Re: [PATCH V1 09/10] arch/kmap: Define kmap_atomic_prot() for all arch's

From: Christoph Hellwig
Date: Fri May 01 2020 - 04:48:14 EST


On Thu, Apr 30, 2020 at 01:38:44PM -0700, ira.weiny@xxxxxxxxx wrote:
> From: Ira Weiny <ira.weiny@xxxxxxxxx>
>
> To support kmap_atomic_prot(), all architectures need to support
> protections passed to their kmap_atomic_high() function. Pass
> protections into kmap_atomic_high() and change the name to
> kmap_atomic_high_prot() to match.
>
> Then define kmap_atomic_prot() as a core function which calls
> kmap_atomic_high_prot() when needed.
>
> Finally, redefine kmap_atomic() as a wrapper of kmap_atomic_prot() with
> the default kmap_prot exported by the architectures.

Looks good,

Reviewed-by: Christoph Hellwig <hch@xxxxxx>

But can you also consolidate the kmap_atomic_high_prot and
kunmap_atomic_high in linux/highmem.h instead of keeping the duplicates
in all arch headers?

>
> Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>
> ---
> arch/arc/include/asm/highmem.h | 2 +-
> arch/arc/mm/highmem.c | 6 +++---
> arch/arm/include/asm/highmem.h | 2 +-
> arch/arm/mm/highmem.c | 6 +++---
> arch/csky/include/asm/highmem.h | 2 +-
> arch/csky/mm/highmem.c | 6 +++---
> arch/microblaze/include/asm/highmem.h | 7 +------
> arch/microblaze/mm/highmem.c | 4 ++--
> arch/mips/include/asm/highmem.h | 2 +-
> arch/mips/mm/highmem.c | 6 +++---
> arch/nds32/include/asm/highmem.h | 2 +-
> arch/nds32/mm/highmem.c | 6 +++---
> arch/powerpc/include/asm/highmem.h | 8 +-------
> arch/powerpc/mm/highmem.c | 4 ++--
> arch/sparc/include/asm/highmem.h | 2 +-
> arch/sparc/mm/highmem.c | 6 +++---
> arch/x86/include/asm/highmem.h | 6 +-----
> arch/x86/mm/highmem_32.c | 4 ++--
> arch/xtensa/include/asm/highmem.h | 2 +-
> arch/xtensa/mm/highmem.c | 6 +++---
> include/linux/highmem.h | 5 +++--
> 21 files changed, 40 insertions(+), 54 deletions(-)
>
> diff --git a/arch/arc/include/asm/highmem.h b/arch/arc/include/asm/highmem.h
> index e16531495620..09f86bde6809 100644
> --- a/arch/arc/include/asm/highmem.h
> +++ b/arch/arc/include/asm/highmem.h
> @@ -30,7 +30,7 @@
>
> #include <asm/cacheflush.h>
>
> -extern void *kmap_atomic_high(struct page *page);
> +extern void *kmap_atomic_high_prot(struct page *page, pgprot_t prot);
> extern void kunmap_atomic_high(void *kvaddr);
>
> extern void kmap_init(void);
> diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c
> index 5d3eab4ac0b0..479b0d72d3cf 100644
> --- a/arch/arc/mm/highmem.c
> +++ b/arch/arc/mm/highmem.c
> @@ -49,7 +49,7 @@
> extern pte_t * pkmap_page_table;
> static pte_t * fixmap_page_table;
>
> -void *kmap_atomic_high(struct page *page)
> +void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
> {
> int idx, cpu_idx;
> unsigned long vaddr;
> @@ -59,11 +59,11 @@ void *kmap_atomic_high(struct page *page)
> vaddr = FIXMAP_ADDR(idx);
>
> set_pte_at(&init_mm, vaddr, fixmap_page_table + idx,
> - mk_pte(page, kmap_prot));
> + mk_pte(page, prot));
>
> return (void *)vaddr;
> }
> -EXPORT_SYMBOL(kmap_atomic_high);
> +EXPORT_SYMBOL(kmap_atomic_high_prot);
>
> void kunmap_atomic_high(void *kv)
> {
> diff --git a/arch/arm/include/asm/highmem.h b/arch/arm/include/asm/highmem.h
> index a9d5e9bce1cc..e35f2f73f6aa 100644
> --- a/arch/arm/include/asm/highmem.h
> +++ b/arch/arm/include/asm/highmem.h
> @@ -60,7 +60,7 @@ static inline void *kmap_high_get(struct page *page)
> * when CONFIG_HIGHMEM is not set.
