[PATCH 3/4] vmemmap: pull out the vmemmap code into its own file

Andy Whitcroft
2007-08-02T09:25:35Z

Pull out the SPARSEMEM_VMEMMAP support into its own file.

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
---
include/linux/mm.h | 1 +
mm/Makefile | 1 +
mm/sparse-vmemmap.c | 181 +++++++++++++++++++++++++++++++++++++++++++++++++++
mm/sparse.c | 180 +--------------------------------------------------
4 files changed, 185 insertions(+), 178 deletions(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 22e9705..9ea07a5 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1211,6 +1211,7 @@ extern int randomize_va_space;

const char * arch_vma_name(struct vm_area_struct *vma);

+struct page *sparse_early_mem_map_populate(unsigned long pnum, int nid);
int vmemmap_populate(struct page *start_page, unsigned long pages, int node);
int vmemmap_populate_pmd(pud_t *, unsigned long, unsigned long, int);
void *vmemmap_alloc_block(unsigned long size, int node);
diff --git a/mm/Makefile b/mm/Makefile
index 3dd262a..adb8442 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -19,6 +19,7 @@ obj-$(CONFIG_SWAP_PREFETCH) += swap_prefetch.o
obj-$(CONFIG_HUGETLBFS) += hugetlb.o
obj-$(CONFIG_NUMA) += mempolicy.o
obj-$(CONFIG_SPARSEMEM) += sparse.o
+obj-$(CONFIG_SPARSEMEM_VMEMMAP) += sparse-vmemmap.o
obj-$(CONFIG_SHMEM) += shmem.o
obj-$(CONFIG_TMPFS_POSIX_ACL) += shmem_acl.o
obj-$(CONFIG_TINY_SHMEM) += tiny-shmem.o
diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
new file mode 100644
index 0000000..7bb7a4b
--- /dev/null
+++ b/mm/sparse-vmemmap.c
@@ -0,0 +1,181 @@
+/*
+ * Virtual Memory Map support
+ *
+ * (C) 2007 sgi. Christoph Lameter <clameter@sgi.com>.
+ *
+ * Virtual memory maps allow VM primitives pfn_to_page, page_to_pfn,
+ * virt_to_page, page_address() to be implemented as a base offset
+ * calculation without memory access.
+ *
+ * However, virtual mappings need a page table and TLBs. Many Linux
+ * architectures already map their physical space using 1-1 mappings
+ * via TLBs. For those arches the virtual memmory map is essentially
+ * for free if we use the same page size as the 1-1 mappings. In that
+ * case the overhead consists of a few additional pages that are
+ * allocated to create a view of memory for vmemmap.
+ *
+ * Special Kconfig settings:
+ *
+ * CONFIG_ARCH_POPULATES_SPARSEMEM_VMEMMAP
+ *
+ * The architecture has its own functions to populate the memory
+ * map and provides a vmemmap_populate function.
+ *
+ * CONFIG_ARCH_POPULATES_SPARSEMEM_VMEMMAP_PMD
+ *
+ * The architecture provides functions to populate the pmd level
+ * of the vmemmap mappings. Allowing mappings using large pages
+ * where available.
+ *
+ * If neither are set then PAGE_SIZE mappings are generated which
+ * require one PTE/TLB per PAGE_SIZE chunk of the virtual memory map.
+ */
+#include <linux/mm.h>
+#include <linux/mmzone.h>
+#include <linux/bootmem.h>
+#include <linux/highmem.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/vmalloc.h>
+#include <asm/dma.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+
+/*
+ * Allocate a block of memory to be used to back the virtual memory map
+ * or to back the page tables that are used to create the mapping.
+ * Uses the main allocators if they are available, else bootmem.
