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Diffstat (limited to 'drivers/xen/balloon.c')
-rw-r--r--drivers/xen/balloon.c175
1 files changed, 15 insertions, 160 deletions
diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c
index 2e15da5459cf..8c83abc73400 100644
--- a/drivers/xen/balloon.c
+++ b/drivers/xen/balloon.c
@@ -53,7 +53,6 @@
53#include <asm/tlb.h> 53#include <asm/tlb.h>
54 54
55#include <xen/interface/memory.h> 55#include <xen/interface/memory.h>
56#include <xen/balloon.h>
57#include <xen/xenbus.h> 56#include <xen/xenbus.h>
58#include <xen/features.h> 57#include <xen/features.h>
59#include <xen/page.h> 58#include <xen/page.h>
@@ -226,9 +225,8 @@ static int increase_reservation(unsigned long nr_pages)
226 } 225 }
227 226
228 set_xen_guest_handle(reservation.extent_start, frame_list); 227 set_xen_guest_handle(reservation.extent_start, frame_list);
229 reservation.nr_extents = nr_pages; 228 reservation.nr_extents = nr_pages;
230 rc = HYPERVISOR_memory_op( 229 rc = HYPERVISOR_memory_op(XENMEM_populate_physmap, &reservation);
231 XENMEM_populate_physmap, &reservation);
232 if (rc < nr_pages) { 230 if (rc < nr_pages) {
233 if (rc > 0) { 231 if (rc > 0) {
234 int ret; 232 int ret;
@@ -236,7 +234,7 @@ static int increase_reservation(unsigned long nr_pages)
236 /* We hit the Xen hard limit: reprobe. */ 234 /* We hit the Xen hard limit: reprobe. */
237 reservation.nr_extents = rc; 235 reservation.nr_extents = rc;
238 ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation, 236 ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation,
239 &reservation); 237 &reservation);
240 BUG_ON(ret != rc); 238 BUG_ON(ret != rc);
241 } 239 }
242 if (rc >= 0) 240 if (rc >= 0)
@@ -420,7 +418,7 @@ static int __init balloon_init(void)
420 unsigned long pfn; 418 unsigned long pfn;
421 struct page *page; 419 struct page *page;
422 420
423 if (!is_running_on_xen()) 421 if (!xen_pv_domain())
424 return -ENODEV; 422 return -ENODEV;
425 423
426 pr_info("xen_balloon: Initialising balloon driver.\n"); 424 pr_info("xen_balloon: Initialising balloon driver.\n");
@@ -464,136 +462,13 @@ static void balloon_exit(void)
464 462
465module_exit(balloon_exit); 463module_exit(balloon_exit);
466 464
467static void balloon_update_driver_allowance(long delta) 465#define BALLOON_SHOW(name, format, args...) \
468{ 466 static ssize_t show_##name(struct sys_device *dev, \
469 unsigned long flags; 467 struct sysdev_attribute *attr, \
470 468 char *buf) \
471 spin_lock_irqsave(&balloon_lock, flags); 469 { \
472 balloon_stats.driver_pages += delta; 470 return sprintf(buf, format, ##args); \
473 spin_unlock_irqrestore(&balloon_lock, flags); 471 } \
474}
475
476static int dealloc_pte_fn(
477 pte_t *pte, struct page *pmd_page, unsigned long addr, void *data)
478{
479 unsigned long mfn = pte_mfn(*pte);
480 int ret;
481 struct xen_memory_reservation reservation = {
482 .nr_extents = 1,
483 .extent_order = 0,
484 .domid = DOMID_SELF
485 };
486 set_xen_guest_handle(reservation.extent_start, &mfn);
487 set_pte_at(&init_mm, addr, pte, __pte_ma(0ull));
488 set_phys_to_machine(__pa(addr) >> PAGE_SHIFT, INVALID_P2M_ENTRY);
489 ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation);
490 BUG_ON(ret != 1);
491 return 0;
492}
493
494static struct page **alloc_empty_pages_and_pagevec(int nr_pages)
495{
496 unsigned long vaddr, flags;
497 struct page *page, **pagevec;
498 int i, ret;
499
500 pagevec = kmalloc(sizeof(page) * nr_pages, GFP_KERNEL);
501 if (pagevec == NULL)
502 return NULL;
503
504 for (i = 0; i < nr_pages; i++) {
505 page = pagevec[i] = alloc_page(GFP_KERNEL);
506 if (page == NULL)
507 goto err;
508
509 vaddr = (unsigned long)page_address(page);
510
511 scrub_page(page);
512
513 spin_lock_irqsave(&balloon_lock, flags);
514
515 if (xen_feature(XENFEAT_auto_translated_physmap)) {
516 unsigned long gmfn = page_to_pfn(page);
517 struct xen_memory_reservation reservation = {
518 .nr_extents = 1,
519 .extent_order = 0,
520 .domid = DOMID_SELF
521 };
522 set_xen_guest_handle(reservation.extent_start, &gmfn);
523 ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation,
