diff options
Diffstat (limited to 'arch/x86/xen/mmu.c')
| -rw-r--r-- | arch/x86/xen/mmu.c | 237 |
1 files changed, 237 insertions, 0 deletions
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c new file mode 100644 index 000000000..96fc2f0fd --- /dev/null +++ b/arch/x86/xen/mmu.c @@ -0,0 +1,237 @@ +#include <linux/pfn.h> +#include <asm/xen/page.h> +#include <asm/xen/hypercall.h> +#include <xen/interface/memory.h> + +#include "multicalls.h" +#include "mmu.h" + +/* + * Protects atomic reservation decrease/increase against concurrent increases. + * Also protects non-atomic updates of current_pages and balloon lists. + */ +DEFINE_SPINLOCK(xen_reservation_lock); + +unsigned long arbitrary_virt_to_mfn(void *vaddr) +{ + xmaddr_t maddr = arbitrary_virt_to_machine(vaddr); + + return PFN_DOWN(maddr.maddr); +} + +xmaddr_t arbitrary_virt_to_machine(void *vaddr) +{ + unsigned long address = (unsigned long)vaddr; + unsigned int level; + pte_t *pte; + unsigned offset; + + /* + * if the PFN is in the linear mapped vaddr range, we can just use + * the (quick) virt_to_machine() p2m lookup + */ + if (virt_addr_valid(vaddr)) + return virt_to_machine(vaddr); + + /* otherwise we have to do a (slower) full page-table walk */ + + pte = lookup_address(address, &level); + BUG_ON(pte == NULL); + offset = address & ~PAGE_MASK; + return XMADDR(((phys_addr_t)pte_mfn(*pte) << PAGE_SHIFT) + offset); +} +EXPORT_SYMBOL_GPL(arbitrary_virt_to_machine); + +static noinline void xen_flush_tlb_all(void) +{ + struct mmuext_op *op; + struct multicall_space mcs; + + preempt_disable(); + + mcs = xen_mc_entry(sizeof(*op)); + + op = mcs.args; + op->cmd = MMUEXT_TLB_FLUSH_ALL; + MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF); + + xen_mc_issue(PARAVIRT_LAZY_MMU); + + preempt_enable(); +} + +#define REMAP_BATCH_SIZE 16 + +struct remap_data { + xen_pfn_t *pfn; + bool contiguous; + bool no_translate; + pgprot_t prot; + struct mmu_update *mmu_update; +}; + +static int remap_area_pfn_pte_fn(pte_t *ptep, pgtable_t token, + unsigned long addr, void *data) +{ + struct remap_data *rmd = data; + pte_t pte = pte_mkspecial(mfn_pte(*rmd->pfn, rmd->prot)); + + /* + * If we have a contiguous range, just update the pfn itself, + * else update pointer to be "next pfn". + */ + if (rmd->contiguous) + (*rmd->pfn)++; + else + rmd->pfn++; + + rmd->mmu_update->ptr = virt_to_machine(ptep).maddr; + rmd->mmu_update->ptr |= rmd->no_translate ? + MMU_PT_UPDATE_NO_TRANSLATE : + MMU_NORMAL_PT_UPDATE; + rmd->mmu_update->val = pte_val_ma(pte); + rmd->mmu_update++; + + return 0; +} + +static int do_remap_pfn(struct vm_area_struct *vma, + unsigned long addr, + xen_pfn_t *pfn, int nr, + int *err_ptr, pgprot_t prot, + unsigned int domid, + bool no_translate, + struct page **pages) +{ + int err = 0; + struct remap_data rmd; + struct mmu_update mmu_update[REMAP_BATCH_SIZE]; + unsigned long range; + int mapped = 0; + + BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_IO)) == (VM_PFNMAP | VM_IO))); + + rmd.pfn = pfn; + rmd.prot = prot; + /* + * We use the err_ptr to indicate if there we are doing a contiguous + * mapping or a discontigious mapping. + */ + rmd.contiguous = !err_ptr; + rmd.no_translate = no_translate; + + while (nr) { + int index = 0; + int done = 0; + int batch = min(REMAP_BATCH_SIZE, nr); + int batch_left = batch; + range = (unsigned long)batch << PAGE_SHIFT; + + rmd.mmu_update = mmu_update; + err = apply_to_page_range(vma->vm_mm, addr, range, + remap_area_pfn_pte_fn, &rmd); + if (err) + goto out; + + /* We record the error for each page that gives an error, but + * continue mapping until the whole set is done */ + do { + int i; + + err = HYPERVISOR_mmu_update(&mmu_update[index], + batch_left, &done, domid); + + /* + * @err_ptr may be the same buffer as @gfn, so + * only clear it after each chunk of @gfn is + * used. + */ + if (err_ptr) { + for (i = index; i < index + done; i++) + err_ptr[i] = 0; + } + if (err < 0) { + if (!err_ptr) + goto out; + err_ptr[i] = err; + done++; /* Skip failed frame. */ + } else + mapped += done; + batch_left -= done; + index += done; + } while (batch_left); + + nr -= batch; + addr += range; + if (err_ptr) + err_ptr += batch; + cond_resched(); + } +out: + + xen_flush_tlb_all(); + + return err < 0 ? err : mapped; +} + +int xen_remap_domain_gfn_range(struct vm_area_struct *vma, + unsigned long addr, + xen_pfn_t gfn, int nr, + pgprot_t prot, unsigned domid, + struct page **pages) +{ + if (xen_feature(XENFEAT_auto_translated_physmap)) + return -EOPNOTSUPP; + + return do_remap_pfn(vma, addr, &gfn, nr, NULL, prot, domid, false, + pages); +} +EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_range); + +int xen_remap_domain_gfn_array(struct vm_area_struct *vma, + unsigned long addr, + xen_pfn_t *gfn, int nr, + int *err_ptr, pgprot_t prot, + unsigned domid, struct page **pages) +{ + if (xen_feature(XENFEAT_auto_translated_physmap)) + return xen_xlate_remap_gfn_array(vma, addr, gfn, nr, err_ptr, + prot, domid, pages); + + /* We BUG_ON because it's a programmer error to pass a NULL err_ptr, + * and the consequences later is quite hard to detect what the actual + * cause of "wrong memory was mapped in". + */ + BUG_ON(err_ptr == NULL); + return do_remap_pfn(vma, addr, gfn, nr, err_ptr, prot, domid, + false, pages); +} +EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_array); + +int xen_remap_domain_mfn_array(struct vm_area_struct *vma, + unsigned long addr, + xen_pfn_t *mfn, int nr, + int *err_ptr, pgprot_t prot, + unsigned int domid, struct page **pages) +{ + if (xen_feature(XENFEAT_auto_translated_physmap)) + return -EOPNOTSUPP; + + return do_remap_pfn(vma, addr, mfn, nr, err_ptr, prot, domid, + true, pages); +} +EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_array); + +/* Returns: 0 success */ +int xen_unmap_domain_gfn_range(struct vm_area_struct *vma, + int nr, struct page **pages) +{ + if (xen_feature(XENFEAT_auto_translated_physmap)) + return xen_xlate_unmap_gfn_range(vma, nr, pages); + + if (!pages) + return 0; + + return -EINVAL; +} +EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range); |