> */
> #ifdef CONFIG_HIGHMEM
> -extern void *kmap_atomic_high(struct page *page);
> +extern void *kmap_atomic_high_prot(struct page *page, pgprot_t prot);
> extern void kunmap_atomic_high(void *kvaddr);
> extern void *kmap_atomic_pfn(unsigned long pfn);
> #endif
> diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c
> index ac8394655a6e..e013f6b81328 100644
> --- a/arch/arm/mm/highmem.c
> +++ b/arch/arm/mm/highmem.c
> @@ -31,7 +31,7 @@ static inline pte_t get_fixmap_pte(unsigned long vaddr)
> return *ptep;
> }
>
> -void *kmap_atomic_high(struct page *page)
> +void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
> {
> unsigned int idx;
> unsigned long vaddr;
> @@ -67,11 +67,11 @@ void *kmap_atomic_high(struct page *page)
> * in place, so the contained TLB flush ensures the TLB is updated
> * with the new mapping.
> */
> - set_fixmap_pte(idx, mk_pte(page, kmap_prot));
> + set_fixmap_pte(idx, mk_pte(page, prot));
>
> return (void *)vaddr;
> }
> -EXPORT_SYMBOL(kmap_atomic_high);
> +EXPORT_SYMBOL(kmap_atomic_high_prot);
>
> void kunmap_atomic_high(void *kvaddr)
> {
> diff --git a/arch/csky/include/asm/highmem.h b/arch/csky/include/asm/highmem.h
> index 5bbbe59e60a9..59854c7ccf78 100644
> --- a/arch/csky/include/asm/highmem.h
> +++ b/arch/csky/include/asm/highmem.h
> @@ -32,7 +32,7 @@ extern pte_t *pkmap_page_table;
>
> #define ARCH_HAS_KMAP_FLUSH_TLB
> extern void kmap_flush_tlb(unsigned long addr);
> -extern void *kmap_atomic_high(struct page *page);
> +extern void *kmap_atomic_high_prot(struct page *page, pgprot_t prot);
> extern void kunmap_atomic_high(void *kvaddr);
> extern void *kmap_atomic_pfn(unsigned long pfn);
> extern struct page *kmap_atomic_to_page(void *ptr);
> diff --git a/arch/csky/mm/highmem.c b/arch/csky/mm/highmem.c
> index f4311669b5bb..3ae5c8cd7619 100644
> --- a/arch/csky/mm/highmem.c
> +++ b/arch/csky/mm/highmem.c
> @@ -21,7 +21,7 @@ EXPORT_SYMBOL(kmap_flush_tlb);
>
> EXPORT_SYMBOL(kmap);
>
> -void *kmap_atomic_high(struct page *page)
> +void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
> {
> unsigned long vaddr;
> int idx, type;
> @@ -32,12 +32,12 @@ void *kmap_atomic_high(struct page *page)
> #ifdef CONFIG_DEBUG_HIGHMEM
> BUG_ON(!pte_none(*(kmap_pte - idx)));
> #endif
> - set_pte(kmap_pte-idx, mk_pte(page, kmap_prot));
> + set_pte(kmap_pte-idx, mk_pte(page, prot));
> flush_tlb_one((unsigned long)vaddr);
>
> return (void *)vaddr;
> }
> -EXPORT_SYMBOL(kmap_atomic_high);
> +EXPORT_SYMBOL(kmap_atomic_high_prot);
>
> void kunmap_atomic_high(void *kvaddr)
> {
> diff --git a/arch/microblaze/include/asm/highmem.h b/arch/microblaze/include/asm/highmem.h
> index 66521fdc3a47..eb0a2cb883bd 100644
> --- a/arch/microblaze/include/asm/highmem.h
> +++ b/arch/microblaze/include/asm/highmem.h
> @@ -51,14 +51,9 @@ extern pte_t *pkmap_page_table;
