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Diffstat (limited to 'arch/x86/xen/mmu.c')
-rw-r--r--arch/x86/xen/mmu.c398
1 files changed, 240 insertions, 158 deletions
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 1d68be6e3ff1..f226038a39ca 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -535,40 +535,41 @@ static pgd_t *xen_get_user_pgd(pgd_t *pgd)
return user_ptr;
}
-static void __xen_set_pgd_hyper(pgd_t *ptr, pgd_t val)
+static void __xen_set_p4d_hyper(p4d_t *ptr, p4d_t val)
{
struct mmu_update u;
u.ptr = virt_to_machine(ptr).maddr;
- u.val = pgd_val_ma(val);
+ u.val = p4d_val_ma(val);
xen_extend_mmu_update(&u);
}
/*
- * Raw hypercall-based set_pgd, intended for in early boot before
+ * Raw hypercall-based set_p4d, intended for in early boot before
* there's a page structure. This implies:
* 1. The only existing pagetable is the kernel's
* 2. It is always pinned
* 3. It has no user pagetable attached to it
*/
-static void __init xen_set_pgd_hyper(pgd_t *ptr, pgd_t val)
+static void __init xen_set_p4d_hyper(p4d_t *ptr, p4d_t val)
{
preempt_disable();
xen_mc_batch();
- __xen_set_pgd_hyper(ptr, val);
+ __xen_set_p4d_hyper(ptr, val);
xen_mc_issue(PARAVIRT_LAZY_MMU);
preempt_enable();
}
-static void xen_set_pgd(pgd_t *ptr, pgd_t val)
+static void xen_set_p4d(p4d_t *ptr, p4d_t val)
{
- pgd_t *user_ptr = xen_get_user_pgd(ptr);
+ pgd_t *user_ptr = xen_get_user_pgd((pgd_t *)ptr);
+ pgd_t pgd_val;
- trace_xen_mmu_set_pgd(ptr, user_ptr, val);
+ trace_xen_mmu_set_p4d(ptr, (p4d_t *)user_ptr, val);
/* If page is not pinned, we can just update the entry
directly */
@@ -576,7 +577,8 @@ static void xen_set_pgd(pgd_t *ptr, pgd_t val)
*ptr = val;
if (user_ptr) {
WARN_ON(xen_page_pinned(user_ptr));
- *user_ptr = val;
+ pgd_val.pgd = p4d_val_ma(val);
+ *user_ptr = pgd_val;
}
return;
}
@@ -585,14 +587,72 @@ static void xen_set_pgd(pgd_t *ptr, pgd_t val)
user updates together. */
xen_mc_batch();
- __xen_set_pgd_hyper(ptr, val);
+ __xen_set_p4d_hyper(ptr, val);
if (user_ptr)
- __xen_set_pgd_hyper(user_ptr, val);
+ __xen_set_p4d_hyper((p4d_t *)user_ptr, val);
xen_mc_issue(PARAVIRT_LAZY_MMU);
}
#endif /* CONFIG_PGTABLE_LEVELS == 4 */
+static int xen_pmd_walk(struct mm_struct *mm, pmd_t *pmd,
+ int (*func)(struct mm_struct *mm, struct page *, enum pt_level),
+ bool last, unsigned long limit)
+{
+ int i, nr, flush = 0;
+
+ nr = last ? pmd_index(limit) + 1 : PTRS_PER_PMD;
+ for (i = 0; i < nr; i++) {
+ if (!pmd_none(pmd[i]))
+ flush |= (*func)(mm, pmd_page(pmd[i]), PT_PTE);
