Implement vmap_pfn, so that we can remap discontiguous ranges of
persistent memory into a contiguous address range.
---
include/linux/vmalloc.h | 2 +
mm/vmalloc.c | 88 +++++++++++++++++++++++++++++++++++++-----------
2 files changed, 71 insertions(+), 19 deletions(-)
Index: linux-2.6/include/linux/vmalloc.h
===================================================================
--- linux-2.6.orig/include/linux/vmalloc.h
+++ linux-2.6/include/linux/vmalloc.h
@@ -97,6 +97,8 @@ extern void vfree_atomic(const void *add
extern void *vmap(struct page **pages, unsigned int count,
unsigned long flags, pgprot_t prot);
+extern void *vmap_pfn(pfn_t *pfns, unsigned int count,
+ unsigned long flags, pgprot_t prot);
extern void vunmap(const void *addr);
extern int remap_vmalloc_range_partial(struct vm_area_struct *vma,
Index: linux-2.6/mm/vmalloc.c
===================================================================
--- linux-2.6.orig/mm/vmalloc.c
+++ linux-2.6/mm/vmalloc.c
@@ -31,6 +31,7 @@
#include <linux/compiler.h>
#include <linux/llist.h>
#include <linux/bitops.h>
+#include <linux/pfn_t.h>
#include <linux/uaccess.h>
#include <asm/tlbflush.h>
@@ -134,7 +135,7 @@ static void vunmap_page_range(unsigned l
}
static int vmap_pte_range(pmd_t *pmd, unsigned long addr,
- unsigned long end, pgprot_t prot, struct page **pages, int *nr)
+ unsigned long end, pgprot_t prot, struct page **pages, pfn_t
*pfns, int *nr)
{
pte_t *pte;
@@ -147,20 +148,25 @@ static int vmap_pte_range(pmd_t *pmd, un
if (!pte)
return -ENOMEM;
do {
- struct page *page = pages[*nr];
-
+ unsigned long pf;
+ if (pages) {
+ struct page *page = pages[*nr];
+ if (WARN_ON(!page))
+ return -ENOMEM;
+ pf = page_to_pfn(page);
+ } else {
+ pf = pfn_t_to_pfn(pfns[*nr]);
+ }
if (WARN_ON(!pte_none(*pte)))
return -EBUSY;
- if (WARN_ON(!page))
- return -ENOMEM;
- set_pte_at(&init_mm, addr, pte, mk_pte(page, prot));
+ set_pte_at(&init_mm, addr, pte, pfn_pte(pf, prot));
(*nr)++;
} while (pte++, addr += PAGE_SIZE, addr != end);
return 0;
}
static int vmap_pmd_range(pud_t *pud, unsigned long addr,
- unsigned long end, pgprot_t prot, struct page **pages, int *nr)
+ unsigned long end, pgprot_t prot, struct page **pages, pfn_t
*pfns, int *nr)
{
pmd_t *pmd;
unsigned long next;
@@ -170,14 +176,14 @@ static int vmap_pmd_range(pud_t *pud, un
return -ENOMEM;
do {
next = pmd_addr_end(addr, end);
- if (vmap_pte_range(pmd, addr, next, prot, pages, nr))
+ if (vmap_pte_range(pmd, addr, next, prot, pages, pfns, nr))
return -ENOMEM;
} while (pmd++, addr = next, addr != end);
return 0;
}
static int vmap_pud_range(p4d_t *p4d, unsigned long addr,
- unsigned long end, pgprot_t prot, struct page **pages, int *nr)
+ unsigned long end, pgprot_t prot, struct page **pages, pfn_t
*pfns, int *nr)
{
pud_t *pud;
unsigned long next;
@@ -187,14 +193,14 @@ static int vmap_pud_range(p4d_t *p4d, un
return -ENOMEM;
do {
next = pud_addr_end(addr, end);
- if (vmap_pmd_range(pud, addr, next, prot, pages, nr))
+ if (vmap_pmd_range(pud, addr, next, prot, pages, pfns, nr))
return -ENOMEM;
} while (pud++, addr = next, addr != end);
return 0;
}
static int vmap_p4d_range(pgd_t *pgd, unsigned long addr,
- unsigned long end, pgprot_t prot, struct page **pages, int *nr)
+ unsigned long end, pgprot_t prot, struct page **pages, pfn_t
*pfns, int *nr)
{
p4d_t *p4d;
unsigned long next;
@@ -204,7 +210,7 @@ static int vmap_p4d_range(pgd_t *pgd, un
return -ENOMEM;
do {
next = p4d_addr_end(addr, end);
- if (vmap_pud_range(p4d, addr, next, prot, pages, nr))
+ if (vmap_pud_range(p4d, addr, next, prot, pages, pfns, nr))
