VM: add common helper function to create the page tables

This logic was duplicated four times, for no good reason.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>

+19 -45
+1 -11
fs/exec.c
··· 306 struct page *page, unsigned long address) 307 { 308 struct mm_struct *mm = vma->vm_mm; 309 - pgd_t * pgd; 310 - pud_t * pud; 311 - pmd_t * pmd; 312 pte_t * pte; 313 spinlock_t *ptl; 314 ··· 313 goto out; 314 315 flush_dcache_page(page); 316 - pgd = pgd_offset(mm, address); 317 - pud = pud_alloc(mm, pgd, address); 318 - if (!pud) 319 - goto out; 320 - pmd = pmd_alloc(mm, pud, address); 321 - if (!pmd) 322 - goto out; 323 - pte = pte_alloc_map_lock(mm, pmd, address, &ptl); 324 if (!pte) 325 goto out; 326 if (!pte_none(*pte)) {
··· 306 struct page *page, unsigned long address) 307 { 308 struct mm_struct *mm = vma->vm_mm; 309 pte_t * pte; 310 spinlock_t *ptl; 311 ··· 316 goto out; 317 318 flush_dcache_page(page); 319 + pte = get_locked_pte(mm, address, &ptl); 320 if (!pte) 321 goto out; 322 if (!pte_none(*pte)) {
+2
include/linux/mm.h
··· 742 extern struct shrinker *set_shrinker(int, shrinker_t); 743 extern void remove_shrinker(struct shrinker *shrinker); 744 745 int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address); 746 int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address); 747 int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address);
··· 742 extern struct shrinker *set_shrinker(int, shrinker_t); 743 extern void remove_shrinker(struct shrinker *shrinker); 744 745 + extern pte_t *FASTCALL(get_locked_pte(struct mm_struct *mm, unsigned long addr, spinlock_t **ptl)); 746 + 747 int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address); 748 int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address); 749 int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address);
+2 -22
mm/fremap.c
··· 55 pgoff_t size; 56 int err = -ENOMEM; 57 pte_t *pte; 58 - pmd_t *pmd; 59 - pud_t *pud; 60 - pgd_t *pgd; 61 pte_t pte_val; 62 spinlock_t *ptl; 63 64 - pgd = pgd_offset(mm, addr); 65 - pud = pud_alloc(mm, pgd, addr); 66 - if (!pud) 67 - goto out; 68 - pmd = pmd_alloc(mm, pud, addr); 69 - if (!pmd) 70 - goto out; 71 - pte = pte_alloc_map_lock(mm, pmd, addr, &ptl); 72 if (!pte) 73 goto out; 74 ··· 100 { 101 int err = -ENOMEM; 102 pte_t *pte; 103 - pmd_t *pmd; 104 - pud_t *pud; 105 - pgd_t *pgd; 106 pte_t pte_val; 107 spinlock_t *ptl; 108 109 - pgd = pgd_offset(mm, addr); 110 - pud = pud_alloc(mm, pgd, addr); 111 - if (!pud) 112 - goto out; 113 - pmd = pmd_alloc(mm, pud, addr); 114 - if (!pmd) 115 - goto out; 116 - pte = pte_alloc_map_lock(mm, pmd, addr, &ptl); 117 if (!pte) 118 goto out; 119
··· 55 pgoff_t size; 56 int err = -ENOMEM; 57 pte_t *pte; 58 pte_t pte_val; 59 spinlock_t *ptl; 60 61 + pte = get_locked_pte(mm, addr, &ptl); 62 if (!pte) 63 goto out; 64 ··· 110 { 111 int err = -ENOMEM; 112 pte_t *pte; 113 pte_t pte_val; 114 spinlock_t *ptl; 115 116 + pte = get_locked_pte(mm, addr, &ptl); 117 if (!pte) 118 goto out; 119
+14 -12
mm/memory.c
··· 1146 return err; 1147 } 1148 1149 /* 1150 * This is the old fallback for page remapping. 1151 * ··· 1168 static int insert_page(struct mm_struct *mm, unsigned long addr, struct page *page, pgprot_t prot) 1169 { 1170 int retval; 1171 - pgd_t * pgd; 1172 - pud_t * pud; 1173 - pmd_t * pmd; 1174 - pte_t * pte; 1175 spinlock_t *ptl; 1176 1177 retval = -EINVAL; ··· 1176 goto out; 1177 retval = -ENOMEM; 1178 flush_dcache_page(page); 1179 - pgd = pgd_offset(mm, addr); 1180 - pud = pud_alloc(mm, pgd, addr); 1181 - if (!pud) 1182 - goto out; 1183 - pmd = pmd_alloc(mm, pud, addr); 1184 - if (!pmd) 1185 - goto out; 1186 - pte = pte_alloc_map_lock(mm, pmd, addr, &ptl); 1187 if (!pte) 1188 goto out; 1189 retval = -EBUSY;
··· 1146 return err; 1147 } 1148 1149 + pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr, spinlock_t **ptl) 1150 + { 1151 + pgd_t * pgd = pgd_offset(mm, addr); 1152 + pud_t * pud = pud_alloc(mm, pgd, addr); 1153 + if (pud) { 1154 + pmd_t * pmd = pmd_alloc(mm, pgd, addr); 1155 + if (pmd) 1156 + return pte_alloc_map_lock(mm, pmd, addr, ptl); 1157 + } 1158 + return NULL; 1159 + } 1160 + 1161 /* 1162 * This is the old fallback for page remapping. 1163 * ··· 1156 static int insert_page(struct mm_struct *mm, unsigned long addr, struct page *page, pgprot_t prot) 1157 { 1158 int retval; 1159 + pte_t *pte; 1160 spinlock_t *ptl; 1161 1162 retval = -EINVAL; ··· 1167 goto out; 1168 retval = -ENOMEM; 1169 flush_dcache_page(page); 1170 + pte = get_locked_pte(mm, addr, &ptl); 1171 if (!pte) 1172 goto out; 1173 retval = -EBUSY;