+ }
+ return flush;
+}
+
+static int xen_pud_walk(struct mm_struct *mm, pud_t *pud,
+ int (*func)(struct mm_struct *mm, struct page *, enum pt_level),
+ bool last, unsigned long limit)
+{
+ int i, nr, flush = 0;
+
+ nr = last ? pud_index(limit) + 1 : PTRS_PER_PUD;
+ for (i = 0; i < nr; i++) {
+ pmd_t *pmd;
+
+ if (pud_none(pud[i]))
+ continue;
+
+ pmd = pmd_offset(&pud[i], 0);
+ if (PTRS_PER_PMD > 1)
+ flush |= (*func)(mm, virt_to_page(pmd), PT_PMD);
+ flush |= xen_pmd_walk(mm, pmd, func,
+ last && i == nr - 1, limit);
+ }
+ return flush;
+}
+
+static int xen_p4d_walk(struct mm_struct *mm, p4d_t *p4d,
+ int (*func)(struct mm_struct *mm, struct page *, enum pt_level),
+ bool last, unsigned long limit)
+{
+ int i, nr, flush = 0;
+
+ nr = last ? p4d_index(limit) + 1 : PTRS_PER_P4D;
+ for (i = 0; i < nr; i++) {
+ pud_t *pud;
+
+ if (p4d_none(p4d[i]))
+ continue;
+
+ pud = pud_offset(&p4d[i], 0);
+ if (PTRS_PER_PUD > 1)
+ flush |= (*func)(mm, virt_to_page(pud), PT_PUD);
+ flush |= xen_pud_walk(mm, pud, func,
+ last && i == nr - 1, limit);
+ }
+ return flush;
+}
+
/*
* (Yet another) pagetable walker. This one is intended for pinning a
* pagetable. This means that it walks a pagetable and calls the
@@ -613,10 +673,8 @@ static int __xen_pgd_walk(struct mm_struct *mm, pgd_t *pgd,
enum pt_level),
unsigned long limit)
{
- int flush = 0;
+ int i, nr, flush = 0;
unsigned hole_low, hole_high;
- unsigned pgdidx_limit, pudidx_limit, pmdidx_limit;
- unsigned pgdidx, pudidx, pmdidx;
/* The limit is the last byte to be touched */
limit--;
@@ -633,65 +691,22 @@ static int __xen_pgd_walk(struct mm_struct *mm, pgd_t *pgd,
hole_low = pgd_index(USER_LIMIT);
hole_high = pgd_index(PAGE_OFFSET);
- pgdidx_limit = pgd_index(limit);
-#if PTRS_PER_PUD > 1
- pudidx_limit = pud_index(limit);
-#else
- pudidx_limit = 0;
-#endif
-#if PTRS_PER_PMD > 1
- pmdidx_limit = pmd_index(limit);
-#else
- pmdidx_limit = 0;
-#endif
-
- for (pgdidx = 0; pgdidx <= pgdidx_limit; pgdidx++) {
- pud_t *pud;
+ nr = pgd_index(limit) + 1;
+ for (i = 0; i < nr; i++) {
+ p4d_t *p4d;
- if (pgdidx >= hole_low && pgdidx < hole_high)
+ if (i >= hole_low && i < hole_high)
continue;
- if (!pgd_val(pgd[pgdidx]))
+ if (pgd_none(pgd[i]))
continue;
- pud = pud_offset(&pgd[pgdidx], 0);
-
- if (PTRS_PER_PUD > 1) /* not folded */
- flush |= (*func)(mm, virt_to_page(pud), PT_PUD);
-
- for (pudidx = 0; pudidx < PTRS_PER_PUD; pudidx++) {
- pmd_t *pmd;
-
- if (pgdidx == pgdidx_limit &&
- pudidx > pudidx_limit)
- goto out;
-
- if (pud_none(pud[pudidx]))