return -ENOMEM;
} while (p4d++, addr = next, addr != end);
return 0;
@@ -217,7 +223,7 @@ static int vmap_p4d_range(pgd_t *pgd, un
* Ie. pte at addr+N*PAGE_SIZE shall point to pfn corresponding to pages[N]
*/
static int vmap_page_range_noflush(unsigned long start, unsigned long end,
- pgprot_t prot, struct page **pages)
+ pgprot_t prot, struct page **pages, pfn_t
*pfns)
{
pgd_t *pgd;
unsigned long next;
@@ -229,7 +235,7 @@ static int vmap_page_range_noflush(unsig
pgd = pgd_offset_k(addr);
do {
next = pgd_addr_end(addr, end);
- err = vmap_p4d_range(pgd, addr, next, prot, pages, &nr);
+ err = vmap_p4d_range(pgd, addr, next, prot, pages, pfns, &nr);
if (err)
return err;
} while (pgd++, addr = next, addr != end);
@@ -238,11 +244,11 @@ static int vmap_page_range_noflush(unsig
}
static int vmap_page_range(unsigned long start, unsigned long end,
- pgprot_t prot, struct page **pages)
+ pgprot_t prot, struct page **pages, pfn_t *pfns)
{
int ret;
- ret = vmap_page_range_noflush(start, end, prot, pages);
+ ret = vmap_page_range_noflush(start, end, prot, pages, pfns);
flush_cache_vmap(start, end);
return ret;
}
@@ -1193,7 +1199,7 @@ void *vm_map_ram(struct page **pages, un
addr = va->va_start;
mem = (void *)addr;
}
- if (vmap_page_range(addr, addr + size, prot, pages) < 0) {
+ if (vmap_page_range(addr, addr + size, prot, pages, NULL) < 0) {
vm_unmap_ram(mem, count);
return NULL;
}
@@ -1308,7 +1314,7 @@ void __init vmalloc_init(void)
int map_kernel_range_noflush(unsigned long addr, unsigned long size,
pgprot_t prot, struct page **pages)
{
- return vmap_page_range_noflush(addr, addr + size, prot, pages);
+ return vmap_page_range_noflush(addr, addr + size, prot, pages, NULL);
}
/**
@@ -1349,13 +1355,24 @@ void unmap_kernel_range(unsigned long ad
}
EXPORT_SYMBOL_GPL(unmap_kernel_range);
+static int map_vm_area_pfn(struct vm_struct *area, pgprot_t prot, pfn_t *pfns)
+{
+ unsigned long addr = (unsigned long)area->addr;
+ unsigned long end = addr + get_vm_area_size(area);
+ int err;
+
+ err = vmap_page_range(addr, end, prot, NULL, pfns);
+
+ return err > 0 ? 0 : err;
+}
+
int map_vm_area(struct vm_struct *area, pgprot_t prot, struct page **pages)
{
unsigned long addr = (unsigned long)area->addr;
unsigned long end = addr + get_vm_area_size(area);
int err;
- err = vmap_page_range(addr, end, prot, pages);
+ err = vmap_page_range(addr, end, prot, pages, NULL);
return err > 0 ? 0 : err;
}
@@ -1662,6 +1679,39 @@ void *vmap(struct page **pages, unsigned
}
EXPORT_SYMBOL(vmap);
+/**
+ * vmap_pfn - map an array of pages into virtually contiguous space
+ * @pfns: array of page frame numbers
+ * @count: number of pages to map
+ * @flags: vm_area->flags
+ * @prot: page protection for the mapping
+ *
+ * Maps @count pages from @pages into contiguous kernel virtual
+ * space.
+ */
+void *vmap_pfn(pfn_t *pfns, unsigned int count, unsigned long flags, pgprot_t
prot)
+{
+ struct vm_struct *area;
+ unsigned long size; /* In bytes */
+
+ might_sleep();
+
+ size = (unsigned long)count << PAGE_SHIFT;
+ if (unlikely((size >> PAGE_SHIFT) != count))
+ return NULL;
+ area = get_vm_area_caller(size, flags, __builtin_return_address(0));
+ if (!area)
+ return NULL;
+
+ if (map_vm_area_pfn(area, prot, pfns)) {
+ vunmap(area->addr);
+ return NULL;
+ }
+
+ return area->addr;
+}
+EXPORT_SYMBOL(vmap_pfn);
+
static void *__vmalloc_node(unsigned long size, unsigned long align,
gfp_t gfp_mask, pgprot_t prot,
int node, const void *caller);
--
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