On Thu, 4 Oct 2012 09:27:59 +0100
Ian Campbell <Ian.Campbell@citrix.com> wrote:
> On Wed, 2012-10-03 at 23:29 +0100, Mukesh Rathor wrote:
> > On Wed, 3 Oct 2012 16:42:43 +0100
> > Ian Campbell <Ian.Campbell@citrix.com> wrote:
> >
> While implementing the ARM version of this interface it occurred to me
> that the num_pgs and next_todo fields here are not really needed
> across the arch interface e.g. you already get pi_num_pgs from the nr
> argument to xen_remap_domain_mfn_range and pi_next_todo is really
> state which fits in struct pvh_remap_data. That would mean that
> remap_foo could take a struct page * directly and I think you would
> save an allocation.
Ok, take a look at the attached and inlined diffs. I redid it, passing
struct page to the api, and getting rid of the pi_* struct completely.
thanks
Mukesh
diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c
index ef63895..6cbf59a 100644
--- a/drivers/xen/privcmd.c
+++ b/drivers/xen/privcmd.c
@@ -33,6 +33,7 @@
#include <xen/features.h>
#include <xen/page.h>
#include <xen/xen-ops.h>
+#include <xen/balloon.h>
#include "privcmd.h"
@@ -178,7 +179,7 @@ static int mmap_mfn_range(void *data, void *state)
msg->va & PAGE_MASK,
msg->mfn, msg->npages,
vma->vm_page_prot,
- st->domain);
+ st->domain, NULL);
if (rc < 0)
return rc;
@@ -199,6 +200,10 @@ static long privcmd_ioctl_mmap(void __user *udata)
if (!xen_initial_domain())
return -EPERM;
+ /* We only support privcmd_ioctl_mmap_batch for auto translated. */
+ if (xen_feature(XENFEAT_auto_translated_physmap))
+ return -ENOSYS;
+
if (copy_from_user(&mmapcmd, udata, sizeof(mmapcmd)))
return -EFAULT;
@@ -246,6 +251,7 @@ struct mmap_batch_state {
domid_t domain;
unsigned long va;
struct vm_area_struct *vma;
+ int index;
/* A tristate:
* 0 for no errors
* 1 if at least one error has happened (and no
@@ -260,14 +266,20 @@ struct mmap_batch_state {
xen_pfn_t __user *user_mfn;
};
+/* PVH dom0 fyi: if domU being created is PV, then mfn is mfn(addr on bus). If
+ * it's PVH then mfn is pfn (input to HAP). */
static int mmap_batch_fn(void *data, void *state)
{
xen_pfn_t *mfnp = data;
struct mmap_batch_state *st = state;
+ struct vm_area_struct *vma = st->vma;
+ struct page **pages = vma ? vma->vm_private_data : NULL;
+ struct page *cur_page = pages[st->index++];
int ret;
ret = xen_remap_domain_mfn_range(st->vma, st->va & PAGE_MASK, *mfnp, 1,
- st->vma->vm_page_prot, st->domain);
+ st->vma->vm_page_prot, st->domain,
+ &cur_page);
/* Store error code for second pass. */
*(st->err++) = ret;
@@ -303,6 +315,32 @@ static int mmap_return_errors_v1(void *data, void *state)
return __put_user(*mfnp, st->user_mfn++);
}
+/* Allocate pfns that are then mapped with gmfns from foreign domid. Update
+ * the vma with the page info to use later.