- continue;
-
- pmd = pmd_offset(&pud[pudidx], 0);
-
- if (PTRS_PER_PMD > 1) /* not folded */
- flush |= (*func)(mm, virt_to_page(pmd), PT_PMD);
-
- for (pmdidx = 0; pmdidx < PTRS_PER_PMD; pmdidx++) {
- struct page *pte;
-
- if (pgdidx == pgdidx_limit &&
- pudidx == pudidx_limit &&
- pmdidx > pmdidx_limit)
- goto out;
-
- if (pmd_none(pmd[pmdidx]))
- continue;
-
- pte = pmd_page(pmd[pmdidx]);
- flush |= (*func)(mm, pte, PT_PTE);
- }
- }
+ p4d = p4d_offset(&pgd[i], 0);
+ if (PTRS_PER_P4D > 1)
+ flush |= (*func)(mm, virt_to_page(p4d), PT_P4D);
+ flush |= xen_p4d_walk(mm, p4d, func, i == nr - 1, limit);
}
-out:
/* Do the top level last, so that the callbacks can use it as
a cue to do final things like tlb flushes. */
flush |= (*func)(mm, virt_to_page(pgd), PT_PGD);
@@ -1150,57 +1165,97 @@ static void __init xen_cleanmfnmap_free_pgtbl(void *pgtbl, bool unpin)
xen_free_ro_pages(pa, PAGE_SIZE);
}
+static void __init xen_cleanmfnmap_pmd(pmd_t *pmd, bool unpin)
+{
+ unsigned long pa;
+ pte_t *pte_tbl;
+ int i;
+
+ if (pmd_large(*pmd)) {
+ pa = pmd_val(*pmd) & PHYSICAL_PAGE_MASK;
+ xen_free_ro_pages(pa, PMD_SIZE);
+ return;
+ }
+
+ pte_tbl = pte_offset_kernel(pmd, 0);
+ for (i = 0; i < PTRS_PER_PTE; i++) {
+ if (pte_none(pte_tbl[i]))
+ continue;
+ pa = pte_pfn(pte_tbl[i]) << PAGE_SHIFT;
+ xen_free_ro_pages(pa, PAGE_SIZE);
+ }
+ set_pmd(pmd, __pmd(0));
+ xen_cleanmfnmap_free_pgtbl(pte_tbl, unpin);
+}
+
+static void __init xen_cleanmfnmap_pud(pud_t *pud, bool unpin)
+{
+ unsigned long pa;
+ pmd_t *pmd_tbl;
+ int i;
+
+ if (pud_large(*pud)) {
+ pa = pud_val(*pud) & PHYSICAL_PAGE_MASK;
+ xen_free_ro_pages(pa, PUD_SIZE);
+ return;
+ }
+
+ pmd_tbl = pmd_offset(pud, 0);
+ for (i = 0; i < PTRS_PER_PMD; i++) {
+ if (pmd_none(pmd_tbl[i]))
+ continue;
+ xen_cleanmfnmap_pmd(pmd_tbl + i, unpin);
+ }
+ set_pud(pud, __pud(0));
+ xen_cleanmfnmap_free_pgtbl(pmd_tbl, unpin);
+}
+
+static void __init xen_cleanmfnmap_p4d(p4d_t *p4d, bool unpin)
+{
+ unsigned long pa;
+ pud_t *pud_tbl;
+ int i;
+
+ if (p4d_large(*p4d)) {
+ pa = p4d_val(*p4d) & PHYSICAL_PAGE_MASK;
+ xen_free_ro_pages(pa, P4D_SIZE);
+ return;
+ }
+
+ pud_tbl = pud_offset(p4d, 0);
+ for (i = 0; i < PTRS_PER_PUD; i++) {
+ if (pud_none(pud_tbl[i]))
+ continue;
+ xen_cleanmfnmap_pud(pud_tbl + i, unpin);
+ }
+ set_p4d(p4d, __p4d(0));
+ xen_cleanmfnmap_free_pgtbl(pud_tbl, unpin);
+}
+
/*
* Since it is well isolated we can (and since it is perhaps large we should)
* also free the page tables mapping the initial P->M table.
