diff options
Diffstat (limited to 'usr/src/uts/i86pc/vm/i86_mmu.c')
| -rw-r--r-- | usr/src/uts/i86pc/vm/i86_mmu.c | 117 |
1 files changed, 111 insertions, 6 deletions
diff --git a/usr/src/uts/i86pc/vm/i86_mmu.c b/usr/src/uts/i86pc/vm/i86_mmu.c index 7bf91af9b5..069411ae23 100644 --- a/usr/src/uts/i86pc/vm/i86_mmu.c +++ b/usr/src/uts/i86pc/vm/i86_mmu.c @@ -59,6 +59,10 @@ #include <sys/bootinfo.h> #include <vm/kboot_mmu.h> +#ifdef __xpv +#include <sys/hypervisor.h> +#endif + caddr_t i86devmap(pfn_t pf, pgcnt_t pgcnt, uint_t prot) { @@ -195,6 +199,8 @@ hat_kmap_init(uintptr_t base, size_t len) /* * We have to map in an area that matches an entire page table. + * The PTEs are large page aligned to avoid spurious pagefaults + * on the hypervisor. */ map_addr = base & LEVEL_MASK(1); map_eaddr = (base + len + LEVEL_SIZE(1) - 1) & LEVEL_MASK(1); @@ -224,7 +230,11 @@ hat_kmap_init(uintptr_t base, size_t len) hat_devload(kas.a_hat, ptes + i * MMU_PAGESIZE, MMU_PAGESIZE, ht->ht_pfn, +#ifdef __xpv + PROT_READ | HAT_NOSYNC | HAT_UNORDERED_OK, +#else PROT_READ | PROT_WRITE | HAT_NOSYNC | HAT_UNORDERED_OK, +#endif HAT_LOAD | HAT_LOAD_NOCONSIST); } @@ -239,6 +249,55 @@ hat_kmap_init(uintptr_t base, size_t len) extern caddr_t kpm_vbase; extern size_t kpm_size; +#ifdef __xpv +/* + * Create the initial segkpm mappings for the hypervisor. To avoid having + * to deal with page tables being read only, we make all mappings + * read only at first. + */ +static void +xen_kpm_create(paddr_t paddr, level_t lvl) +{ + ulong_t pg_off; + + for (pg_off = 0; pg_off < LEVEL_SIZE(lvl); pg_off += MMU_PAGESIZE) { + kbm_map((uintptr_t)kpm_vbase + paddr, (paddr_t)0, 0, 1); + kbm_read_only((uintptr_t)kpm_vbase + paddr + pg_off, + paddr + pg_off); + } +} + +/* + * Try to make all kpm mappings writable. Failures are ok, as those + * are just pagetable, GDT, etc. pages. + */ +static void +xen_kpm_finish_init(void) +{ + pfn_t gdtpfn = mmu_btop(CPU->cpu_m.mcpu_gdtpa); + pfn_t pfn; + page_t *pp; + + for (pfn = 0; pfn < mfn_count; ++pfn) { + /* + * skip gdt + */ + if (pfn == gdtpfn) + continue; + + /* + * p_index is a hint that this is a pagetable + */ + pp = page_numtopp_nolock(pfn); + if (pp && pp->p_index) { + pp->p_index = 0; + continue; + } + (void) xen_kpm_page(pfn, PT_VALID | PT_WRITABLE); + } +} +#endif + /* * Routine to pre-allocate data structures for hat_kern_setup(). It computes * how many pagetables it needs by walking the boot loader's page tables. @@ -263,11 +322,13 @@ hat_kern_alloc( level_t lpagel = mmu.max_page_level; uint64_t paddr; int64_t psize; - + int nwindows; if (kpm_size > 0) { /* - * Create the kpm page tables. + * Create the kpm page tables. When running on the + * hypervisor these are made read/only at first. + * Later we'll add write permission where possible. */ for (pmem = phys_install; pmem; pmem = pmem->next) { paddr = pmem->address; @@ -278,20 +339,45 @@ hat_kern_alloc( l = lpagel; else l = 0; +#if defined(__xpv) + /* + * Create read/only mappings to avoid + * conflicting with pagetable usage + */ + xen_kpm_create(paddr, l); +#else kbm_map((uintptr_t)kpm_vbase + paddr, paddr, l, 1); +#endif paddr += LEVEL_SIZE(l); psize -= LEVEL_SIZE(l); } } - } else { + } + + /* + * If this machine doesn't have a kpm segment, we need to allocate + * a small number of 'windows' which can be used to map pagetables. + */ + nwindows = (kpm_size == 0) ? 2 * NCPU : 0; + +#if defined(__xpv) + /* + * On a hypervisor, these windows are also used by the xpv_panic + * code, where we need one window for each level of the pagetable + * hierarchy. + */ + nwindows = MAX(nwindows, mmu.max_level); +#endif + + if (nwindows != 0) { /* * Create the page windows and 1 page of VA in * which we map the PTEs of those windows. */ - mmu.pwin_base = vmem_xalloc(heap_arena, 2 * NCPU * MMU_PAGESIZE, + mmu.pwin_base = vmem_xalloc(heap_arena, nwindows * MMU_PAGESIZE, LEVEL_SIZE(1), 0, 0, NULL, NULL, VM_SLEEP); - ASSERT(NCPU * 2 <= MMU_PAGESIZE / mmu.pte_size); + ASSERT(nwindows <= MMU_PAGESIZE / mmu.pte_size); mmu.pwin_pte_va = vmem_xalloc(heap_arena, MMU_PAGESIZE, MMU_PAGESIZE, 0, 0, NULL, NULL, VM_SLEEP); @@ -303,7 +389,12 @@ hat_kern_alloc( ASSERT(paddr != 0); ASSERT((paddr & MMU_PAGEOFFSET) == 0); mmu.pwin_pte_pa = paddr; +#ifdef __xpv + (void) find_pte((uintptr_t)mmu.pwin_pte_va, NULL, 0, 0); + kbm_read_only((uintptr_t)mmu.pwin_pte_va, mmu.pwin_pte_pa); +#else kbm_map((uintptr_t)mmu.pwin_pte_va, mmu.pwin_pte_pa, 0, 1); +#endif } /* @@ -391,13 +482,27 @@ hat_kern_setup(void) /* * Attach htables to the existing pagetables */ + /* BEGIN CSTYLED */ htable_attach(kas.a_hat, 0, mmu.max_level, NULL, +#ifdef __xpv + mmu_btop(xen_info->pt_base - ONE_GIG)); +#else mmu_btop(getcr3())); +#endif + /* END CSTYLED */ -#if defined(__i386) +#if defined(__i386) && !defined(__xpv) CPU->cpu_tss->tss_cr3 = dftss0.tss_cr3 = getcr3(); #endif /* __i386 */ +#if defined(__xpv) && defined(__amd64) + /* + * Try to make the kpm mappings r/w. Failures here are OK, as + * it's probably just a pagetable + */ + xen_kpm_finish_init(); +#endif + /* * The kernel HAT is now officially open for business. */ |