+ */
+void * __meminit vmemmap_alloc_block(unsigned long size, int node)
+{
+ /* If the main allocator is up use that, fallback to bootmem. */
+ if (slab_is_available()) {
+ struct page *page = alloc_pages_node(node,
+ GFP_KERNEL | __GFP_ZERO, get_order(size));
+ if (page)
+ return page_address(page);
+ return NULL;
+ } else
+ return __alloc_bootmem_node(NODE_DATA(node), size, size,
+ __pa(MAX_DMA_ADDRESS));
+}
+
+#ifndef CONFIG_ARCH_POPULATES_SPARSEMEM_VMEMMAP
+void __meminit vmemmap_verify(pte_t *pte, int node,
+ unsigned long start, unsigned long end)
+{
+ unsigned long pfn = pte_pfn(*pte);
+ int actual_node = early_pfn_to_nid(pfn);
+
+ if (actual_node != node)
+ printk(KERN_WARNING "[%lx-%lx] potential offnode "
+ "page_structs\n", start, end - 1);
+}
+
+#ifndef CONFIG_ARCH_POPULATES_SPARSEMEM_VMEMMAP_PMD
+static int __meminit vmemmap_populate_pte(pmd_t *pmd, unsigned long addr,
+ unsigned long end, int node)
+{
+ pte_t *pte;
+
+ for (pte = pte_offset_kernel(pmd, addr); addr < end;
+ pte++, addr += PAGE_SIZE)
+ if (pte_none(*pte)) {
+ pte_t entry;
+ void *p = vmemmap_alloc_block(PAGE_SIZE, node);
+ if (!p)
+ return -ENOMEM;
+
+ entry = pfn_pte(__pa(p) >> PAGE_SHIFT, PAGE_KERNEL);
+ set_pte(pte, entry);
+
+ } else
+ vmemmap_verify(pte, node, addr + PAGE_SIZE, end);
+
+ return 0;
+}
+
+int __meminit vmemmap_populate_pmd(pud_t *pud, unsigned long addr,
+ unsigned long end, int node)
+{
+ pmd_t *pmd;
+ int error = 0;
+ unsigned long next;
+
+ for (pmd = pmd_offset(pud, addr); addr < end && !error;
+ pmd++, addr = next) {
+ if (pmd_none(*pmd)) {
+ void *p = vmemmap_alloc_block(PAGE_SIZE, node);
+ if (!p)
+ return -ENOMEM;
+
+ pmd_populate_kernel(&init_mm, pmd, p);
+ } else
+ vmemmap_verify((pte_t *)pmd, node,
+ pmd_addr_end(addr, end), end);
+ next = pmd_addr_end(addr, end);
+ error = vmemmap_populate_pte(pmd, addr, next, node);
+ }
+ return error;
+}
+#endif /* CONFIG_ARCH_POPULATES_SPARSEMEM_VMEMMAP_PMD */
+
+static int __meminit vmemmap_populate_pud(pgd_t *pgd, unsigned long addr,
+ unsigned long end, int node)
+{
+ pud_t *pud;
+ int error = 0;
+ unsigned long next;
+
+ for (pud = pud_offset(pgd, addr); addr < end && !error;
+ pud++, addr = next) {
+ if (pud_none(*pud)) {
+ void *p = vmemmap_alloc_block(PAGE_SIZE, node);
+ if (!p)
+ return -ENOMEM;
+
+ pud_populate(&init_mm, pud, p);
+ }
+ next = pud_addr_end(addr, end);
+ error = vmemmap_populate_pmd(pud, addr, next, node);
+ }
+ return error;
+}
+
+int __meminit vmemmap_populate(struct page *start_page,
+ unsigned long nr, int node)
+{
+ pgd_t *pgd;
+ unsigned long addr = (unsigned long)start_page;
+ unsigned long end = (unsigned long)(start_page + nr);
+ unsigned long next;
+ int error = 0;
+
+ printk(KERN_DEBUG "[%lx-%lx] Virtual memory section"
+ " (%ld pages) node %d\n", addr, end - 1, nr, node);
+
+ for (pgd = pgd_offset_k(addr); addr < end && !error;
+ pgd++, addr = next) {
+ if (pgd_none(*pgd)) {
+ void *p = vmemmap_alloc_block(PAGE_SIZE, node);