*/
static void __init xen_cleanmfnmap(unsigned long vaddr)
{
- unsigned long va = vaddr & PMD_MASK;
- unsigned long pa;
- pgd_t *pgd = pgd_offset_k(va);
- pud_t *pud_page = pud_offset(pgd, 0);
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte;
+ pgd_t *pgd;
+ p4d_t *p4d;
unsigned int i;
bool unpin;
unpin = (vaddr == 2 * PGDIR_SIZE);
- set_pgd(pgd, __pgd(0));
- do {
- pud = pud_page + pud_index(va);
- if (pud_none(*pud)) {
- va += PUD_SIZE;
- } else if (pud_large(*pud)) {
- pa = pud_val(*pud) & PHYSICAL_PAGE_MASK;
- xen_free_ro_pages(pa, PUD_SIZE);
- va += PUD_SIZE;
- } else {
- pmd = pmd_offset(pud, va);
- if (pmd_large(*pmd)) {
- pa = pmd_val(*pmd) & PHYSICAL_PAGE_MASK;
- xen_free_ro_pages(pa, PMD_SIZE);
- } else if (!pmd_none(*pmd)) {
- pte = pte_offset_kernel(pmd, va);
- set_pmd(pmd, __pmd(0));
- for (i = 0; i < PTRS_PER_PTE; ++i) {
- if (pte_none(pte[i]))
- break;
- pa = pte_pfn(pte[i]) << PAGE_SHIFT;
- xen_free_ro_pages(pa, PAGE_SIZE);
- }
- xen_cleanmfnmap_free_pgtbl(pte, unpin);
- }
- va += PMD_SIZE;
- if (pmd_index(va))
- continue;
- set_pud(pud, __pud(0));
- xen_cleanmfnmap_free_pgtbl(pmd, unpin);
- }
-
- } while (pud_index(va) || pmd_index(va));
- xen_cleanmfnmap_free_pgtbl(pud_page, unpin);
+ vaddr &= PMD_MASK;
+ pgd = pgd_offset_k(vaddr);
+ p4d = p4d_offset(pgd, 0);
+ for (i = 0; i < PTRS_PER_P4D; i++) {
+ if (p4d_none(p4d[i]))
+ continue;
+ xen_cleanmfnmap_p4d(p4d + i, unpin);
+ }
+ if (IS_ENABLED(CONFIG_X86_5LEVEL)) {
+ set_pgd(pgd, __pgd(0));
+ xen_cleanmfnmap_free_pgtbl(p4d, unpin);
+ }
}
static void __init xen_pagetable_p2m_free(void)
@@ -1538,7 +1593,6 @@ static int xen_pgd_alloc(struct mm_struct *mm)
BUG_ON(PagePinned(virt_to_page(xen_get_user_pgd(pgd))));
}
#endif
-
return ret;
}
@@ -1730,7 +1784,7 @@ static void xen_release_pmd(unsigned long pfn)
xen_release_ptpage(pfn, PT_PMD);
}
-#if CONFIG_PGTABLE_LEVELS == 4
+#if CONFIG_PGTABLE_LEVELS >= 4
static void xen_alloc_pud(struct mm_struct *mm, unsigned long pfn)
{
xen_alloc_ptpage(mm, pfn, PT_PUD);
@@ -2071,21 +2125,27 @@ static phys_addr_t __init xen_early_virt_to_phys(unsigned long vaddr)
*/
void __init xen_relocate_p2m(void)
{
- phys_addr_t size, new_area, pt_phys, pmd_phys, pud_phys;
+ phys_addr_t size, new_area, pt_phys, pmd_phys, pud_phys, p4d_phys;
unsigned long p2m_pfn, p2m_pfn_end, n_frames, pfn, pfn_end;
- int n_pte, n_pt, n_pmd, n_pud, idx_pte, idx_pt, idx_pmd, idx_pud;
+ int n_pte, n_pt, n_pmd, n_pud, n_p4d, idx_pte, idx_pt, idx_pmd, idx_pud, idx_p4d;
pte_t *pt;
pmd_t *pmd;
pud_t *pud;
+ p4d_t *p4d = NULL;
pgd_t *pgd;
unsigned long *new_p2m;
+ int save_pud;
size = PAGE_ALIGN(xen_start_info->nr_pages * sizeof(unsigned long));
n_pte = roundup(size, PAGE_SIZE) >> PAGE_SHIFT;
n_pt = roundup(size, PMD_SIZE) >> PMD_SHIFT;
n_pmd = roundup(size, PUD_SIZE) >> PUD_SHIFT;
- n_pud = roundup(size, PGDIR_SIZE) >> PGDIR_SHIFT;
- n_frames = n_pte + n_pt + n_pmd + n_pud;
+ n_pud = roundup(size, P4D_SIZE) >> P4D_SHIFT;
+ if (PTRS_PER_P4D > 1)
+ n_p4d = roundup(size, PGDIR_SIZE) >> PGDIR_SHIFT;
+ else
+ n_p4d = 0;
+ n_frames = n_pte + n_pt + n_pmd + n_pud + n_p4d;
new_area = xen_find_free_area(PFN_PHYS(n_frames));
if (!new_area) {
@@ -2101,55 +2161,76 @@ void __init xen_relocate_p2m(void)
* To avoid any possible virtual address collision, just use
* 2 * PUD_SIZE for the new area.
