diff options
Diffstat (limited to 'arch/x86/xen/enlighten.c')
| -rw-r--r-- | arch/x86/xen/enlighten.c | 99 |
1 files changed, 84 insertions, 15 deletions
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index c13698faae5..48f1a7eca8b 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -46,7 +46,6 @@ #include <asm/pgtable.h> #include <asm/tlbflush.h> #include <asm/reboot.h> -#include <asm/pgalloc.h> #include "xen-ops.h" #include "mmu.h" @@ -711,29 +710,57 @@ static void set_current_cr3(void *v) x86_write_percpu(xen_current_cr3, (unsigned long)v); } -static void xen_write_cr3(unsigned long cr3) +static void __xen_write_cr3(bool kernel, unsigned long cr3) { struct mmuext_op *op; struct multicall_space mcs; - unsigned long mfn = pfn_to_mfn(PFN_DOWN(cr3)); + unsigned long mfn; - BUG_ON(preemptible()); + if (cr3) + mfn = pfn_to_mfn(PFN_DOWN(cr3)); + else + mfn = 0; - mcs = xen_mc_entry(sizeof(*op)); /* disables interrupts */ + WARN_ON(mfn == 0 && kernel); - /* Update while interrupts are disabled, so its atomic with - respect to ipis */ - x86_write_percpu(xen_cr3, cr3); + mcs = __xen_mc_entry(sizeof(*op)); op = mcs.args; - op->cmd = MMUEXT_NEW_BASEPTR; + op->cmd = kernel ? MMUEXT_NEW_BASEPTR : MMUEXT_NEW_USER_BASEPTR; op->arg1.mfn = mfn; MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF); - /* Update xen_update_cr3 once the batch has actually - been submitted. */ - xen_mc_callback(set_current_cr3, (void *)cr3); + if (kernel) { + x86_write_percpu(xen_cr3, cr3); + + /* Update xen_current_cr3 once the batch has actually + been submitted. */ + xen_mc_callback(set_current_cr3, (void *)cr3); + } +} + +static void xen_write_cr3(unsigned long cr3) +{ + BUG_ON(preemptible()); + + xen_mc_batch(); /* disables interrupts */ + + /* Update while interrupts are disabled, so its atomic with + respect to ipis */ + x86_write_percpu(xen_cr3, cr3); + + __xen_write_cr3(true, cr3); + +#ifdef CONFIG_X86_64 + { + pgd_t *user_pgd = xen_get_user_pgd(__va(cr3)); + if (user_pgd) + __xen_write_cr3(false, __pa(user_pgd)); + else + __xen_write_cr3(false, 0); + } +#endif xen_mc_issue(PARAVIRT_LAZY_CPU); /* interrupts restored */ } @@ -794,6 +821,40 @@ static void xen_alloc_pmd(struct mm_struct *mm, u32 pfn) xen_alloc_ptpage(mm, pfn, PT_PMD); } +static int xen_pgd_alloc(struct mm_struct *mm) +{ + pgd_t *pgd = mm->pgd; + int ret = 0; + + BUG_ON(PagePinned(virt_to_page(pgd))); + +#ifdef CONFIG_X86_64 + { + struct page *page = virt_to_page(pgd); + + BUG_ON(page->private != 0); + + page->private = __get_free_page(GFP_KERNEL | __GFP_ZERO); + if (page->private == 0) + ret = -ENOMEM; + + BUG_ON(PagePinned(virt_to_page(xen_get_user_pgd(pgd)))); + } +#endif + + return ret; +} + +static void xen_pgd_free(struct mm_struct *mm, pgd_t *pgd) +{ +#ifdef CONFIG_X86_64 + pgd_t *user_pgd = xen_get_user_pgd(pgd); + + if (user_pgd) + free_page((unsigned long)user_pgd); +#endif +} + /* This should never happen until we're OK to use struct page */ static void xen_release_ptpage(u32 pfn, unsigned level) { @@ -1168,8 +1229,8 @@ static const struct pv_mmu_ops xen_mmu_ops __initdata = { .pte_update = paravirt_nop, .pte_update_defer = paravirt_nop, - .pgd_alloc = __paravirt_pgd_alloc, - .pgd_free = paravirt_nop, + .pgd_alloc = xen_pgd_alloc, + .pgd_free = xen_pgd_free, .alloc_pte = xen_alloc_pte_init, .release_pte = xen_release_pte_init, @@ -1480,7 +1541,15 @@ static __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pf /* Switch over */ pgd = init_level4_pgt; - xen_write_cr3(__pa(pgd)); + + /* + * At this stage there can be no user pgd, and no page + * structure to attach it to, so make sure we just set kernel + * pgd. + */ + xen_mc_batch(); + __xen_write_cr3(true, __pa(pgd)); + xen_mc_issue(PARAVIRT_LAZY_CPU); reserve_early(__pa(xen_start_info->pt_base), __pa(xen_start_info->pt_base + |