+ if (!p)
+ return -ENOMEM;
+
+ pgd_populate(&init_mm, pgd, p);
+ }
+ next = pgd_addr_end(addr,end);
+ error = vmemmap_populate_pud(pgd, addr, next, node);
+ }
+ return error;
+}
+#endif /* !CONFIG_ARCH_POPULATES_SPARSEMEM_VMEMMAP */
+
+struct page __init *sparse_early_mem_map_populate(unsigned long pnum, int nid)
+{
+ struct page *map = pfn_to_page(pnum * PAGES_PER_SECTION);
+ int error = vmemmap_populate(map, PAGES_PER_SECTION, nid);
+ if (error)
+ return NULL;
+
+ return map;
+}
diff --git a/mm/sparse.c b/mm/sparse.c
index 1905759..1f4dbb8 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -258,184 +258,8 @@ static unsigned long *sparse_early_usemap_alloc(unsigned long pnum)
return NULL;
}

-#ifdef CONFIG_SPARSEMEM_VMEMMAP
-/*
- * Virtual Memory Map support
- *
- * (C) 2007 sgi. Christoph Lameter <clameter@sgi.com>.
- *
- * Virtual memory maps allow VM primitives pfn_to_page, page_to_pfn,
- * virt_to_page, page_address() to be implemented as a base offset
- * calculation without memory access.
- *
- * However, virtual mappings need a page table and TLBs. Many Linux
- * architectures already map their physical space using 1-1 mappings
- * via TLBs. For those arches the virtual memmory map is essentially
- * for free if we use the same page size as the 1-1 mappings. In that
- * case the overhead consists of a few additional pages that are
- * allocated to create a view of memory for vmemmap.
- *
- * Special Kconfig settings:
- *
- * CONFIG_ARCH_POPULATES_SPARSEMEM_VMEMMAP
- *
- * The architecture has its own functions to populate the memory
- * map and provides a vmemmap_populate function.
- *
- * CONFIG_ARCH_POPULATES_SPARSEMEM_VMEMMAP_PMD
- *
- * The architecture provides functions to populate the pmd level
- * of the vmemmap mappings. Allowing mappings using large pages
- * where available.
- *
- * If neither are set then PAGE_SIZE mappings are generated which
- * require one PTE/TLB per PAGE_SIZE chunk of the virtual memory map.
- */
-
-/*
- * Allocate a block of memory to be used to back the virtual memory map
- * or to back the page tables that are used to create the mapping.
- * Uses the main allocators if they are available, else bootmem.
- */
-void * __meminit vmemmap_alloc_block(unsigned long size, int node)
-{
- /* If the main allocator is up use that, fallback to bootmem. */
- if (slab_is_available()) {
- struct page *page = alloc_pages_node(node,
- GFP_KERNEL | __GFP_ZERO, get_order(size));
- if (page)
- return page_address(page);
- return NULL;
- } else
- return __alloc_bootmem_node(NODE_DATA(node), size, size,
- __pa(MAX_DMA_ADDRESS));
-}
-
-#ifndef CONFIG_ARCH_POPULATES_SPARSEMEM_VMEMMAP
-void __meminit vmemmap_verify(pte_t *pte, int node,
- unsigned long start, unsigned long end)
-{
- unsigned long pfn = pte_pfn(*pte);
- int actual_node = early_pfn_to_nid(pfn);
-
- if (actual_node != node)
- printk(KERN_WARNING "[%lx-%lx] potential offnode "
- "page_structs\n", start, end - 1);
