#include <linux/pagemap.h>
#include <linux/highmem.h>
#include <linux/mutex.h>
-#include <linux/highmem.h>
#include <linux/list.h>
#include <linux/sysdev.h>
+#include <linux/gfp.h>
-#include <asm/xen/hypervisor.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/uaccess.h>
#include <asm/tlb.h>
+#include <asm/xen/hypervisor.h>
+#include <asm/xen/hypercall.h>
+
+#include <xen/xen.h>
+#include <xen/interface/xen.h>
#include <xen/interface/memory.h>
-#include <xen/balloon.h>
#include <xen/xenbus.h>
#include <xen/features.h>
#include <xen/page.h>
#define PAGES2KB(_p) ((_p)<<(PAGE_SHIFT-10))
-#define BALLOON_CLASS_NAME "memory"
+#define BALLOON_CLASS_NAME "xen_memory"
struct balloon_stats {
/* We aim for 'current allocation' == 'target allocation'. */
unsigned long current_pages;
unsigned long target_pages;
- /* We may hit the hard limit in Xen. If we do then we remember it. */
- unsigned long hard_limit;
/*
* Drivers may alter the memory reservation independently, but they
* must inform the balloon driver so we avoid hitting the hard limit.
/* We increase/decrease in batches which fit in a page */
static unsigned long frame_list[PAGE_SIZE / sizeof(unsigned long)];
-/* VM /proc information for memory */
-extern unsigned long totalram_pages;
-
#ifdef CONFIG_HIGHMEM
-extern unsigned long totalhigh_pages;
#define inc_totalhigh_pages() (totalhigh_pages++)
#define dec_totalhigh_pages() (totalhigh_pages--)
#else
static void scrub_page(struct page *page)
{
#ifdef CONFIG_XEN_SCRUB_PAGES
- if (PageHighMem(page)) {
- void *v = kmap(page);
- clear_page(v);
- kunmap(v);
- } else {
- void *v = page_address(page);
- clear_page(v);
- }
+ clear_highpage(page);
#endif
}
list_add(&page->lru, &ballooned_pages);
balloon_stats.balloon_low++;
}
+
+ totalram_pages--;
}
/* balloon_retrieve: rescue a page from the balloon, if it is not empty. */
else
balloon_stats.balloon_low--;
+ totalram_pages++;
+
return page;
}
static unsigned long current_target(void)
{
- unsigned long target = min(balloon_stats.target_pages, balloon_stats.hard_limit);
+ unsigned long target = balloon_stats.target_pages;
target = min(target,
balloon_stats.current_pages +
page = balloon_first_page();
for (i = 0; i < nr_pages; i++) {
BUG_ON(page == NULL);
- frame_list[i] = page_to_pfn(page);;
+ frame_list[i] = page_to_pfn(page);
page = balloon_next_page(page);
}
set_xen_guest_handle(reservation.extent_start, frame_list);
- reservation.nr_extents = nr_pages;
- rc = HYPERVISOR_memory_op(
- XENMEM_populate_physmap, &reservation);
- if (rc < nr_pages) {
- if (rc > 0) {
- int ret;
-
- /* We hit the Xen hard limit: reprobe. */
- reservation.nr_extents = rc;
- ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation,
- &reservation);
- BUG_ON(ret != rc);
- }
- if (rc >= 0)
- balloon_stats.hard_limit = (balloon_stats.current_pages + rc -
- balloon_stats.driver_pages);
+ reservation.nr_extents = nr_pages;
+ rc = HYPERVISOR_memory_op(XENMEM_populate_physmap, &reservation);
+ if (rc < 0)
goto out;
- }
- for (i = 0; i < nr_pages; i++) {
+ for (i = 0; i < rc; i++) {
page = balloon_retrieve();
BUG_ON(page == NULL);
__free_page(page);
}
- balloon_stats.current_pages += nr_pages;
- totalram_pages = balloon_stats.current_pages;
+ balloon_stats.current_pages += rc;
out:
spin_unlock_irqrestore(&balloon_lock, flags);
- return 0;
+ return rc < 0 ? rc : rc != nr_pages;
}
static int decrease_reservation(unsigned long nr_pages)
frame_list[i] = pfn_to_mfn(pfn);
scrub_page(page);
+
+ if (!PageHighMem(page)) {
+ ret = HYPERVISOR_update_va_mapping(
+ (unsigned long)__va(pfn << PAGE_SHIFT),
+ __pte_ma(0), 0);
+ BUG_ON(ret);
+ }
+
}
/* Ensure that ballooned highmem pages don't have kmaps. */
BUG_ON(ret != nr_pages);
balloon_stats.current_pages -= nr_pages;
- totalram_pages = balloon_stats.current_pages;
