summaryrefslogtreecommitdiffstats
path: root/arch/x86/xen/mmu.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/xen/mmu.c')
-rw-r--r--arch/x86/xen/mmu.c113
1 files changed, 82 insertions, 31 deletions
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 72f08ab43a4d..b2e32f9d0071 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -303,7 +303,12 @@ pgd_t xen_make_pgd(unsigned long pgd)
}
#endif /* CONFIG_X86_PAE */
-
+enum pt_level {
+ PT_PGD,
+ PT_PUD,
+ PT_PMD,
+ PT_PTE
+};
/*
(Yet another) pagetable walker. This one is intended for pinning a
@@ -315,7 +320,7 @@ pgd_t xen_make_pgd(unsigned long pgd)
FIXADDR_TOP. But the important bit is that we don't pin beyond
there, because then we start getting into Xen's ptes.
*/
-static int pgd_walk(pgd_t *pgd_base, int (*func)(struct page *, unsigned),
+static int pgd_walk(pgd_t *pgd_base, int (*func)(struct page *, enum pt_level),
unsigned long limit)
{
pgd_t *pgd = pgd_base;
@@ -340,7 +345,7 @@ static int pgd_walk(pgd_t *pgd_base, int (*func)(struct page *, unsigned),
pud = pud_offset(pgd, 0);
if (PTRS_PER_PUD > 1) /* not folded */
- flush |= (*func)(virt_to_page(pud), 0);
+ flush |= (*func)(virt_to_page(pud), PT_PUD);
for (; addr != pud_limit; pud++, addr = pud_next) {
pmd_t *pmd;
@@ -359,7 +364,7 @@ static int pgd_walk(pgd_t *pgd_base, int (*func)(struct page *, unsigned),
pmd = pmd_offset(pud, 0);
if (PTRS_PER_PMD > 1) /* not folded */
- flush |= (*func)(virt_to_page(pmd), 0);
+ flush |= (*func)(virt_to_page(pmd), PT_PMD);
for (; addr != pmd_limit; pmd++) {
addr += (PAGE_SIZE * PTRS_PER_PTE);
@@ -371,17 +376,47 @@ static int pgd_walk(pgd_t *pgd_base, int (*func)(struct page *, unsigned),
if (pmd_none(*pmd))
continue;
- flush |= (*func)(pmd_page(*pmd), 0);
+ flush |= (*func)(pmd_page(*pmd), PT_PTE);
}
}
}
- flush |= (*func)(virt_to_page(pgd_base), UVMF_TLB_FLUSH);
+ flush |= (*func)(virt_to_page(pgd_base), PT_PGD);
return flush;
}
-static int pin_page(struct page *page, unsigned flags)
+static spinlock_t *lock_pte(struct page *page)
+{
+ spinlock_t *ptl = NULL;
+
+#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
+ ptl = __pte_lockptr(page);
+ spin_lock(ptl);
+#endif
+
+ return ptl;
+}
+
+static void do_unlock(void *v)
+{
+ spinlock_t *ptl = v;
+ spin_unlock(ptl);
+}
+
+static void xen_do_pin(unsigned level, unsigned long pfn)
+{
+ struct mmuext_op *op;
+ struct multicall_space mcs;
+
+ mcs = __xen_mc_entry(sizeof(*op));
+ op = mcs.args;
+ op->cmd = level;
+ op->arg1.mfn = pfn_to_mfn(pfn);
+ MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
+}
+
+static int pin_page(struct page *page, enum pt_level level)
{
unsigned pgfl = test_and_set_bit(PG_pinned, &page->flags);
int flush;
@@ -396,12 +431,26 @@ static int pin_page(struct page *page, unsigned flags)
void *pt = lowmem_page_address(page);
unsigned long pfn = page_to_pfn(page);
struct multicall_space mcs = __xen_mc_entry(0);
+ spinlock_t *ptl;
flush = 0;
+ ptl = NULL;
+ if (level == PT_PTE)
+ ptl = lock_pte(page);
+
MULTI_update_va_mapping(mcs.mc, (unsigned long)pt,
pfn_pte(pfn, PAGE_KERNEL_RO),
