From: Nicholas Piggin <npiggin-AT-gmail.com>
ascend inclusion category: feature bugzilla: NA CVE: NA
https://lwn.net/ml/linux-kernel/20200825145753.529284-10-npiggin@gmail.com/ --------------
This is a generic kernel virtual memory mapper, not specific to ioremap.
Signed-off-by: Nicholas Piggin npiggin@gmail.com Signed-off-by: Rui Xiang rui.xiang@huawei.com Reviewed-by: Ding Tianhong dingtianhong@huawei.com Reviewed-by: Zefan Li lizefan@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- include/linux/vmalloc.h | 3 + mm/ioremap.c | 176 ---------------------------------------- mm/vmalloc.c | 175 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 178 insertions(+), 176 deletions(-)
diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h index 6cbbebc97ea8..496ac80046c0 100644 --- a/include/linux/vmalloc.h +++ b/include/linux/vmalloc.h @@ -147,6 +147,9 @@ extern struct vm_struct *remove_vm_area(const void *addr); extern struct vm_struct *find_vm_area(const void *addr);
#ifdef CONFIG_MMU +int vmap_range(unsigned long addr, unsigned long end, + phys_addr_t phys_addr, pgprot_t prot, + unsigned int max_page_shift); extern int map_kernel_range_noflush(unsigned long start, unsigned long size, pgprot_t prot, struct page **pages); int map_kernel_range(unsigned long start, unsigned long size, pgprot_t prot, diff --git a/mm/ioremap.c b/mm/ioremap.c index e4c5044b1ab2..8b1905bf03d2 100644 --- a/mm/ioremap.c +++ b/mm/ioremap.c @@ -27,182 +27,6 @@ early_param("nohugeiomap", set_nohugeiomap); static const bool iomap_max_page_shift = PAGE_SHIFT; #endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
-static int vmap_pte_range(pmd_t *pmd, unsigned long addr, - unsigned long end, phys_addr_t phys_addr, pgprot_t prot) -{ - pte_t *pte; - u64 pfn; - - pfn = phys_addr >> PAGE_SHIFT; - pte = pte_alloc_kernel(pmd, addr); - if (!pte) - return -ENOMEM; - do { - BUG_ON(!pte_none(*pte)); - set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot)); - pfn++; - } while (pte++, addr += PAGE_SIZE, addr != end); - return 0; -} - -static int vmap_try_huge_pmd(pmd_t *pmd, unsigned long addr, unsigned long end, - phys_addr_t phys_addr, pgprot_t prot, - unsigned int max_page_shift) -{ - if (max_page_shift < PMD_SHIFT) - return 0; - - if (!arch_vmap_pmd_supported(prot)) - return 0; - - if ((end - addr) != PMD_SIZE) - return 0; - - if (!IS_ALIGNED(phys_addr, PMD_SIZE)) - return 0; - - if (pmd_present(*pmd) && !pmd_free_pte_page(pmd, addr)) - return 0; - - return pmd_set_huge(pmd, phys_addr, prot); -} - -static int vmap_pmd_range(pud_t *pud, unsigned long addr, - unsigned long end, phys_addr_t phys_addr, pgprot_t prot, - unsigned int max_page_shift) -{ - pmd_t *pmd; - unsigned long next; - - pmd = pmd_alloc(&init_mm, pud, addr); - if (!pmd) - return -ENOMEM; - do { - next = pmd_addr_end(addr, end); - - if (vmap_try_huge_pmd(pmd, addr, next, phys_addr, prot, max_page_shift)) - continue; - - if (vmap_pte_range(pmd, addr, next, phys_addr, prot)) - return -ENOMEM; - } while (pmd++, phys_addr += (next - addr), addr = next, addr != end); - return 0; -} - -static int vmap_try_huge_pud(pud_t *pud, unsigned long addr, unsigned long end, - phys_addr_t phys_addr, pgprot_t prot, - unsigned int max_page_shift) -{ - if (max_page_shift < PUD_SHIFT) - return 0; - - if (!arch_vmap_pud_supported(prot)) - return 0; - - if ((end - addr) != PUD_SIZE) - return 0; - - if (!IS_ALIGNED(phys_addr, PUD_SIZE)) - return 0; - - if (pud_present(*pud) && !pud_free_pmd_page(pud, addr)) - return 0; - - return pud_set_huge(pud, phys_addr, prot); -} - -static int vmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end, - phys_addr_t phys_addr, pgprot_t prot, - unsigned int max_page_shift) -{ - pud_t *pud; - unsigned long next; - - pud = pud_alloc(&init_mm, p4d, addr); - if (!pud) - return -ENOMEM; - do { - next = pud_addr_end(addr, end); - - if (vmap_try_huge_pud(pud, addr, next, phys_addr, prot, max_page_shift)) - continue; - - if (vmap_pmd_range(pud, addr, next, phys_addr, prot, max_page_shift)) - return -ENOMEM; - } while (pud++, phys_addr += (next - addr), addr = next, addr != end); - return 0; -} - -static int vmap_try_huge_p4d(p4d_t *p4d, unsigned long addr, unsigned long end, - phys_addr_t phys_addr, pgprot_t prot, - unsigned int max_page_shift) -{ - if (max_page_shift < P4D_SHIFT) - return 0; - - if (!arch_vmap_p4d_supported(prot)) - return 0; - - if ((end - addr) != P4D_SIZE) - return 0; - - if (!IS_ALIGNED(phys_addr, P4D_SIZE)) - return 0; - - if (p4d_present(*p4d) && !p4d_free_pud_page(p4d, addr)) - return 0; - - return p4d_set_huge(p4d, phys_addr, prot); -} - -static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end, - phys_addr_t phys_addr, pgprot_t prot, - unsigned int max_page_shift) -{ - p4d_t *p4d; - unsigned long next; - - p4d = p4d_alloc(&init_mm, pgd, addr); - if (!p4d) - return -ENOMEM; - do { - next = p4d_addr_end(addr, end); - - if (vmap_try_huge_p4d(p4d, addr, next, phys_addr, prot, max_page_shift)) - continue; - - if (vmap_pud_range(p4d, addr, next, phys_addr, prot, max_page_shift)) - return -ENOMEM; - } while (p4d++, phys_addr += (next - addr), addr = next, addr != end); - return 0; -} - -static int vmap_range(unsigned long addr, unsigned long end, - phys_addr_t phys_addr, pgprot_t prot, - unsigned int max_page_shift) -{ - pgd_t *pgd; - unsigned long start; - unsigned long next; - int err; - - might_sleep(); - BUG_ON(addr >= end); - - start = addr; - pgd = pgd_offset_k(addr); - do { - next = pgd_addr_end(addr, end); - err = vmap_p4d_range(pgd, addr, next, phys_addr, prot, max_page_shift); - if (err) - break; - } while (pgd++, phys_addr += (next - addr), addr = next, addr != end); - - flush_cache_vmap(start, end); - - return err; -} - int ioremap_page_range(unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot) { diff --git a/mm/vmalloc.c b/mm/vmalloc.c index c0dd884d65cd..b9bc49565252 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -59,6 +59,181 @@ static void free_work(struct work_struct *w) }
/*** Page table manipulation functions ***/ +static int vmap_pte_range(pmd_t *pmd, unsigned long addr, + unsigned long end, phys_addr_t phys_addr, pgprot_t prot) +{ + pte_t *pte; + u64 pfn; + + pfn = phys_addr >> PAGE_SHIFT; + pte = pte_alloc_kernel(pmd, addr); + if (!pte) + return -ENOMEM; + do { + BUG_ON(!pte_none(*pte)); + set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot)); + pfn++; + } while (pte++, addr += PAGE_SIZE, addr != end); + return 0; +} + +static int vmap_try_huge_pmd(pmd_t *pmd, unsigned long addr, unsigned long end, + phys_addr_t phys_addr, pgprot_t prot, + unsigned int max_page_shift) +{ + if (max_page_shift < PMD_SHIFT) + return 0; + + if (!arch_vmap_pmd_supported(prot)) + return 0; + + if ((end - addr) != PMD_SIZE) + return 0; + + if (!IS_ALIGNED(phys_addr, PMD_SIZE)) + return 