+ * Returns: 0 if success, otherwise -errno
+ */
+static int pvh_privcmd_resv_pfns(struct vm_area_struct *vma, int numpgs)
+{
+ int rc;
+ struct page **pages;
+
+ pages = kcalloc(numpgs, sizeof(pages[0]), GFP_KERNEL);
+ if (pages == NULL)
+ return -ENOMEM;
+
+ rc = alloc_xenballooned_pages(numpgs, pages, 0);
+ if (rc != 0) {
+ pr_warn("%s Could not alloc %d pfns rc:%d\n", __func__,
+ numpgs, rc);
+ kfree(pages);
+ return -ENOMEM;
+ }
+ BUG_ON(vma->vm_private_data);
+ vma->vm_private_data = pages;
+
+ return 0;
+}
+
static struct vm_operations_struct privcmd_vm_ops;
static long privcmd_ioctl_mmap_batch(void __user *udata, int version)
@@ -370,10 +408,17 @@ static long privcmd_ioctl_mmap_batch(void __user *udata, int version)
up_write(&mm->mmap_sem);
goto out;
}
+ if (xen_feature(XENFEAT_auto_translated_physmap)) {
+ if ((ret = pvh_privcmd_resv_pfns(vma, m.num)) < 0) {
+ up_write(&mm->mmap_sem);
+ goto out;
+ }
+ }
state.domain = m.dom;
state.vma = vma;
state.va = m.addr;
+ state.index = 0;
state.global_error = 0;
state.err = err_array;
@@ -438,6 +483,20 @@ static long privcmd_ioctl(struct file *file,
return ret;
}
+static void privcmd_close(struct vm_area_struct *vma)
+{
+ struct page **pages = vma ? vma->vm_private_data : NULL;
+ int numpgs = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+
+ if (!pages || !numpgs || !xen_feature(XENFEAT_auto_translated_physmap))
+ return;
+
+ xen_unmap_domain_mfn_range(vma);
+ while (numpgs--)
+ free_xenballooned_pages(1, &pages[numpgs]);
+ kfree(pages);
+}
+
static int privcmd_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
{
printk(KERN_DEBUG "privcmd_fault: vma=%p %lx-%lx, pgoff=%lx, uv=%p\n",
@@ -448,6 +507,7 @@ static int privcmd_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
}
static struct vm_operations_struct privcmd_vm_ops = {
+ .close = privcmd_close,
.fault = privcmd_fault
};
@@ -464,6 +524,10 @@ static int privcmd_mmap(struct file *file, struct vm_area_struct *vma)
static int privcmd_enforce_singleshot_mapping(struct vm_area_struct *vma)
{
+ if (xen_feature(XENFEAT_auto_translated_physmap)) {
+ int sz = sizeof(vma->vm_private_data);
+ return (!__cmpxchg(&vma->vm_private_data, NULL, NULL, sz));
+ }
return (xchg(&vma->vm_private_data, (void *)1) == NULL);
}
===============================================================================================
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 5a16824..d5e53ad 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -73,6 +73,7 @@
#include <xen/interface/version.h>
#include <xen/interface/memory.h>
#include <xen/hvc-console.h>
+#include <xen/balloon.h>
#include "multicalls.h"
#include "mmu.h"
@@ -331,6 +332,20 @@ static void xen_set_pte(pte_t *ptep, pte_t pteval)
__xen_set_pte(ptep, pteval);
}
+void xen_set_clr_mmio_pvh_pte(unsigned long pfn, unsigned long mfn,
+ int nr_mfns, int add_mapping)
+{
+ struct physdev_map_iomem iomem;
+
+ iomem.first_gfn = pfn;
+ iomem.first_mfn = mfn;
+ iomem.nr_mfns = nr_mfns;
+ iomem.add_mapping = add_mapping;
+
+ if (HYPERVISOR_physdev_op(PHYSDEVOP_pvh_map_iomem, &iomem))
+ BUG();
+}
+
static void xen_set_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pteval)
{
@@ -1220,6 +1235,8 @@ static void __init xen_pagetable_init(void)
#endif
paging_init();
xen_setup_shared_info();
+ if (xen_feature(XENFEAT_auto_translated_physmap))
+ return;
#ifdef CONFIG_X86_64
if (!xen_feature(XENFEAT_auto_translated_physmap)) {
unsigned long new_mfn_list;
@@ -1527,6 +1544,10 @@ static void __init xen_set_pte_init(pte_t *ptep, pte_t pte)
static void pin_pagetable_pfn(unsigned cmd, unsigned long pfn)
{
struct mmuext_op op;
+
+ if (xen_feature(XENFEAT_writable_page_tables))
+ return;
+
op.cmd = cmd;
op.arg1.mfn = pfn_to_mfn(pfn);
if (HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF))
@@ -1724,6 +1745,10 @@ static void set_page_prot(void *addr, pgprot_t prot)
unsigned long pfn = __pa(addr) >> PAGE_SHIFT;
pte_t pte = pfn_pte(pfn, prot);
+ /* recall for PVH, page tables are native. */
+ if (xen_feature(XENFEAT_auto_translated_physmap))
+ return;
+
if (HYPERVISOR_update_va_mapping((unsigned long)addr, pte, 0))
BUG();
}
@@ -1801,6 +1826,9 @@ static void convert_pfn_mfn(void *v)
pte_t *pte = v;
int i;
+ if (xen_feature(XENFEAT_auto_translated_physmap))
+ return;
+
/* All levels are converted the same way, so just treat them
as ptes. */
for (i = 0; i < PTRS_PER_PTE; i++)
@@ -1820,6 +1848,7 @@ static void __init check_pt_base(unsigned long *pt_base, unsigned long *pt_end,
(*pt_end)--;
}
}
+
/*
* Set up the initial kernel pagetable.