- flags);
+ level == PT_PGD ? UVMF_TLB_FLUSH : 0);
+
+ if (level == PT_PTE)
+ xen_do_pin(MMUEXT_PIN_L1_TABLE, pfn);
+
+ if (ptl) {
+ /* Queue a deferred unlock for when this batch
+ is completed. */
+ xen_mc_callback(do_unlock, ptl);
+ }
}
return flush;
@@ -412,8 +461,7 @@ static int pin_page(struct page *page, unsigned flags)
read-only, and can be pinned. */
void xen_pgd_pin(pgd_t *pgd)
{
- struct multicall_space mcs;
- struct mmuext_op *op;
+ unsigned level;
xen_mc_batch();
@@ -424,16 +472,13 @@ void xen_pgd_pin(pgd_t *pgd)
xen_mc_batch();
}
- mcs = __xen_mc_entry(sizeof(*op));
- op = mcs.args;
-
#ifdef CONFIG_X86_PAE
- op->cmd = MMUEXT_PIN_L3_TABLE;
+ level = MMUEXT_PIN_L3_TABLE;
#else
- op->cmd = MMUEXT_PIN_L2_TABLE;
+ level = MMUEXT_PIN_L2_TABLE;
#endif
- op->arg1.mfn = pfn_to_mfn(PFN_DOWN(__pa(pgd)));
- MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
+
+ xen_do_pin(level, PFN_DOWN(__pa(pgd)));
xen_mc_issue(0);
}
@@ -441,7 +486,7 @@ void xen_pgd_pin(pgd_t *pgd)
/* The init_mm pagetable is really pinned as soon as its created, but
that's before we have page structures to store the bits. So do all
the book-keeping now. */
-static __init int mark_pinned(struct page *page, unsigned flags)
+static __init int mark_pinned(struct page *page, enum pt_level level)
{
SetPagePinned(page);
return 0;
@@ -452,18 +497,32 @@ void __init xen_mark_init_mm_pinned(void)
pgd_walk(init_mm.pgd, mark_pinned, FIXADDR_TOP);
}
-static int unpin_page(struct page *page, unsigned flags)
+static int unpin_page(struct page *page, enum pt_level level)
{
unsigned pgfl = test_and_clear_bit(PG_pinned, &page->flags);
if (pgfl && !PageHighMem(page)) {
void *pt = lowmem_page_address(page);
unsigned long pfn = page_to_pfn(page);
- struct multicall_space mcs = __xen_mc_entry(0);
+ spinlock_t *ptl = NULL;
+ struct multicall_space mcs;
+
+ if (level == PT_PTE) {
+ ptl = lock_pte(page);
+
+ xen_do_pin(MMUEXT_UNPIN_TABLE, pfn);
+ }
+
+ mcs = __xen_mc_entry(0);
MULTI_update_va_mapping(mcs.mc, (unsigned long)pt,
pfn_pte(pfn, PAGE_KERNEL),
- flags);
+ level == PT_PGD ? UVMF_TLB_FLUSH : 0);
+
+ if (ptl) {
+ /* unlock when batch completed */
+ xen_mc_callback(do_unlock, ptl);
+ }
}
return 0; /* never need to flush on unpin */
@@ -472,18 +531,9 @@ static int unpin_page(struct page *page, unsigned flags)
/* Release a pagetables pages back as normal RW */
static void xen_pgd_unpin(pgd_t *pgd)
{
- struct mmuext_op *op;
- struct multicall_space mcs;
-
xen_mc_batch();
- mcs = __xen_mc_entry(sizeof(*op));
-
- op = mcs.args;
- op->cmd = MMUEXT_UNPIN_TABLE;
- op->arg1.mfn = pfn_to_mfn(PFN_DOWN(__pa(pgd)));
-
- MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
+ xen_do_pin(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(pgd)));
pgd_walk(pgd, unpin_page, TASK_SIZE);
@@ -585,5 +635,6 @@ void xen_exit_mmap(struct mm_struct *mm)
/* pgd may not be pinned in the error exit path of execve */
if (PagePinned(virt_to_page(mm->pgd)))
xen_pgd_unpin(mm->pgd);
+
spin_unlock(&mm->page_table_lock);
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-14 00:02:38 +0000