> #define PKMAP_NR(virt) ((virt - PKMAP_BASE) >> PAGE_SHIFT)
> #define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
>
> -extern void *kmap_atomic_prot(struct page *page, pgprot_t prot);
> +extern void *kmap_atomic_high_prot(struct page *page, pgprot_t prot);
> extern void kunmap_atomic_high(void *kvaddr);
>
> -static inline void *kmap_atomic_high(struct page *page)
> -{
> - return kmap_atomic_prot(page, kmap_prot);
> -}
> -
> #define flush_cache_kmaps() { flush_icache(); flush_dcache(); }
>
> #endif /* __KERNEL__ */
> diff --git a/arch/microblaze/mm/highmem.c b/arch/microblaze/mm/highmem.c
> index 1026aeffe11a..ee8a422b2b76 100644
> --- a/arch/microblaze/mm/highmem.c
> +++ b/arch/microblaze/mm/highmem.c
> @@ -32,7 +32,7 @@
> */
> #include <asm/tlbflush.h>
>
> -void *kmap_atomic_prot(struct page *page, pgprot_t prot)
> +void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
> {
>
> unsigned long vaddr;
> @@ -49,7 +49,7 @@ void *kmap_atomic_prot(struct page *page, pgprot_t prot)
>
> return (void *) vaddr;
> }
> -EXPORT_SYMBOL(kmap_atomic_prot);
> +EXPORT_SYMBOL(kmap_atomic_high_prot);
>
> void kunmap_atomic_high(void *kvaddr)
> {
> diff --git a/arch/mips/include/asm/highmem.h b/arch/mips/include/asm/highmem.h
> index d9f774bd4938..c9f46b450a68 100644
> --- a/arch/mips/include/asm/highmem.h
> +++ b/arch/mips/include/asm/highmem.h
> @@ -48,7 +48,7 @@ extern pte_t *pkmap_page_table;
>
> #define ARCH_HAS_KMAP_FLUSH_TLB
> extern void kmap_flush_tlb(unsigned long addr);
> -extern void *kmap_atomic_high(struct page *page);
> +extern void *kmap_atomic_high_prot(struct page *page, pgprot_t prot);
> extern void kunmap_atomic_high(void *kvaddr);
> extern void *kmap_atomic_pfn(unsigned long pfn);
>
> diff --git a/arch/mips/mm/highmem.c b/arch/mips/mm/highmem.c
> index 87023bd1a33c..37e244cdb14e 100644
> --- a/arch/mips/mm/highmem.c
> +++ b/arch/mips/mm/highmem.c
> @@ -18,7 +18,7 @@ void kmap_flush_tlb(unsigned long addr)
> }
> EXPORT_SYMBOL(kmap_flush_tlb);
>
> -void *kmap_atomic_high(struct page *page)
> +void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
> {
> unsigned long vaddr;
> int idx, type;
> @@ -29,12 +29,12 @@ void *kmap_atomic_high(struct page *page)
> #ifdef CONFIG_DEBUG_HIGHMEM
> BUG_ON(!pte_none(*(kmap_pte - idx)));
> #endif
> - set_pte(kmap_pte-idx, mk_pte(page, kmap_prot));
> + set_pte(kmap_pte-idx, mk_pte(page, prot));
> local_flush_tlb_one((unsigned long)vaddr);
>
> return (void*) vaddr;
> }
> -EXPORT_SYMBOL(kmap_atomic_high);
> +EXPORT_SYMBOL(kmap_atomic_high_prot);
>
> void kunmap_atomic_high(void *kvaddr)
> {
> diff --git a/arch/nds32/include/asm/highmem.h b/arch/nds32/include/asm/highmem.h
> index 97648b678108..1f9fc74d112d 100644
> --- a/arch/nds32/include/asm/highmem.h
> +++ b/arch/nds32/include/asm/highmem.h
> @@ -51,7 +51,7 @@ extern void kmap_init(void);
> * when CONFIG_HIGHMEM is not set.
> */
> #ifdef CONFIG_HIGHMEM
> -extern void *kmap_atomic_high(struct page *page);
> +extern void *kmap_atomic_high_prot(struct page *page, pgprot_t prot);
> extern void kunmap_atomic_high(void *kvaddr);
> extern void *kmap_atomic_pfn(unsigned long pfn);
> extern struct page *kmap_atomic_to_page(void *ptr);
> diff --git a/arch/nds32/mm/highmem.c b/arch/nds32/mm/highmem.c
> index 809f8c830f06..63ded527c1e8 100644
> --- a/arch/nds32/mm/highmem.c
> +++ b/arch/nds32/mm/highmem.c
> @@ -10,7 +10,7 @@
> #include <asm/fixmap.h>
> #include <asm/tlbflush.h>
>
> -void *kmap_atomic_high(struct page *page)
> +void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
> {
> unsigned int idx;
> unsigned long vaddr, pte;
> @@ -21,7 +21,7 @@ void *kmap_atomic_high(struct page *page)
>
> idx = type + KM_TYPE_NR * smp_processor_id();
> vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
> - pte = (page_to_pfn(page) << PAGE_SHIFT) | (kmap_prot);
> + pte = (page_to_pfn(page) << PAGE_SHIFT) | prot;
> ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
> set_pte(ptep, pte);
>
> @@ -32,7 +32,7 @@ void *kmap_atomic_high(struct page *page)
> return (void *)vaddr;
> }
>
> -EXPORT_SYMBOL(kmap_atomic_high);
> +EXPORT_SYMBOL(kmap_atomic_high_prot);
>
> void kunmap_atomic_high(void *kvaddr)
> {
> diff --git a/arch/powerpc/include/asm/highmem.h b/arch/powerpc/include/asm/highmem.h
> index d264aebcaa9b..edd01bbe5a44 100644
> --- a/arch/powerpc/include/asm/highmem.h
> +++ b/arch/powerpc/include/asm/highmem.h
> @@ -59,15 +59,9 @@ extern pte_t *pkmap_page_table;
> #define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT)
> #define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
>
> -extern void *kmap_atomic_prot(struct page *page, pgprot_t prot);
> +extern void *kmap_atomic_high_prot(struct page *page, pgprot_t prot);
> extern void kunmap_atomic_high(void *kvaddr);
>
> -static inline void *kmap_atomic_high(struct page *page)
> -{
> - return kmap_atomic_prot(page, kmap_prot);
> -}
> -
> -
> #define flush_cache_kmaps() flush_cache_all()
>
> #endif /* __KERNEL__ */
> diff --git a/arch/powerpc/mm/highmem.c b/arch/powerpc/mm/highmem.c
> index 162958321e28..35071c2913f1 100644
> --- a/arch/powerpc/mm/highmem.c
> +++ b/arch/powerpc/mm/highmem.c
> @@ -24,7 +24,7 @@
> #include <linux/highmem.h>
> #include <linux/module.h>
>
> -void *kmap_atomic_prot(struct page *page, pgprot_t prot)
> +void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
> {
> unsigned long vaddr;
> int idx, type;
> @@ -38,7 +38,7 @@ void *kmap_atomic_prot(struct page *page, pgprot_t prot)
>
> return (void*) vaddr;
> }
> -EXPORT_SYMBOL(kmap_atomic_prot);
> +EXPORT_SYMBOL(kmap_atomic_high_prot);
>
> void kunmap_atomic_high(void *kvaddr)
> {
> diff --git a/arch/sparc/include/asm/highmem.h b/arch/sparc/include/asm/highmem.h
> index 94dd6e4c5fa4..d5c5700672de 100644
> --- a/arch/sparc/include/asm/highmem.h
> +++ b/arch/sparc/include/asm/highmem.h
> @@ -50,7 +50,7 @@ void kmap_init(void) __init;
>
> #define PKMAP_END (PKMAP_ADDR(LAST_PKMAP))
>
> -void *kmap_atomic_high(struct page *page);
> +void *kmap_atomic_high_prot(struct page *page, pgprot_t prot);
> void kunmap_atomic_high(void *kvaddr);
>
> #define flush_cache_kmaps() flush_cache_all()
> diff --git a/arch/sparc/mm/highmem.c b/arch/sparc/mm/highmem.c
> index 9f06d75e88e1..414f578d1e57 100644
> --- a/arch/sparc/mm/highmem.c
> +++ b/arch/sparc/mm/highmem.c
> @@ -54,7 +54,7 @@ void __init kmap_init(void)
> kmap_prot = __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE);
> }
>
> -void *kmap_atomic_high(struct page *page)
> +void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
> {
> unsigned long vaddr;
> long idx, type;
> @@ -73,7 +73,7 @@ void *kmap_atomic_high(struct page *page)
> #ifdef CONFIG_DEBUG_HIGHMEM
> BUG_ON(!pte_none(*(kmap_pte-idx)));
> #endif
> - set_pte(kmap_pte-idx, mk_pte(page, kmap_prot));
> + set_pte(kmap_pte-idx, mk_pte(page, prot));
> /* XXX Fix - Anton */
> #if 0
> __flush_tlb_one(vaddr);
> @@ -83,7 +83,7 @@ void *kmap_atomic_high(struct page *page)
>
> return (void*) vaddr;
> }
> -EXPORT_SYMBOL(kmap_atomic_high);
> +EXPORT_SYMBOL(kmap_atomic_high_prot);
>
> void kunmap_atomic_high(void *kvaddr)
> {
> diff --git a/arch/x86/include/asm/highmem.h b/arch/x86/include/asm/highmem.h
> index ff87aba96eee..009b8e22e906 100644
> --- a/arch/x86/include/asm/highmem.h
> +++ b/arch/x86/include/asm/highmem.h
> @@ -58,11 +58,7 @@ extern unsigned long highstart_pfn, highend_pfn;
> #define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT)
> #define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
>
> -extern void *kmap_atomic_prot(struct page *page, pgprot_t prot);
> -void *kmap_atomic_high(struct page *page)
> -{
> - return kmap_atomic_prot(page, kmap_prot);
> -}
> +void *kmap_atomic_high_prot(struct page *page, pgprot_t prot);
> void kunmap_atomic_high(void *kvaddr);
> void *kmap_atomic_pfn(unsigned long pfn);
> void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot);
> diff --git a/arch/x86/mm/highmem_32.c b/arch/x86/mm/highmem_32.c
> index af07a6842743..075fe51317b0 100644
> --- a/arch/x86/mm/highmem_32.c
> +++ b/arch/x86/mm/highmem_32.c
> @@ -4,7 +4,7 @@
> #include <linux/swap.h> /* for totalram_pages */
> #include <linux/memblock.h>
>
> -void *kmap_atomic_prot(struct page *page, pgprot_t prot)
> +void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
> {
> unsigned long vaddr;
> int idx, type;
> @@ -18,7 +18,7 @@ void *kmap_atomic_prot(struct page *page, pgprot_t prot)
>
> return (void *)vaddr;
> }
> -EXPORT_SYMBOL(kmap_atomic_prot);
> +EXPORT_SYMBOL(kmap_atomic_high_prot);
>
> /*
> * This is the same as kmap_atomic() but can map memory that doesn't
> diff --git a/arch/xtensa/include/asm/highmem.h b/arch/xtensa/include/asm/highmem.h
> index a60a02dc68f6..7152aeb1e3a4 100644
> --- a/arch/xtensa/include/asm/highmem.h
> +++ b/arch/xtensa/include/asm/highmem.h
> @@ -68,7 +68,7 @@ static inline void flush_cache_kmaps(void)
> flush_cache_all();
> }
>
> -void *kmap_atomic_high(struct page *page);
> +void *kmap_atomic_high_prot(struct page *page, pgprot_t prot);
> void kunmap_atomic_high(void *kvaddr);
>
> void kmap_init(void);
> diff --git a/arch/xtensa/mm/highmem.c b/arch/xtensa/mm/highmem.c
> index 8c58c4c37033..fe56644d7b23 100644
> --- a/arch/xtensa/mm/highmem.c
> +++ b/arch/xtensa/mm/highmem.c
> @@ -37,7 +37,7 @@ static inline enum fixed_addresses kmap_idx(int type, unsigned long color)
> color;
> }
>
> -void *kmap_atomic_high(struct page *page)
> +void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
> {
> enum fixed_addresses idx;
> unsigned long vaddr;
> @@ -48,11 +48,11 @@ void *kmap_atomic_high(struct page *page)
> #ifdef CONFIG_DEBUG_HIGHMEM
> BUG_ON(!pte_none(*(kmap_pte + idx)));
> #endif
> - set_pte(kmap_pte + idx, mk_pte(page, kmap_prot));
> + set_pte(kmap_pte + idx, mk_pte(page, prot));
>
> return (void *)vaddr;
> }
> -EXPORT_SYMBOL(kmap_atomic_high);
> +EXPORT_SYMBOL(kmap_atomic_high_prot);
>
> void kunmap_atomic_high(void *kvaddr)
> {
> diff --git a/include/linux/highmem.h b/include/linux/highmem.h
> index 601df07607a4..b10e8a39ae60 100644
> --- a/include/linux/highmem.h
> +++ b/include/linux/highmem.h
> @@ -74,14 +74,15 @@ static inline void kunmap(struct page *page)
> * be used in IRQ contexts, so in some (very limited) cases we need
> * it.
> */
> -static inline void *kmap_atomic(struct page *page)
> +static inline void *kmap_atomic_prot(struct page *page, pgprot_t prot)
> {
> preempt_disable();
> pagefault_disable();
> if (!PageHighMem(page))
> return page_address(page);
> - return kmap_atomic_high(page);
> + return kmap_atomic_high_prot(page, prot);
> }
> +#define kmap_atomic(page) kmap_atomic_prot(page, kmap_prot)
>
> /* declarations for linux/mm/highmem.c */
> unsigned int nr_free_highpages(void);
> --
> 2.25.1
>
---end quoted text---