From c9cfcddfd65735437a4cb8563d6b66a6da8a5ed6 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 29 Nov 2005 14:03:14 -0800 Subject: [PATCH] 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 --- fs/exec.c | 12 +----------- include/linux/mm.h | 2 ++ mm/fremap.c | 24 ++---------------------- mm/memory.c | 26 ++++++++++++++------------ 4 files changed, 19 insertions(+), 45 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index 1f8a9fd2c9e..22533cce061 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -306,9 +306,6 @@ void install_arg_page(struct vm_area_struct *vma, struct page *page, unsigned long address) { struct mm_struct *mm = vma->vm_mm; - pgd_t * pgd; - pud_t * pud; - pmd_t * pmd; pte_t * pte; spinlock_t *ptl; @@ -316,14 +313,7 @@ void install_arg_page(struct vm_area_struct *vma, goto out; flush_dcache_page(page); - pgd = pgd_offset(mm, address); - pud = pud_alloc(mm, pgd, address); - if (!pud) - goto out; - pmd = pmd_alloc(mm, pud, address); - if (!pmd) - goto out; - pte = pte_alloc_map_lock(mm, pmd, address, &ptl); + pte = get_locked_pte(mm, address, &ptl); if (!pte) goto out; if (!pte_none(*pte)) { diff --git a/include/linux/mm.h b/include/linux/mm.h index 74f90d7eb5e..0e73f1539d0 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -742,6 +742,8 @@ struct shrinker; extern struct shrinker *set_shrinker(int, shrinker_t); extern void remove_shrinker(struct shrinker *shrinker); +extern pte_t *FASTCALL(get_locked_pte(struct mm_struct *mm, unsigned long addr, spinlock_t **ptl)); + int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address); int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address); int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address); diff --git a/mm/fremap.c b/mm/fremap.c index f851775e09c..9f381e58bf4 100644 --- a/mm/fremap.c +++ b/mm/fremap.c @@ -55,20 +55,10 @@ int install_page(struct mm_struct *mm, struct vm_area_struct *vma, pgoff_t size; int err = -ENOMEM; pte_t *pte; - pmd_t *pmd; - pud_t *pud; - pgd_t *pgd; pte_t pte_val; spinlock_t *ptl; - pgd = pgd_offset(mm, addr); - pud = pud_alloc(mm, pgd, addr); - if (!pud) - goto out; - pmd = pmd_alloc(mm, pud, addr); - if (!pmd) - goto out; - pte = pte_alloc_map_lock(mm, pmd, addr, &ptl); + pte = get_locked_pte(mm, addr, &ptl); if (!pte) goto out; @@ -110,20 +100,10 @@ int install_file_pte(struct mm_struct *mm, struct vm_area_struct *vma, { int err = -ENOMEM; pte_t *pte; - pmd_t *pmd; - pud_t *pud; - pgd_t *pgd; pte_t pte_val; spinlock_t *ptl; - pgd = pgd_offset(mm, addr); - pud = pud_alloc(mm, pgd, addr); - if (!pud) - goto out; - pmd = pmd_alloc(mm, pud, addr); - if (!pmd) - goto out; - pte = pte_alloc_map_lock(mm, pmd, addr, &ptl); + pte = get_locked_pte(mm, addr, &ptl); if (!pte) goto out; diff --git a/mm/memory.c b/mm/memory.c index 990e7dc666f..74f95ae0510 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1146,6 +1146,18 @@ int zeromap_page_range(struct vm_area_struct *vma, return err; } +pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr, spinlock_t **ptl) +{ + pgd_t * pgd = pgd_offset(mm, addr); + pud_t * pud = pud_alloc(mm, pgd, addr); + if (pud) { + pmd_t * pmd = pmd_alloc(mm, pgd, addr); + if (pmd) + return pte_alloc_map_lock(mm, pmd, addr, ptl); + } + return NULL; +} + /* * This is the old fallback for page remapping. * @@ -1156,10 +1168,7 @@ int zeromap_page_range(struct vm_area_struct *vma, static int insert_page(struct mm_struct *mm, unsigned long addr, struct page *page, pgprot_t prot) { int retval; - pgd_t * pgd; - pud_t * pud; - pmd_t * pmd; - pte_t * pte; + pte_t *pte; spinlock_t *ptl; retval = -EINVAL; @@ -1167,14 +1176,7 @@ static int insert_page(struct mm_struct *mm, unsigned long addr, struct page *pa goto out; retval = -ENOMEM; flush_dcache_page(page); - pgd = pgd_offset(mm, addr); - pud = pud_alloc(mm, pgd, addr); - if (!pud) - goto out; - pmd = pmd_alloc(mm, pud, addr); - if (!pmd) - goto out; - pte = pte_alloc_map_lock(mm, pmd, addr, &ptl); + pte = get_locked_pte(mm, addr, &ptl); if (!pte) goto out; retval = -EBUSY; -- 2.20.1