524 &reservation);
525 if (ret == 1)
526 ret = 0; /* success */
527 } else {
528 ret = apply_to_page_range(&init_mm, vaddr, PAGE_SIZE,
529 dealloc_pte_fn, NULL);
530 }
531
532 if (ret != 0) {
533 spin_unlock_irqrestore(&balloon_lock, flags);
534 __free_page(page);
535 goto err;
536 }
537
538 totalram_pages = --balloon_stats.current_pages;
539
540 spin_unlock_irqrestore(&balloon_lock, flags);
541 }
542
543 out:
544 schedule_work(&balloon_worker);
545 flush_tlb_all();
546 return pagevec;
547
548 err:
549 spin_lock_irqsave(&balloon_lock, flags);
550 while (--i >= 0)
551 balloon_append(pagevec[i]);
552 spin_unlock_irqrestore(&balloon_lock, flags);
553 kfree(pagevec);
554 pagevec = NULL;
555 goto out;
556}
557
558static void free_empty_pages_and_pagevec(struct page **pagevec, int nr_pages)
559{
560 unsigned long flags;
561 int i;
562
563 if (pagevec == NULL)
564 return;
565
566 spin_lock_irqsave(&balloon_lock, flags);
567 for (i = 0; i < nr_pages; i++) {
568 BUG_ON(page_count(pagevec[i]) != 1);
569 balloon_append(pagevec[i]);
570 }
571 spin_unlock_irqrestore(&balloon_lock, flags);
572
573 kfree(pagevec);
574
575 schedule_work(&balloon_worker);
576}
577
578static void balloon_release_driver_page(struct page *page)
579{
580 unsigned long flags;
581
582 spin_lock_irqsave(&balloon_lock, flags);
583 balloon_append(page);
584 balloon_stats.driver_pages--;
585 spin_unlock_irqrestore(&balloon_lock, flags);
586
587 schedule_work(&balloon_worker);
588}
589
590
591#define BALLOON_SHOW(name, format, args...) \
592 static ssize_t show_##name(struct sys_device *dev, \
593 char *buf) \
594 { \
595 return sprintf(buf, format, ##args); \
596 } \
597 static SYSDEV_ATTR(name, S_IRUGO, show_##name, NULL) 472 static SYSDEV_ATTR(name, S_IRUGO, show_##name, NULL)
598 473
599BALLOON_SHOW(current_kb, "%lu\n", PAGES2KB(balloon_stats.current_pages)); 474BALLOON_SHOW(current_kb, "%lu\n", PAGES2KB(balloon_stats.current_pages));
@@ -604,7 +479,8 @@ BALLOON_SHOW(hard_limit_kb,
604 (balloon_stats.hard_limit!=~0UL) ? PAGES2KB(balloon_stats.hard_limit) : 0); 479 (balloon_stats.hard_limit!=~0UL) ? PAGES2KB(balloon_stats.hard_limit) : 0);
605BALLOON_SHOW(driver_kb, "%lu\n", PAGES2KB(balloon_stats.driver_pages)); 480BALLOON_SHOW(driver_kb, "%lu\n", PAGES2KB(balloon_stats.driver_pages));
606 481
607static ssize_t show_target_kb(struct sys_device *dev, char *buf) 482static ssize_t show_target_kb(struct sys_device *dev, struct sysdev_attribute *attr,
483 char *buf)
608{ 484{
609 return sprintf(buf, "%lu\n", PAGES2KB(balloon_stats.target_pages)); 485 return sprintf(buf, "%lu\n", PAGES2KB(balloon_stats.target_pages));
610} 486}
@@ -614,19 +490,14 @@ static ssize_t store_target_kb(struct sys_device *dev,
614 const char *buf, 490 const char *buf,
615 size_t count) 491 size_t count)
616{ 492{
617 char memstring[64], *endchar; 493 char *endchar;
618 unsigned long long target_bytes; 494 unsigned long long target_bytes;
619 495
620 if (!capable(CAP_SYS_ADMIN)) 496 if (!capable(CAP_SYS_ADMIN))
621 return -EPERM; 497 return -EPERM;
622 498
623 if (count <= 1) 499 target_bytes = memparse(buf, &endchar);
624 return -EBADMSG; /* runt */
625 if (count > sizeof(memstring))
626 return -EFBIG; /* too long */
627 strcpy(memstring, buf);
628 500
629 target_bytes = memparse(memstring, &endchar);
630 balloon_set_new_target(target_bytes >> PAGE_SHIFT); 501 balloon_set_new_target(target_bytes >> PAGE_SHIFT);
631 502
632 return count; 503 return count;
@@ -694,20 +565,4 @@ static int register_balloon(struct sys_device *sysdev)
694 return error; 565 return error;
695} 566}
696 567
697static void unregister_balloon(struct sys_device *sysdev)
698{
699 int i;
700
701 sysfs_remove_group(&sysdev->kobj, &balloon_info_group);
702 for (i = 0; i < ARRAY_SIZE(balloon_attrs); i++)
703 sysdev_remove_file(sysdev, balloon_attrs[i]);
704 sysdev_unregister(sysdev);
705 sysdev_class_unregister(&balloon_sysdev_class);
706}
707
708static void balloon_sysfs_exit(void)
709{
710 unregister_balloon(&balloon_sysdev);
711}
712
713MODULE_LICENSE("GPL"); 568MODULE_LICENSE("GPL");