*
@@ -1830,6 +1859,7 @@ static void __init check_pt_base(unsigned long *pt_base, unsigned long *pt_end,
* but that's enough to get __va working. We need to fill in the rest
* of the physical mapping once some sort of allocator has been set
* up.
+ * NOTE: for PVH, the page tables are native.
*/
void __init xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn)
{
@@ -1907,10 +1937,13 @@ void __init xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn)
* structure to attach it to, so make sure we just set kernel
* pgd.
*/
- xen_mc_batch();
- __xen_write_cr3(true, __pa(init_level4_pgt));
- xen_mc_issue(PARAVIRT_LAZY_CPU);
-
+ if (xen_feature(XENFEAT_writable_page_tables)) {
+ native_write_cr3(__pa(init_level4_pgt));
+ } else {
+ xen_mc_batch();
+ __xen_write_cr3(true, __pa(init_level4_pgt));
+ xen_mc_issue(PARAVIRT_LAZY_CPU);
+ }
/* We can't that easily rip out L3 and L2, as the Xen pagetables are
* set out this way: [L4], [L1], [L2], [L3], [L1], [L1] ... for
* the initial domain. For guests using the toolstack, they are in:
@@ -2177,8 +2210,19 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = {
void __init xen_init_mmu_ops(void)
{
- x86_init.mapping.pagetable_reserve = xen_mapping_pagetable_reserve;
x86_init.paging.pagetable_init = xen_pagetable_init;
+
+ if (xen_feature(XENFEAT_auto_translated_physmap)) {
+ pv_mmu_ops.flush_tlb_others = xen_flush_tlb_others;
+
+ /* set_pte* for PCI devices to map iomem. */
+ if (xen_initial_domain()) {
+ pv_mmu_ops.set_pte = native_set_pte;
+ pv_mmu_ops.set_pte_at = native_set_pte_at;
+ }
+ return;
+ }
+ x86_init.mapping.pagetable_reserve = xen_mapping_pagetable_reserve;
pv_mmu_ops = xen_mmu_ops;
memset(dummy_mapping, 0xff, PAGE_SIZE);
@@ -2414,6 +2458,94 @@ void __init xen_hvm_init_mmu_ops(void)
}
#endif
+/* Map foreign gmfn, fgmfn, to local pfn, lpfn. This for the user space
+ * creating new guest on PVH dom0 and needs to map domU pages.
