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authorLinus Torvalds <torvalds@linux-foundation.org>2012-05-24 16:02:08 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-05-24 16:02:08 -0700
commitb5f4035adfffbcc6b478de5b8c44b618b3124aff (patch)
treee7a5f011d8aaf5c95edf933f98f25dfc8fa46837 /drivers/xen/grant-table.c
parentce004178be1bbaa292e9e6497939e2970300095a (diff)
parent68c2c39a76b094e9b2773e5846424ea674bf2c46 (diff)
downloadop-kernel-dev-b5f4035adfffbcc6b478de5b8c44b618b3124aff.zip
op-kernel-dev-b5f4035adfffbcc6b478de5b8c44b618b3124aff.tar.gz
Merge tag 'stable/for-linus-3.5-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Pull Xen updates from Konrad Rzeszutek Wilk: "Features: * Extend the APIC ops implementation and add IRQ_WORKER vector support so that 'perf' can work properly. * Fix self-ballooning code, and balloon logic when booting as initial domain. * Move array printing code to generic debugfs * Support XenBus domains. * Lazily free grants when a domain is dead/non-existent. * In M2P code use batching calls Bug-fixes: * Fix NULL dereference in allocation failure path (hvc_xen) * Fix unbinding of IRQ_WORKER vector during vCPU hot-unplug * Fix HVM guest resume - we would leak an PIRQ value instead of reusing the existing one." Fix up add-add onflicts in arch/x86/xen/enlighten.c due to addition of apic ipi interface next to the new apic_id functions. * tag 'stable/for-linus-3.5-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen: do not map the same GSI twice in PVHVM guests. hvc_xen: NULL dereference on allocation failure xen: Add selfballoning memory reservation tunable. xenbus: Add support for xenbus backend in stub domain xen/smp: unbind irqworkX when unplugging vCPUs. xen: enter/exit lazy_mmu_mode around m2p_override calls xen/acpi/sleep: Enable ACPI sleep via the __acpi_os_prepare_sleep xen: implement IRQ_WORK_VECTOR handler xen: implement apic ipi interface xen/setup: update VA mapping when releasing memory during setup xen/setup: Combine the two hypercall functions - since they are quite similar. xen/setup: Populate freed MFNs from non-RAM E820 entries and gaps to E820 RAM xen/setup: Only print "Freeing XXX-YYY pfn range: Z pages freed" if Z > 0 xen/gnttab: add deferred freeing logic debugfs: Add support to print u32 array in debugfs xen/p2m: An early bootup variant of set_phys_to_machine xen/p2m: Collapse early_alloc_p2m_middle redundant checks. xen/p2m: Allow alloc_p2m_middle to call reserve_brk depending on argument xen/p2m: Move code around to allow for better re-usage.
Diffstat (limited to 'drivers/xen/grant-table.c')
-rw-r--r--drivers/xen/grant-table.c125
1 files changed, 115 insertions, 10 deletions
diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c
index f100ce2..0bfc1ef 100644
--- a/drivers/xen/grant-table.c
+++ b/drivers/xen/grant-table.c
@@ -38,6 +38,7 @@
#include <linux/vmalloc.h>
#include <linux/uaccess.h>
#include <linux/io.h>
+#include <linux/hardirq.h>
#include <xen/xen.h>
#include <xen/interface/xen.h>
@@ -426,10 +427,8 @@ static int gnttab_end_foreign_access_ref_v1(grant_ref_t ref, int readonly)
nflags = *pflags;
do {
flags = nflags;
- if (flags & (GTF_reading|GTF_writing)) {
- printk(KERN_ALERT "WARNING: g.e. still in use!\n");
+ if (flags & (GTF_reading|GTF_writing))
return 0;
- }
} while ((nflags = sync_cmpxchg(pflags, flags, 0)) != flags);
return 1;
@@ -458,12 +457,103 @@ static int gnttab_end_foreign_access_ref_v2(grant_ref_t ref, int readonly)
return 1;
}
-int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly)
+static inline int _gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly)
{
return gnttab_interface->end_foreign_access_ref(ref, readonly);
}
+
+int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly)
+{
+ if (_gnttab_end_foreign_access_ref(ref, readonly))
+ return 1;
+ pr_warn("WARNING: g.e. %#x still in use!\n", ref);
+ return 0;
+}
EXPORT_SYMBOL_GPL(gnttab_end_foreign_access_ref);
+struct deferred_entry {
+ struct list_head list;
+ grant_ref_t ref;
+ bool ro;
+ uint16_t warn_delay;
+ struct page *page;
+};
+static LIST_HEAD(deferred_list);
+static void gnttab_handle_deferred(unsigned long);
