X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=mm%2Fmincore.c;h=9ac42dc6d7b61481b1eedb8e12b463bd151b1f92;hb=df64f81bb1e01cbef967a96642dacf208acb7e72;hp=a0c4c10bbab7bec64ea525d6e57f51da5aa879c1;hpb=f488401076c5570130c018e573f450a9a6c43365;p=safe%2Fjmp%2Flinux-2.6

diff --git a/mm/mincore.c b/mm/mincore.c
index a0c4c10..9ac42dc 100644
--- a/mm/mincore.c
+++ b/mm/mincore.c
@@ -20,14 +20,12 @@
 #include <asm/pgtable.h>
 
 static void mincore_hugetlb_page_range(struct vm_area_struct *vma,
-				unsigned long addr, unsigned long nr,
+				unsigned long addr, unsigned long end,
 				unsigned char *vec)
 {
 #ifdef CONFIG_HUGETLB_PAGE
 	struct hstate *h;
-	int i;
 
-	i = 0;
 	h = hstate_vma(vma);
 	while (1) {
 		unsigned char present;
@@ -40,10 +38,10 @@ static void mincore_hugetlb_page_range(struct vm_area_struct *vma,
 				       addr & huge_page_mask(h));
 		present = ptep && !huge_pte_none(huge_ptep_get(ptep));
 		while (1) {
-			vec[i++] = present;
+			*vec = present;
+			vec++;
 			addr += PAGE_SIZE;
-			/* reach buffer limit */
-			if (i == nr)
+			if (addr == end)
 				return;
 			/* check hugepage border */
 			if (!(addr & ~huge_page_mask(h)))
@@ -86,9 +84,10 @@ static unsigned char mincore_page(struct address_space *mapping, pgoff_t pgoff)
 }
 
 static void mincore_unmapped_range(struct vm_area_struct *vma,
-				unsigned long addr, unsigned long nr,
+				unsigned long addr, unsigned long end,
 				unsigned char *vec)
 {
+	unsigned long nr = (end - addr) >> PAGE_SHIFT;
 	int i;
 
 	if (vma->vm_file) {
@@ -104,45 +103,101 @@ static void mincore_unmapped_range(struct vm_area_struct *vma,
 }
 
 static void mincore_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
-			unsigned long addr, unsigned long nr,
+			unsigned long addr, unsigned long end,
 			unsigned char *vec)
 {
+	unsigned long next;
 	spinlock_t *ptl;
 	pte_t *ptep;
-	int i;
 
 	ptep = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
-	for (i = 0; i < nr; i++, ptep++, addr += PAGE_SIZE) {
+	do {
 		pte_t pte = *ptep;
 		pgoff_t pgoff;
 
+		next = addr + PAGE_SIZE;
 		if (pte_none(pte))
-			mincore_unmapped_range(vma, addr, 1, vec);
+			mincore_unmapped_range(vma, addr, next, vec);
 		else if (pte_present(pte))
-			vec[i] = 1;
+			*vec = 1;
 		else if (pte_file(pte)) {
 			pgoff = pte_to_pgoff(pte);
-			vec[i] = mincore_page(vma->vm_file->f_mapping, pgoff);
+			*vec = mincore_page(vma->vm_file->f_mapping, pgoff);
 		} else { /* pte is a swap entry */
 			swp_entry_t entry = pte_to_swp_entry(pte);
 
 			if (is_migration_entry(entry)) {
 				/* migration entries are always uptodate */
-				vec[i] = 1;
+				*vec = 1;
 			} else {
 #ifdef CONFIG_SWAP
 				pgoff = entry.val;
-				vec[i] = mincore_page(&swapper_space, pgoff);
+				*vec = mincore_page(&swapper_space, pgoff);
 #else
 				WARN_ON(1);
-				vec[i] = 1;
+				*vec = 1;
 #endif
 			}
 		}
-	}
+		vec++;
+	} while (ptep++, addr = next, addr != end);
 	pte_unmap_unlock(ptep - 1, ptl);
 }
 