spin_unlock_irqrestore(&balloon_lock, flags);
}
/* Resets the Xen limit, sets new target, and kicks off processing. */
-void balloon_set_new_target(unsigned long target)
+static void balloon_set_new_target(unsigned long target)
{
/* No need for lock. Not read-modify-write updates. */
- balloon_stats.hard_limit = ~0UL;
balloon_stats.target_pages = target;
schedule_work(&balloon_worker);
}
unsigned long pfn;
struct page *page;
- if (!is_running_on_xen())
+ if (!xen_pv_domain())
return -ENODEV;
pr_info("xen_balloon: Initialising balloon driver.\n");
balloon_stats.current_pages = min(xen_start_info->nr_pages, max_pfn);
- totalram_pages = balloon_stats.current_pages;
balloon_stats.target_pages = balloon_stats.current_pages;
balloon_stats.balloon_low = 0;
balloon_stats.balloon_high = 0;
balloon_stats.driver_pages = 0UL;
- balloon_stats.hard_limit = ~0UL;
init_timer(&balloon_timer);
balloon_timer.data = 0;
module_exit(balloon_exit);
-static void balloon_update_driver_allowance(long delta)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&balloon_lock, flags);
- balloon_stats.driver_pages += delta;
- spin_unlock_irqrestore(&balloon_lock, flags);
-}
+#define BALLOON_SHOW(name, format, args...) \
+ static ssize_t show_##name(struct sys_device *dev, \
+ struct sysdev_attribute *attr, \
+ char *buf) \
+ { \
+ return sprintf(buf, format, ##args); \
+ } \
+ static SYSDEV_ATTR(name, S_IRUGO, show_##name, NULL)
-static int dealloc_pte_fn(
- pte_t *pte, struct page *pmd_page, unsigned long addr, void *data)
-{
- unsigned long mfn = pte_mfn(*pte);
- int ret;
- struct xen_memory_reservation reservation = {
- .nr_extents = 1,
- .extent_order = 0,
- .domid = DOMID_SELF
- };
- set_xen_guest_handle(reservation.extent_start, &mfn);
- set_pte_at(&init_mm, addr, pte, __pte_ma(0ull));
- set_phys_to_machine(__pa(addr) >> PAGE_SHIFT, INVALID_P2M_ENTRY);
- ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation);
- BUG_ON(ret != 1);
- return 0;
-}
+BALLOON_SHOW(current_kb, "%lu\n", PAGES2KB(balloon_stats.current_pages));
+BALLOON_SHOW(low_kb, "%lu\n", PAGES2KB(balloon_stats.balloon_low));
+BALLOON_SHOW(high_kb, "%lu\n", PAGES2KB(balloon_stats.balloon_high));
+BALLOON_SHOW(driver_kb, "%lu\n", PAGES2KB(balloon_stats.driver_pages));
-static struct page **alloc_empty_pages_and_pagevec(int nr_pages)
+static ssize_t show_target_kb(struct sys_device *dev, struct sysdev_attribute *attr,
+ char *buf)
{
- unsigned long vaddr, flags;
- struct page *page, **pagevec;
- int i, ret;
-
- pagevec = kmalloc(sizeof(page) * nr_pages, GFP_KERNEL);
- if (pagevec == NULL)
- return NULL;
-
- for (i = 0; i < nr_pages; i++) {
- page = pagevec[i] = alloc_page(GFP_KERNEL);
- if (page == NULL)
- goto err;
-
- vaddr = (unsigned long)page_address(page);
-
- scrub_page(page);
-
- spin_lock_irqsave(&balloon_lock, flags);
-
- if (xen_feature(XENFEAT_auto_translated_physmap)) {
- unsigned long gmfn = page_to_pfn(page);
- struct xen_memory_reservation reservation = {
- .nr_extents = 1,
- .extent_order = 0,
- .domid = DOMID_SELF
- };
- set_xen_guest_handle(reservation.extent_start, &gmfn);
- ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation,
- &reservation);
- if (ret == 1)
- ret = 0; /* success */
- } else {
- ret = apply_to_page_range(&init_mm, vaddr, PAGE_SIZE,
- dealloc_pte_fn, NULL);
- }
-
- if (ret != 0) {
- spin_unlock_irqrestore(&balloon_lock, flags);
- __free_page(page);
- goto err;
- }
-
- totalram_pages = --balloon_stats.current_pages;
-
- spin_unlock_irqrestore(&balloon_lock, flags);
- }
-
- out:
- schedule_work(&balloon_worker);
- flush_tlb_all();
- return pagevec;
-
- err:
- spin_lock_irqsave(&balloon_lock, flags);
- while (--i >= 0)
- balloon_append(pagevec[i]);
- spin_unlock_irqrestore(&balloon_lock, flags);
- kfree(pagevec);
- pagevec = NULL;