-}
-
-#ifndef CONFIG_ARCH_POPULATES_SPARSEMEM_VMEMMAP_PMD
-static int __meminit vmemmap_populate_pte(pmd_t *pmd, unsigned long addr,
- unsigned long end, int node)
-{
- pte_t *pte;
-
- for (pte = pte_offset_kernel(pmd, addr); addr < end;
- pte++, addr += PAGE_SIZE)
- if (pte_none(*pte)) {
- pte_t entry;
- void *p = vmemmap_alloc_block(PAGE_SIZE, node);
- if (!p)
- return -ENOMEM;
-
- entry = pfn_pte(__pa(p) >> PAGE_SHIFT, PAGE_KERNEL);
- set_pte(pte, entry);
-
- } else
- vmemmap_verify(pte, node, addr + PAGE_SIZE, end);
-
- return 0;
-}
-
-int __meminit vmemmap_populate_pmd(pud_t *pud, unsigned long addr,
- unsigned long end, int node)
-{
- pmd_t *pmd;
- int error = 0;
- unsigned long next;
-
- for (pmd = pmd_offset(pud, addr); addr < end && !error;
- pmd++, addr = next) {
- if (pmd_none(*pmd)) {
- void *p = vmemmap_alloc_block(PAGE_SIZE, node);
- if (!p)
- return -ENOMEM;
-
- pmd_populate_kernel(&init_mm, pmd, p);
- } else
- vmemmap_verify((pte_t *)pmd, node,
- pmd_addr_end(addr, end), end);
- next = pmd_addr_end(addr, end);
- error = vmemmap_populate_pte(pmd, addr, next, node);
- }
- return error;
-}
-#endif /* CONFIG_ARCH_POPULATES_SPARSEMEM_VMEMMAP_PMD */
-
-static int __meminit vmemmap_populate_pud(pgd_t *pgd, unsigned long addr,
- unsigned long end, int node)
-{
- pud_t *pud;
- int error = 0;
- unsigned long next;
-
- for (pud = pud_offset(pgd, addr); addr < end && !error;
- pud++, addr = next) {
- if (pud_none(*pud)) {
- void *p = vmemmap_alloc_block(PAGE_SIZE, node);
- if (!p)
- return -ENOMEM;
-
- pud_populate(&init_mm, pud, p);
- }
- next = pud_addr_end(addr, end);
- error = vmemmap_populate_pmd(pud, addr, next, node);
- }
- return error;
-}
-
-int __meminit vmemmap_populate(struct page *start_page,
- unsigned long nr, int node)
-{
- pgd_t *pgd;
- unsigned long addr = (unsigned long)start_page;
- unsigned long end = (unsigned long)(start_page + nr);
- unsigned long next;
- int error = 0;
-
- printk(KERN_DEBUG "[%lx-%lx] Virtual memory section"
- " (%ld pages) node %d\n", addr, end - 1, nr, node);
-
- for (pgd = pgd_offset_k(addr); addr < end && !error;
- pgd++, addr = next) {
- if (pgd_none(*pgd)) {
- void *p = vmemmap_alloc_block(PAGE_SIZE, node);
- if (!p)
- return -ENOMEM;
-
- pgd_populate(&init_mm, pgd, p);
- }
- next = pgd_addr_end(addr,end);
- error = vmemmap_populate_pud(pgd, addr, next, node);
- }
- return error;
-}
-#endif /* !CONFIG_ARCH_POPULATES_SPARSEMEM_VMEMMAP */
-
-static struct page __init *sparse_early_mem_map_populate(unsigned long pnum,
- int nid)
-{
- struct page *map = pfn_to_page(pnum * PAGES_PER_SECTION);
- int error = vmemmap_populate(map, PAGES_PER_SECTION, nid);
- if (error)
- return NULL;
-
- return map;
-}
-
-#else /* CONFIG_SPARSEMEM_VMEMMAP */
-
-static struct page __init *sparse_early_mem_map_populate(unsigned long pnum,
- int nid)
+#ifndef CONFIG_SPARSEMEM_VMEMMAP
+struct page __init *sparse_early_mem_map_populate(unsigned long pnum, int nid)
{
struct page *map;