[PATCH v4 6/8] mm: Move vmap_range from lib/ioremap.c to mm/vmalloc.c

From: Nicholas Piggin
Date: Sun Aug 16 2020 - 05:10:03 EST


This is a generic kernel virtual memory mapper, not specific to ioremap.

Signed-off-by: Nicholas Piggin <npiggin@xxxxxxxxx>
---
include/linux/vmalloc.h | 2 +
mm/ioremap.c | 192 ----------------------------------------
mm/vmalloc.c | 191 +++++++++++++++++++++++++++++++++++++++
3 files changed, 193 insertions(+), 192 deletions(-)

diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 787d77ad7536..e3590e93bfff 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -181,6 +181,8 @@ extern struct vm_struct *remove_vm_area(const void *addr);
extern struct vm_struct *find_vm_area(const void *addr);

#ifdef CONFIG_MMU
+extern 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 b0032dbadaf7..cdda0e022740 100644
--- a/mm/ioremap.c
+++ b/mm/ioremap.c
@@ -28,198 +28,6 @@ early_param("nohugeiomap", set_nohugeiomap);
static const bool iomap_allow_huge = false;
#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, pgtbl_mod_mask *mask)
-{
- pte_t *pte;
- u64 pfn;
-
- pfn = phys_addr >> PAGE_SHIFT;
- pte = pte_alloc_kernel_track(pmd, addr, mask);
- 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);
- *mask |= PGTBL_PTE_MODIFIED;
- 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(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,
- pgtbl_mod_mask *mask)
-{
- pmd_t *pmd;
- unsigned long next;
-
- pmd = pmd_alloc_track(&init_mm, pud, addr, mask);
- 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)) {
- *mask |= PGTBL_PMD_MODIFIED;
- continue;
- }
-
- if (vmap_pte_range(pmd, addr, next, phys_addr, prot, mask))
- 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(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,
- pgtbl_mod_mask *mask)
-{
- pud_t *pud;
- unsigned long next;
-
- pud = pud_alloc_track(&init_mm, p4d, addr, mask);
- 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)) {
- *mask |= PGTBL_PUD_MODIFIED;
- continue;
- }
-
- if (vmap_pmd_range(pud, addr, next, phys_addr, prot, max_page_shift, mask))
- 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(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,
- pgtbl_mod_mask *mask)
-{
- p4d_t *p4d;
- unsigned long next;
-
- p4d = p4d_alloc_track(&init_mm, pgd, addr, mask);
- 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)) {
- *mask |= PGTBL_P4D_MODIFIED;
- continue;
- }
-
- if (vmap_pud_range(p4d, addr, next, phys_addr, prot, max_page_shift, mask))
- 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;
- pgtbl_mod_mask mask = 0;
-
- 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, &mask);
- if (err)
- break;
- } while (pgd++, phys_addr += (next - addr), addr = next, addr != end);
-
- flush_cache_vmap(start, end);
-
- if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
- arch_sync_kernel_mappings(start, end);
-
- return err;
-}
-
int ioremap_page_range(unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
{
unsigned int max_page_shift = PAGE_SHIFT;
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 3a1e45fd1626..129f10545bb1 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -71,6 +71,197 @@ 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, pgtbl_mod_mask *mask)
+{
+ pte_t *pte;
+ u64 pfn;
+
+ pfn = phys_addr >> PAGE_SHIFT;
+ pte = pte_alloc_kernel_track(pmd, addr, mask);
+ 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);
+ *mask |= PGTBL_PTE_MODIFIED;
+ 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(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,
+ pgtbl_mod_mask *mask)
+{
+ pmd_t *pmd;
+ unsigned long next;
+
+ pmd = pmd_alloc_track(&init_mm, pud, addr, mask);
+ 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)) {
+ *mask |= PGTBL_PMD_MODIFIED;
+ continue;
+ }
+
+ if (vmap_pte_range(pmd, addr, next, phys_addr, prot, mask))
+ 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(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,
+ pgtbl_mod_mask *mask)
+{
+ pud_t *pud;
+ unsigned long next;
+
+ pud = pud_alloc_track(&init_mm, p4d, addr, mask);
+ 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)) {
+ *mask |= PGTBL_PUD_MODIFIED;
+ continue;
+ }
+
+ if (vmap_pmd_range(pud, addr, next, phys_addr, prot, max_page_shift, mask))
+ 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(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,
+ pgtbl_mod_mask *mask)
+{
+ p4d_t *p4d;
+ unsigned long next;
+
+ p4d = p4d_alloc_track(&init_mm, pgd, addr, mask);
+ 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)) {
+ *mask |= PGTBL_P4D_MODIFIED;
+ continue;
+ }
+
+ if (vmap_pud_range(p4d, addr, next, phys_addr, prot, max_page_shift, mask))
+ 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;
+ pgtbl_mod_mask mask = 0;
+
+ 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, &mask);
+ if (err)
+ break;
+ } while (pgd++, phys_addr += (next - addr), addr = next, addr != end);
+
+ flush_cache_vmap(start, end);
+
+ if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
+ arch_sync_kernel_mappings(start, end);
+
+ return err;
+}

static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
pgtbl_mod_mask *mask)
--
2.23.0