm_next_pfn(bm); if (unlikely(buf[j] == BM_END_OF_MAP)) break; /* Save page key for data page (s390 only). */ page_key_read(buf + j); } } /** * snapshot_read_next - Get the address to read the next image page from. * @handle: Snapshot handle to be used for the reading. * * On the first call, @handle should point to a zeroed snapshot_handle * structure. The structure gets populated then and a pointer to it should be * passed to this function every next time. * * On success, the function returns a positive number. Then, the caller * is allowed to read up to the returned number of bytes from the memory * location computed by the data_of() macro. * * The function returns 0 to indicate the end of the data stream condition, * and negative numbers are returned on errors. If that happens, the structure * pointed to by @handle is not updated and should not be used any more. */ int snapshot_read_next(struct snapshot_handle *handle) { if (handle->cur > nr_meta_pages + nr_copy_pages) return 0; if (!buffer) { /* This makes the buffer be freed by swsusp_free() */ buffer = get_image_page(GFP_ATOMIC, PG_ANY); if (!buffer) return -ENOMEM; } if (!handle->cur) { int error; error = init_header((struct swsusp_info *)buffer); if (error) return error; handle->buffer = buffer; memory_bm_position_reset(&orig_bm); memory_bm_position_reset(&copy_bm); } else if (handle->cur <= nr_meta_pages) { clear_page(buffer); pack_pfns(buffer, &orig_bm); } else { struct page *page; page = pfn_to_page(memory_bm_next_pfn(&copy_bm)); if (PageHighMem(page)) { /* * Highmem pages are copied to the buffer, * because we can't return with a kmapped * highmem page (we may not be called again). */ void *kaddr; kaddr = kmap_atomic(page); copy_page(buffer, kaddr); kunmap_atomic(kaddr); handle->buffer = buffer; } else { handle->buffer = page_address(page); } } handle->cur++; return PAGE_SIZE; } static void duplicate_memory_bitmap(struct memory_bitmap *dst, struct memory_bitmap *src) { unsigned long pfn; memory_bm_position_reset(src); pfn = memory_bm_next_pfn(src); while (pfn != BM_END_OF_MAP) { memory_bm_set_bit(dst, pfn); pfn = memory_bm_next_pfn(src); } } /** * mark_unsafe_pages - Mark pages that were used before hibernation. * * Mark the pages that cannot be used for storing the image during restoration, * because they conflict with the pages that had been used before hibernation. */


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