*/
- pud_phys = new_area;
+ p4d_phys = new_area;
+ pud_phys = p4d_phys + PFN_PHYS(n_p4d);
pmd_phys = pud_phys + PFN_PHYS(n_pud);
pt_phys = pmd_phys + PFN_PHYS(n_pmd);
p2m_pfn = PFN_DOWN(pt_phys) + n_pt;
pgd = __va(read_cr3());
new_p2m = (unsigned long *)(2 * PGDIR_SIZE);
- for (idx_pud = 0; idx_pud < n_pud; idx_pud++) {
- pud = early_memremap(pud_phys, PAGE_SIZE);
- clear_page(pud);
- for (idx_pmd = 0; idx_pmd < min(n_pmd, PTRS_PER_PUD);
- idx_pmd++) {
- pmd = early_memremap(pmd_phys, PAGE_SIZE);
- clear_page(pmd);
- for (idx_pt = 0; idx_pt < min(n_pt, PTRS_PER_PMD);
- idx_pt++) {
- pt = early_memremap(pt_phys, PAGE_SIZE);
- clear_page(pt);
- for (idx_pte = 0;
- idx_pte < min(n_pte, PTRS_PER_PTE);
- idx_pte++) {
- set_pte(pt + idx_pte,
- pfn_pte(p2m_pfn, PAGE_KERNEL));
- p2m_pfn++;
+ idx_p4d = 0;
+ save_pud = n_pud;
+ do {
+ if (n_p4d > 0) {
+ p4d = early_memremap(p4d_phys, PAGE_SIZE);
+ clear_page(p4d);
+ n_pud = min(save_pud, PTRS_PER_P4D);
+ }
+ for (idx_pud = 0; idx_pud < n_pud; idx_pud++) {
+ pud = early_memremap(pud_phys, PAGE_SIZE);
+ clear_page(pud);
+ for (idx_pmd = 0; idx_pmd < min(n_pmd, PTRS_PER_PUD);
+ idx_pmd++) {
+ pmd = early_memremap(pmd_phys, PAGE_SIZE);
+ clear_page(pmd);
+ for (idx_pt = 0; idx_pt < min(n_pt, PTRS_PER_PMD);
+ idx_pt++) {
+ pt = early_memremap(pt_phys, PAGE_SIZE);
+ clear_page(pt);
+ for (idx_pte = 0;
+ idx_pte < min(n_pte, PTRS_PER_PTE);
+ idx_pte++) {
+ set_pte(pt + idx_pte,
+ pfn_pte(p2m_pfn, PAGE_KERNEL));
+ p2m_pfn++;
+ }
+ n_pte -= PTRS_PER_PTE;
+ early_memunmap(pt, PAGE_SIZE);
+ make_lowmem_page_readonly(__va(pt_phys));
+ pin_pagetable_pfn(MMUEXT_PIN_L1_TABLE,
+ PFN_DOWN(pt_phys));
+ set_pmd(pmd + idx_pt,
+ __pmd(_PAGE_TABLE | pt_phys));
+ pt_phys += PAGE_SIZE;
}
- n_pte -= PTRS_PER_PTE;
- early_memunmap(pt, PAGE_SIZE);
- make_lowmem_page_readonly(__va(pt_phys));
- pin_pagetable_pfn(MMUEXT_PIN_L1_TABLE,
- PFN_DOWN(pt_phys));
- set_pmd(pmd + idx_pt,
- __pmd(_PAGE_TABLE | pt_phys));
- pt_phys += PAGE_SIZE;
+ n_pt -= PTRS_PER_PMD;
+ early_memunmap(pmd, PAGE_SIZE);
+ make_lowmem_page_readonly(__va(pmd_phys));
+ pin_pagetable_pfn(MMUEXT_PIN_L2_TABLE,
+ PFN_DOWN(pmd_phys));
+ set_pud(pud + idx_pmd, __pud(_PAGE_TABLE | pmd_phys));
+ pmd_phys += PAGE_SIZE;
}
- n_pt -= PTRS_PER_PMD;
- early_memunmap(pmd, PAGE_SIZE);
- make_lowmem_page_readonly(__va(pmd_phys));
- pin_pagetable_pfn(MMUEXT_PIN_L2_TABLE,
- PFN_DOWN(pmd_phys));
- set_pud(pud + idx_pmd, __pud(_PAGE_TABLE | pmd_phys));