+ */
+static int pvh_add_to_xen_p2m(unsigned long lpfn, unsigned long fgmfn,
+ unsigned int domid)
+{
+ int rc;
+ struct xen_add_to_physmap xatp = { .u.foreign_domid = domid };
+
+ xatp.gpfn = lpfn;
+ xatp.idx = fgmfn;
+ xatp.domid = DOMID_SELF;
+ xatp.space = XENMAPSPACE_gmfn_foreign;
+ rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp);
+ if (rc)
+ pr_warn("d0: Failed to map pfn to mfn rc:%d pfn:%lx mfn:%lx\n",
+ rc, lpfn, fgmfn);
+ return rc;
+}
+
+int pvh_rem_xen_p2m(unsigned long spfn, int count)
+{
+ struct xen_remove_from_physmap xrp;
+ int i, rc;
+
+ for (i=0; i < count; i++) {
+ xrp.domid = DOMID_SELF;
+ xrp.gpfn = spfn+i;
+ rc = HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp);
+ if (rc) {
+ pr_warn("Failed to unmap pfn:%lx rc:%d done:%d\n",
+ spfn+i, rc, i);
+ return 1;
+ }
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pvh_rem_xen_p2m);
+
+struct pvh_remap_data {
+ unsigned long fgmfn; /* foreign domain's gmfn */
+ pgprot_t prot;
+ domid_t domid;
+ int index;
+ struct page **pages;
+};
+
+static int pvh_map_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr,
+ void *data)
+{
+ int rc;
+ struct pvh_remap_data *remap = data;
+ unsigned long pfn = page_to_pfn(remap->pages[remap->index++]);
+ pte_t pteval = pte_mkspecial(pfn_pte(pfn, remap->prot));
+
+ if ((rc=pvh_add_to_xen_p2m(pfn, remap->fgmfn, remap->domid)))
+ return rc;
+ native_set_pte(ptep, pteval);
+
+ return 0;
+}
+
+/* The only caller at moment passes one gmfn at a time.
+ * PVH TBD/FIXME: expand this in future to honor batch requests.
+ */
+static int pvh_remap_gmfn_range(struct vm_area_struct *vma,
+ unsigned long addr, unsigned long mfn, int nr,
+ pgprot_t prot, unsigned domid,
+ struct page **pages)
+{
+ int err;
+ struct pvh_remap_data pvhdata;
+
+ if (nr > 1)
+ return -EINVAL;
+
+ pvhdata.fgmfn = mfn;
+ pvhdata.prot = prot;
+ pvhdata.domid = domid;
+ pvhdata.index = 0;
+ pvhdata.pages = pages;
+ err = apply_to_page_range(vma->vm_mm, addr, nr << PAGE_SHIFT,
+ pvh_map_pte_fn, &pvhdata);
+ flush_tlb_all();
+ /* flush_tlb_page(vma, addr); */
+ return err;
+}
+
#define REMAP_BATCH_SIZE 16
struct remap_data {
@@ -2438,7 +2570,9 @@ static int remap_area_mfn_pte_fn(pte_t *ptep, pgtable_t token,
int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
unsigned long addr,
unsigned long mfn, int nr,
- pgprot_t prot, unsigned domid)
+ pgprot_t prot, unsigned domid,
+ struct page **pages)
+
{
struct remap_data rmd;
struct mmu_update mmu_update[REMAP_BATCH_SIZE];
@@ -2446,14 +2580,17 @@ int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
unsigned long range;
int err = 0;
- if (xen_feature(XENFEAT_auto_translated_physmap))
- return -EINVAL;
-
prot = __pgprot(pgprot_val(prot) | _PAGE_IOMAP);
BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_RESERVED | VM_IO)) ==
(VM_PFNMAP | VM_RESERVED | VM_IO)));
+ if (xen_feature(XENFEAT_auto_translated_physmap)) {
+ /* We need to update the local page tables and the xen HAP */
+ return pvh_remap_gmfn_range(vma, addr, mfn, nr, prot, domid,
+ pages);
+ }
+
rmd.mfn = mfn;
rmd.prot = prot;
@@ -2483,3 +2620,25 @@ out:
return err;
}
EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range);
+
+/* Returns: 0 success */
+int xen_unmap_domain_mfn_range(struct vm_area_struct *vma)
+{
+ int numpgs = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+ struct page **pages = vma ? vma->vm_private_data : NULL;
+
+ if (!pages || !xen_feature(XENFEAT_auto_translated_physmap))
+ return 0;
+
+ while (numpgs--) {
+
+ /* the mmu has already cleaned up the process mmu resources at
+ * this point (lookup_address will return NULL). */
+ unsigned long pfn = page_to_pfn(pages[numpgs]);
+
+ pvh_rem_xen_p2m(pfn, 1);
+ }
+ flush_tlb_all();
+ return 0;
+}
+EXPORT_SYMBOL_GPL(xen_unmap_domain_mfn_range);