+static DEFINE_TIMER(deferred_timer, gnttab_handle_deferred, 0, 0);
+
+static void gnttab_handle_deferred(unsigned long unused)
+{
+ unsigned int nr = 10;
+ struct deferred_entry *first = NULL;
+ unsigned long flags;
+
+ spin_lock_irqsave(&gnttab_list_lock, flags);
+ while (nr--) {
+ struct deferred_entry *entry
+ = list_first_entry(&deferred_list,
+ struct deferred_entry, list);
+
+ if (entry == first)
+ break;
+ list_del(&entry->list);
+ spin_unlock_irqrestore(&gnttab_list_lock, flags);
+ if (_gnttab_end_foreign_access_ref(entry->ref, entry->ro)) {
+ put_free_entry(entry->ref);
+ if (entry->page) {
+ pr_debug("freeing g.e. %#x (pfn %#lx)\n",
+ entry->ref, page_to_pfn(entry->page));
+ __free_page(entry->page);
+ } else
+ pr_info("freeing g.e. %#x\n", entry->ref);
+ kfree(entry);
+ entry = NULL;
+ } else {
+ if (!--entry->warn_delay)
+ pr_info("g.e. %#x still pending\n",
+ entry->ref);
+ if (!first)
+ first = entry;
+ }
+ spin_lock_irqsave(&gnttab_list_lock, flags);
+ if (entry)
+ list_add_tail(&entry->list, &deferred_list);
+ else if (list_empty(&deferred_list))
+ break;
+ }
+ if (!list_empty(&deferred_list) && !timer_pending(&deferred_timer)) {
+ deferred_timer.expires = jiffies + HZ;
+ add_timer(&deferred_timer);
+ }
+ spin_unlock_irqrestore(&gnttab_list_lock, flags);
+}
+
+static void gnttab_add_deferred(grant_ref_t ref, bool readonly,
+ struct page *page)
+{
+ struct deferred_entry *entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
+ const char *what = KERN_WARNING "leaking";
+
+ if (entry) {
+ unsigned long flags;
+
+ entry->ref = ref;
+ entry->ro = readonly;
+ entry->page = page;
+ entry->warn_delay = 60;
+ spin_lock_irqsave(&gnttab_list_lock, flags);
+ list_add_tail(&entry->list, &deferred_list);
+ if (!timer_pending(&deferred_timer)) {
+ deferred_timer.expires = jiffies + HZ;
+ add_timer(&deferred_timer);
+ }
+ spin_unlock_irqrestore(&gnttab_list_lock, flags);
+ what = KERN_DEBUG "deferring";
+ }
+ printk("%s g.e. %#x (pfn %#lx)\n",
+ what, ref, page ? page_to_pfn(page) : -1);
+}
+
void gnttab_end_foreign_access(grant_ref_t ref, int readonly,
unsigned long page)
{
@@ -471,12 +561,9 @@ void gnttab_end_foreign_access(grant_ref_t ref, int readonly,
put_free_entry(ref);
if (page != 0)
free_page(page);
- } else {
- /* XXX This needs to be fixed so that the ref and page are
- placed on a list to be freed up later. */
- printk(KERN_WARNING
- "WARNING: leaking g.e. and page still in use!\n");
- }
+ } else
+ gnttab_add_deferred(ref, readonly,
+ page ? virt_to_page(page) : NULL);
}
EXPORT_SYMBOL_GPL(gnttab_end_foreign_access);
@@ -741,6 +828,7 @@ int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
struct page **pages, unsigned int count)
{
int i, ret;
+ bool lazy = false;
pte_t *pte;
unsigned long mfn;
@@ -751,6 +839,11 @@ int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
if (xen_feature(XENFEAT_auto_translated_physmap))
return ret;
+ if (!in_interrupt() && paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE) {
+ arch_enter_lazy_mmu_mode();
+ lazy = true;
+ }
+
for (i = 0; i < count; i++) {
/* Do not add to override if the map failed. */
if (map_ops[i].status)
@@ -769,6 +862,9 @@ int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
return ret;
}
+ if (lazy)
+ arch_leave_lazy_mmu_mode();
+
return ret;
}
EXPORT_SYMBOL_GPL(gnttab_map_refs);
@@ -777,6 +873,7 @@ int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops,
struct page **pages, unsigned int count, bool clear_pte)
{
int i, ret;
+ bool lazy = false;
ret = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, unmap_ops, count);
if (ret)
@@ -785,12 +882,20 @@ int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops,
if (xen_feature(XENFEAT_auto_translated_physmap))
return ret;
+ if (!in_interrupt() && paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE) {
+ arch_enter_lazy_mmu_mode();
+ lazy = true;
+ }
+
for (i = 0; i < count; i++) {
ret = m2p_remove_override(pages[i], clear_pte);
if (ret)
return ret;
}
+ if (lazy)
+ arch_leave_lazy_mmu_mode();
+
return ret;
}
EXPORT_SYMBOL_GPL(gnttab_unmap_refs);
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