0; + + if (pmd_present(*pmd) && !pmd_free_pte_page(pmd, addr)) + return 0; + + return pmd_set_huge(pmd, phys_addr, prot); +} + +static int vmap_pmd_range(pud_t *pud, unsigned long addr, + unsigned long end, phys_addr_t phys_addr, pgprot_t prot, + unsigned int max_page_shift) +{ + pmd_t *pmd; + unsigned long next; + + pmd = pmd_alloc(&init_mm, pud, addr); + if (!pmd) + return -ENOMEM; + do { + next = pmd_addr_end(addr, end); + + if (vmap_try_huge_pmd(pmd, addr, next, phys_addr, prot, max_page_shift)) + continue; + + if (vmap_pte_range(pmd, addr, next, phys_addr, prot)) + return -ENOMEM; + } while (pmd++, phys_addr += (next - addr), addr = next, addr != end); + return 0; +} + +static int vmap_try_huge_pud(pud_t *pud, unsigned long addr, unsigned long end, + phys_addr_t phys_addr, pgprot_t prot, + unsigned int max_page_shift) +{ + if (max_page_shift < PUD_SHIFT) + return 0; + + if (!arch_vmap_pud_supported(prot)) + return 0; + + if ((end - addr) != PUD_SIZE) + return 0; + + if (!IS_ALIGNED(phys_addr, PUD_SIZE)) + return 0; + + if (pud_present(*pud) && !pud_free_pmd_page(pud, addr)) + return 0; + + return pud_set_huge(pud, phys_addr, prot); +} + +static int vmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end, + phys_addr_t phys_addr, pgprot_t prot, + unsigned int max_page_shift) +{ + pud_t *pud; + unsigned long next; + + pud = pud_alloc(&init_mm, p4d, addr); + if (!pud) + return -ENOMEM; + do { + next = pud_addr_end(addr, end); + + if (vmap_try_huge_pud(pud, addr, next, phys_addr, prot, max_page_shift)) + continue; + + if (vmap_pmd_range(pud, addr, next, phys_addr, prot, max_page_shift)) + return -ENOMEM; + } while (pud++, phys_addr += (next - addr), addr = next, addr != end); + return 0; +} + +static int vmap_try_huge_p4d(p4d_t *p4d, unsigned long addr, unsigned long end, + phys_addr_t phys_addr, pgprot_t prot, + unsigned int max_page_shift) +{ + if (max_page_shift < P4D_SHIFT) + return 0; + + if (!arch_vmap_p4d_supported(prot)) + return 0; + + if ((end - addr) != P4D_SIZE) + return 0; + + if (!IS_ALIGNED(phys_addr, P4D_SIZE)) + return 0; + + if (p4d_present(*p4d) && !p4d_free_pud_page(p4d, addr)) + return 0; + + return p4d_set_huge(p4d, phys_addr, prot); +} + +static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end, + phys_addr_t phys_addr, pgprot_t prot, + unsigned int max_page_shift) +{ + p4d_t *p4d; + unsigned long next; + + p4d = p4d_alloc(&init_mm, pgd, addr); + if (!p4d) + return -ENOMEM; + do { + next = p4d_addr_end(addr, end); + + if (vmap_try_huge_p4d(p4d, addr, next, phys_addr, prot, max_page_shift)) + continue; + + if (vmap_pud_range(p4d, addr, next, phys_addr, prot, max_page_shift)) + return -ENOMEM; + } while (p4d++, phys_addr += (next - addr), addr = next, addr != end); + return 0; +} + +int vmap_range(unsigned long addr, unsigned long end, + phys_addr_t phys_addr, pgprot_t prot, + unsigned int max_page_shift) +{ + pgd_t *pgd; + unsigned long start; + unsigned long next; + int err; + + might_sleep(); + BUG_ON(addr >= end); + + start = addr; + pgd = pgd_offset_k(addr); + do { + next = pgd_addr_end(addr, end); + err = vmap_p4d_range(pgd, addr, next, phys_addr, prot, max_page_shift); + if (err) + break; + } while (pgd++, phys_addr += (next - addr), addr = next, addr != end); + + flush_cache_vmap(start, end); + + return err; +}
static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end) {