- pmd_phys += PAGE_SIZE;
+ n_pmd -= PTRS_PER_PUD;
+ early_memunmap(pud, PAGE_SIZE);
+ make_lowmem_page_readonly(__va(pud_phys));
+ pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE, PFN_DOWN(pud_phys));
+ if (n_p4d > 0)
+ set_p4d(p4d + idx_pud, __p4d(_PAGE_TABLE | pud_phys));
+ else
+ set_pgd(pgd + 2 + idx_pud, __pgd(_PAGE_TABLE | pud_phys));
+ pud_phys += PAGE_SIZE;
}
- n_pmd -= PTRS_PER_PUD;
- early_memunmap(pud, PAGE_SIZE);
- make_lowmem_page_readonly(__va(pud_phys));
- pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE, PFN_DOWN(pud_phys));
- set_pgd(pgd + 2 + idx_pud, __pgd(_PAGE_TABLE | pud_phys));
- pud_phys += PAGE_SIZE;
- }
+ if (n_p4d > 0) {
+ save_pud -= PTRS_PER_P4D;
+ early_memunmap(p4d, PAGE_SIZE);
+ make_lowmem_page_readonly(__va(p4d_phys));
+ pin_pagetable_pfn(MMUEXT_PIN_L4_TABLE, PFN_DOWN(p4d_phys));
+ set_pgd(pgd + 2 + idx_p4d, __pgd(_PAGE_TABLE | p4d_phys));
+ p4d_phys += PAGE_SIZE;
+ }
+ } while (++idx_p4d < n_p4d);
/* Now copy the old p2m info to the new area. */
memcpy(new_p2m, xen_p2m_addr, size);
@@ -2326,6 +2407,7 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot)
#endif
case FIX_TEXT_POKE0:
case FIX_TEXT_POKE1:
+ case FIX_GDT_REMAP_BEGIN ... FIX_GDT_REMAP_END:
/* All local page mappings */
pte = pfn_pte(phys, prot);
break;
@@ -2378,8 +2460,8 @@ static void __init xen_post_allocator_init(void)
pv_mmu_ops.set_pte = xen_set_pte;
pv_mmu_ops.set_pmd = xen_set_pmd;
pv_mmu_ops.set_pud = xen_set_pud;
-#if CONFIG_PGTABLE_LEVELS == 4
- pv_mmu_ops.set_pgd = xen_set_pgd;
+#if CONFIG_PGTABLE_LEVELS >= 4
+ pv_mmu_ops.set_p4d = xen_set_p4d;
#endif
/* This will work as long as patching hasn't happened yet
@@ -2388,7 +2470,7 @@ static void __init xen_post_allocator_init(void)
pv_mmu_ops.alloc_pmd = xen_alloc_pmd;
pv_mmu_ops.release_pte = xen_release_pte;
pv_mmu_ops.release_pmd = xen_release_pmd;
-#if CONFIG_PGTABLE_LEVELS == 4
+#if CONFIG_PGTABLE_LEVELS >= 4
pv_mmu_ops.alloc_pud = xen_alloc_pud;
pv_mmu_ops.release_pud = xen_release_pud;
#endif
@@ -2454,10 +2536,10 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = {
.make_pmd = PV_CALLEE_SAVE(xen_make_pmd),
.pmd_val = PV_CALLEE_SAVE(xen_pmd_val),
-#if CONFIG_PGTABLE_LEVELS == 4
+#if CONFIG_PGTABLE_LEVELS >= 4
.pud_val = PV_CALLEE_SAVE(xen_pud_val),
.make_pud = PV_CALLEE_SAVE(xen_make_pud),
- .set_pgd = xen_set_pgd_hyper,
+ .set_p4d = xen_set_p4d_hyper,
.alloc_pud = xen_alloc_pmd_init,
.release_pud = xen_release_pmd_init,