+static void mincore_pmd_range(struct vm_area_struct *vma, pud_t *pud,
+			unsigned long addr, unsigned long end,
+			unsigned char *vec)
+{
+	unsigned long next;
+	pmd_t *pmd;
+
+	pmd = pmd_offset(pud, addr);
+	do {
+		next = pmd_addr_end(addr, end);
+		if (pmd_none_or_clear_bad(pmd))
+			mincore_unmapped_range(vma, addr, next, vec);
+		else
+			mincore_pte_range(vma, pmd, addr, next, vec);
+		vec += (next - addr) >> PAGE_SHIFT;
+	} while (pmd++, addr = next, addr != end);
+}
+
+static void mincore_pud_range(struct vm_area_struct *vma, pgd_t *pgd,
+			unsigned long addr, unsigned long end,
+			unsigned char *vec)
+{
+	unsigned long next;
+	pud_t *pud;
+
+	pud = pud_offset(pgd, addr);
+	do {
+		next = pud_addr_end(addr, end);
+		if (pud_none_or_clear_bad(pud))
+			mincore_unmapped_range(vma, addr, next, vec);
+		else
+			mincore_pmd_range(vma, pud, addr, next, vec);
+		vec += (next - addr) >> PAGE_SHIFT;
+	} while (pud++, addr = next, addr != end);
+}
+
+static void mincore_page_range(struct vm_area_struct *vma,
+			unsigned long addr, unsigned long end,
+			unsigned char *vec)
+{
+	unsigned long next;
+	pgd_t *pgd;
+
+	pgd = pgd_offset(vma->vm_mm, addr);
+	do {
+		next = pgd_addr_end(addr, end);
+		if (pgd_none_or_clear_bad(pgd))
+			mincore_unmapped_range(vma, addr, next, vec);
+		else
+			mincore_pud_range(vma, pgd, addr, next, vec);
+		vec += (next - addr) >> PAGE_SHIFT;
+	} while (pgd++, addr = next, addr != end);
+}
+
 /*
  * Do a chunk of "sys_mincore()". We've already checked
  * all the arguments, we hold the mmap semaphore: we should
@@ -150,45 +205,28 @@ static void mincore_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
  */
 static long do_mincore(unsigned long addr, unsigned long pages, unsigned char *vec)
 {
-	pgd_t *pgd;
-	pud_t *pud;
-	pmd_t *pmd;
-	unsigned long nr;
 	struct vm_area_struct *vma;
+	unsigned long end;
 
 	vma = find_vma(current->mm, addr);
 	if (!vma || addr < vma->vm_start)
 		return -ENOMEM;
 
-	nr = min(pages, (vma->vm_end - addr) >> PAGE_SHIFT);
+	end = min(vma->vm_end, addr + (pages << PAGE_SHIFT));
 
 	if (is_vm_hugetlb_page(vma)) {
-		mincore_hugetlb_page_range(vma, addr, nr, vec);
-		return nr;
+		mincore_hugetlb_page_range(vma, addr, end, vec);
+		return (end - addr) >> PAGE_SHIFT;
 	}
 
-	/*
-	 * Calculate how many pages there are left in the last level of the
-	 * PTE array for our address.
-	 */
-	nr = min(nr, PTRS_PER_PTE - ((addr >> PAGE_SHIFT) & (PTRS_PER_PTE-1)));
-
-	pgd = pgd_offset(vma->vm_mm, addr);
-	if (pgd_none_or_clear_bad(pgd))
-		goto none_mapped;
-	pud = pud_offset(pgd, addr);
-	if (pud_none_or_clear_bad(pud))
-		goto none_mapped;
-	pmd = pmd_offset(pud, addr);
-	if (pmd_none_or_clear_bad(pmd))
-		goto none_mapped;
+	end = pmd_addr_end(addr, end);
 
-	mincore_pte_range(vma, pmd, addr, nr, vec);
-	return nr;
+	if (is_vm_hugetlb_page(vma))
+		mincore_hugetlb_page_range(vma, addr, end, vec);
+	else
+		mincore_page_range(vma, addr, end, vec);
 
-none_mapped:
-	mincore_unmapped_range(vma, addr, nr, vec);
-	return nr;
+	return (end - addr) >> PAGE_SHIFT;
 }
 
 /*