- goto out;
+ return sprintf(buf, "%lu\n", PAGES2KB(balloon_stats.target_pages));
}
-static void free_empty_pages_and_pagevec(struct page **pagevec, int nr_pages)
+static ssize_t store_target_kb(struct sys_device *dev,
+ struct sysdev_attribute *attr,
+ const char *buf,
+ size_t count)
{
- unsigned long flags;
- int i;
-
- if (pagevec == NULL)
- return;
-
- spin_lock_irqsave(&balloon_lock, flags);
- for (i = 0; i < nr_pages; i++) {
- BUG_ON(page_count(pagevec[i]) != 1);
- balloon_append(pagevec[i]);
- }
- spin_unlock_irqrestore(&balloon_lock, flags);
-
- kfree(pagevec);
+ char *endchar;
+ unsigned long long target_bytes;
- schedule_work(&balloon_worker);
-}
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
-static void balloon_release_driver_page(struct page *page)
-{
- unsigned long flags;
+ target_bytes = simple_strtoull(buf, &endchar, 0) * 1024;
- spin_lock_irqsave(&balloon_lock, flags);
- balloon_append(page);
- balloon_stats.driver_pages--;
- spin_unlock_irqrestore(&balloon_lock, flags);
+ balloon_set_new_target(target_bytes >> PAGE_SHIFT);
- schedule_work(&balloon_worker);
+ return count;
}
+static SYSDEV_ATTR(target_kb, S_IRUGO | S_IWUSR,
+ show_target_kb, store_target_kb);
-#define BALLOON_SHOW(name, format, args...) \
- static ssize_t show_##name(struct sys_device *dev, \
- char *buf) \
- { \
- return sprintf(buf, format, ##args); \
- } \
- static SYSDEV_ATTR(name, S_IRUGO, show_##name, NULL)
-
-BALLOON_SHOW(current_kb, "%lu\n", PAGES2KB(balloon_stats.current_pages));
-BALLOON_SHOW(low_kb, "%lu\n", PAGES2KB(balloon_stats.balloon_low));
-BALLOON_SHOW(high_kb, "%lu\n", PAGES2KB(balloon_stats.balloon_high));
-BALLOON_SHOW(hard_limit_kb,
- (balloon_stats.hard_limit!=~0UL) ? "%lu\n" : "???\n",
- (balloon_stats.hard_limit!=~0UL) ? PAGES2KB(balloon_stats.hard_limit) : 0);
-BALLOON_SHOW(driver_kb, "%lu\n", PAGES2KB(balloon_stats.driver_pages));
-static ssize_t show_target_kb(struct sys_device *dev, char *buf)
+static ssize_t show_target(struct sys_device *dev, struct sysdev_attribute *attr,
+ char *buf)
{
- return sprintf(buf, "%lu\n", PAGES2KB(balloon_stats.target_pages));
+ return sprintf(buf, "%llu\n",
+ (unsigned long long)balloon_stats.target_pages
+ << PAGE_SHIFT);
}
-static ssize_t store_target_kb(struct sys_device *dev,
- const char *buf,
- size_t count)
+static ssize_t store_target(struct sys_device *dev,
+ struct sysdev_attribute *attr,
+ const char *buf,
+ size_t count)
{
- char memstring[64], *endchar;
+ char *endchar;
unsigned long long target_bytes;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
- if (count <= 1)
- return -EBADMSG; /* runt */
- if (count > sizeof(memstring))
- return -EFBIG; /* too long */
- strcpy(memstring, buf);
+ target_bytes = memparse(buf, &endchar);
- target_bytes = memparse(memstring, &endchar);
balloon_set_new_target(target_bytes >> PAGE_SHIFT);
return count;
}
-static SYSDEV_ATTR(target_kb, S_IRUGO | S_IWUSR,
- show_target_kb, store_target_kb);
+static SYSDEV_ATTR(target, S_IRUGO | S_IWUSR,
+ show_target, store_target);
+
static struct sysdev_attribute *balloon_attrs[] = {
&attr_target_kb,
+ &attr_target,
};
static struct attribute *balloon_info_attrs[] = {
&attr_current_kb.attr,
&attr_low_kb.attr,
&attr_high_kb.attr,
- &attr_hard_limit_kb.attr,
&attr_driver_kb.attr,
NULL
};
return error;
}
-static void unregister_balloon(struct sys_device *sysdev)
-{
- int i;
-
- sysfs_remove_group(&sysdev->kobj, &balloon_info_group);
- for (i = 0; i < ARRAY_SIZE(balloon_attrs); i++)
- sysdev_remove_file(sysdev, balloon_attrs[i]);
- sysdev_unregister(sysdev);
- sysdev_class_unregister(&balloon_sysdev_class);
-}
-
-static void balloon_sysfs_exit(void)
-{
- unregister_balloon(&balloon_sysdev);
-}
-
MODULE_LICENSE("GPL");
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff