From: Roland Dreier Date: Sat, 29 Oct 2005 00:46:18 +0000 (-0700) Subject: [PATCH] ppc: make phys_mem_access_prot() work with pfns instead of addresses X-Git-Tag: v2.6.15-rc1~59^2~51 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8b150478aeb1a8edb9015c2f7ac4da637ff65c45;p=linux-2.6 [PATCH] ppc: make phys_mem_access_prot() work with pfns instead of addresses Change the phys_mem_access_prot() function to take a pfn instead of an address. This allows mmap64() to work on /dev/mem for addresses above 4G on 32-bit architectures. We start with a pfn in mmap_mem(), so there's no need to convert to an address; in fact, it's actively bad, since the conversion can overflow when the address is above 4G. Similarly fix the ppc32 page_is_ram() function to avoid a conversion to an address by directly comparing to max_pfn. Working with max_pfn instead of high_memory fixes page_is_ram() to give the right answer for highmem pages. Signed-off-by: Roland Dreier Cc: Anton Blanchard Cc: Benjamin Herrenschmidt Signed-off-by: Andrew Morton Signed-off-by: Paul Mackerras --- diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index 695db6a588..3ca331728d 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -88,13 +88,13 @@ int page_is_ram(unsigned long pfn) } EXPORT_SYMBOL(page_is_ram); -pgprot_t phys_mem_access_prot(struct file *file, unsigned long addr, +pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, unsigned long size, pgprot_t vma_prot) { if (ppc_md.phys_mem_access_prot) - return ppc_md.phys_mem_access_prot(file, addr, size, vma_prot); + return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot); - if (!page_is_ram(addr >> PAGE_SHIFT)) + if (!page_is_ram(pfn)) vma_prot = __pgprot(pgprot_val(vma_prot) | _PAGE_GUARDED | _PAGE_NO_CACHE); return vma_prot; diff --git a/arch/ppc/kernel/pci.c b/arch/ppc/kernel/pci.c index ad4ef2aaa6..e8f4e57675 100644 --- a/arch/ppc/kernel/pci.c +++ b/arch/ppc/kernel/pci.c @@ -1594,16 +1594,17 @@ static pgprot_t __pci_mmap_set_pgprot(struct pci_dev *dev, struct resource *rp, * above routine */ pgprot_t pci_phys_mem_access_prot(struct file *file, - unsigned long offset, + unsigned long pfn, unsigned long size, pgprot_t protection) { struct pci_dev *pdev = NULL; struct resource *found = NULL; unsigned long prot = pgprot_val(protection); + unsigned long offset = pfn << PAGE_SHIFT; int i; - if (page_is_ram(offset >> PAGE_SHIFT)) + if (page_is_ram(pfn)) return prot; prot |= _PAGE_NO_CACHE | _PAGE_GUARDED; diff --git a/arch/ppc/mm/init.c b/arch/ppc/mm/init.c index db94efd253..99b48abd32 100644 --- a/arch/ppc/mm/init.c +++ b/arch/ppc/mm/init.c @@ -637,18 +637,16 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, */ int page_is_ram(unsigned long pfn) { - unsigned long paddr = (pfn << PAGE_SHIFT); - - return paddr < __pa(high_memory); + return pfn < max_pfn; } -pgprot_t phys_mem_access_prot(struct file *file, unsigned long addr, +pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, unsigned long size, pgprot_t vma_prot) { if (ppc_md.phys_mem_access_prot) - return ppc_md.phys_mem_access_prot(file, addr, size, vma_prot); + return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot); - if (!page_is_ram(addr >> PAGE_SHIFT)) + if (!page_is_ram(pfn)) vma_prot = __pgprot(pgprot_val(vma_prot) | _PAGE_GUARDED | _PAGE_NO_CACHE); return vma_prot; diff --git a/arch/ppc64/kernel/pci.c b/arch/ppc64/kernel/pci.c index b2fb6746f0..3d2106b022 100644 --- a/arch/ppc64/kernel/pci.c +++ b/arch/ppc64/kernel/pci.c @@ -726,16 +726,17 @@ static pgprot_t __pci_mmap_set_pgprot(struct pci_dev *dev, struct resource *rp, * above routine */ pgprot_t pci_phys_mem_access_prot(struct file *file, - unsigned long offset, + unsigned long pfn, unsigned long size, pgprot_t protection) { struct pci_dev *pdev = NULL; struct resource *found = NULL; unsigned long prot = pgprot_val(protection); + unsigned long offset = pfn << PAGE_SHIFT; int i; - if (page_is_ram(offset >> PAGE_SHIFT)) + if (page_is_ram(pfn)) return __pgprot(prot); prot |= _PAGE_NO_CACHE | _PAGE_GUARDED; diff --git a/drivers/char/mem.c b/drivers/char/mem.c index f182752fe9..9df928d4f6 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -231,9 +231,7 @@ static ssize_t write_mem(struct file * file, const char __user * buf, static int mmap_mem(struct file * file, struct vm_area_struct * vma) { #if defined(__HAVE_PHYS_MEM_ACCESS_PROT) - unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; - - vma->vm_page_prot = phys_mem_access_prot(file, offset, + vma->vm_page_prot = phys_mem_access_prot(file, vma->vm_pgoff, vma->vm_end - vma->vm_start, vma->vm_page_prot); #elif defined(pgprot_noncached) diff --git a/drivers/video/fbmem.c b/drivers/video/fbmem.c index 70be7009f8..ca02aa2bfc 100644 --- a/drivers/video/fbmem.c +++ b/drivers/video/fbmem.c @@ -918,7 +918,7 @@ fb_mmap(struct file *file, struct vm_area_struct * vma) } #endif #elif defined(__powerpc__) - vma->vm_page_prot = phys_mem_access_prot(file, off, + vma->vm_page_prot = phys_mem_access_prot(file, off >> PAGE_SHIFT, vma->vm_end - vma->vm_start, vma->vm_page_prot); #elif defined(__alpha__) diff --git a/include/asm-powerpc/machdep.h b/include/asm-powerpc/machdep.h index 706508b1b0..451b345cfc 100644 --- a/include/asm-powerpc/machdep.h +++ b/include/asm-powerpc/machdep.h @@ -144,7 +144,7 @@ struct machdep_calls { /* Get access protection for /dev/mem */ pgprot_t (*phys_mem_access_prot)(struct file *file, - unsigned long offset, + unsigned long pfn, unsigned long size, pgprot_t vma_prot); diff --git a/include/asm-ppc/machdep.h b/include/asm-ppc/machdep.h index 6c6d23abbe..f01255bd1d 100644 --- a/include/asm-ppc/machdep.h +++ b/include/asm-ppc/machdep.h @@ -98,7 +98,7 @@ struct machdep_calls { /* Get access protection for /dev/mem */ pgprot_t (*phys_mem_access_prot)(struct file *file, - unsigned long offset, + unsigned long pfn, unsigned long size, pgprot_t vma_prot); diff --git a/include/asm-ppc/pci.h b/include/asm-ppc/pci.h index 643740dd72..61434edbad 100644 --- a/include/asm-ppc/pci.h +++ b/include/asm-ppc/pci.h @@ -126,7 +126,7 @@ extern void pcibios_add_platform_entries(struct pci_dev *dev); struct file; extern pgprot_t pci_phys_mem_access_prot(struct file *file, - unsigned long offset, + unsigned long pfn, unsigned long size, pgprot_t prot); diff --git a/include/asm-ppc/pgtable.h b/include/asm-ppc/pgtable.h index eee601bb9a..b28a713ba8 100644 --- a/include/asm-ppc/pgtable.h +++ b/include/asm-ppc/pgtable.h @@ -705,7 +705,7 @@ static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry, int dirty) #define pgprot_noncached(prot) (__pgprot(pgprot_val(prot) | _PAGE_NO_CACHE | _PAGE_GUARDED)) struct file; -extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long addr, +extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, unsigned long size, pgprot_t vma_prot); #define __HAVE_PHYS_MEM_ACCESS_PROT diff --git a/include/asm-ppc64/pci.h b/include/asm-ppc64/pci.h index a88bbfc269..342e2d7555 100644 --- a/include/asm-ppc64/pci.h +++ b/include/asm-ppc64/pci.h @@ -168,7 +168,7 @@ extern void pcibios_add_platform_entries(struct pci_dev *dev); struct file; extern pgprot_t pci_phys_mem_access_prot(struct file *file, - unsigned long offset, + unsigned long pfn, unsigned long size, pgprot_t prot); diff --git a/include/asm-ppc64/pgtable.h b/include/asm-ppc64/pgtable.h index c83679c9d2..8cf5991540 100644 --- a/include/asm-ppc64/pgtable.h +++ b/include/asm-ppc64/pgtable.h @@ -471,7 +471,7 @@ static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry, int dirty) #define pgprot_noncached(prot) (__pgprot(pgprot_val(prot) | _PAGE_NO_CACHE | _PAGE_GUARDED)) struct file; -extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long addr, +extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, unsigned long size, pgprot_t vma_prot); #define __HAVE_PHYS_MEM_ACCESS_PROT