From 5899329b19100c0b82dc78e9b21ed8b920c9ffb3 Mon Sep 17 00:00:00 2001 From: "venkatesh.pallipadi@intel.com" Date: Thu, 18 Dec 2008 11:41:30 -0800 Subject: x86: PAT: implement track/untrack of pfnmap regions for x86 - v3 Impact: New mm functionality. Hookup remap_pfn_range and vm_insert_pfn and corresponding copy and free routines with reserve and free tracking. reserve and free here only takes care of non RAM region mapping. For RAM region, driver should use set_memory_[uc|wc|wb] to set the cache type and then setup the mapping for user pte. We can bypass below reserve/free in that case. Signed-off-by: Venkatesh Pallipadi Signed-off-by: Suresh Siddha Signed-off-by: H. Peter Anvin --- arch/x86/mm/pat.c | 236 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 236 insertions(+) (limited to 'arch/x86/mm/pat.c') diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c index eb1bf000d12..1069ffecf77 100644 --- a/arch/x86/mm/pat.c +++ b/arch/x86/mm/pat.c @@ -596,6 +596,242 @@ void unmap_devmem(unsigned long pfn, unsigned long size, pgprot_t vma_prot) free_memtype(addr, addr + size); } +/* + * Internal interface to reserve a range of physical memory with prot. + * Reserved non RAM regions only and after successful reserve_memtype, + * this func also keeps identity mapping (if any) in sync with this new prot. + */ +static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t vma_prot) +{ + int is_ram = 0; + int id_sz, ret; + unsigned long flags; + unsigned long want_flags = (pgprot_val(vma_prot) & _PAGE_CACHE_MASK); + + is_ram = pagerange_is_ram(paddr, paddr + size); + + if (is_ram != 0) { + /* + * For mapping RAM pages, drivers need to call + * set_memory_[uc|wc|wb] directly, for reserve and free, before + * setting up the PTE. + */ + WARN_ON_ONCE(1); + return 0; + } + + ret = reserve_memtype(paddr, paddr + size, want_flags, &flags); + if (ret) + return ret; + + if (flags != want_flags) { + free_memtype(paddr, paddr + size); + printk(KERN_ERR + "%s:%d map pfn expected mapping type %s for %Lx-%Lx, got %s\n", + current->comm, current->pid, + cattr_name(want_flags), + (unsigned long long)paddr, + (unsigned long long)(paddr + size), + cattr_name(flags)); + return -EINVAL; + } + + /* Need to keep identity mapping in sync */ + if (paddr >= __pa(high_memory)) + return 0; + + id_sz = (__pa(high_memory) < paddr + size) ? + __pa(high_memory) - paddr : + size; + + if (ioremap_change_attr((unsigned long)__va(paddr), id_sz, flags) < 0) { + free_memtype(paddr, paddr + size); + printk(KERN_ERR + "%s:%d reserve_pfn_range ioremap_change_attr failed %s " + "for %Lx-%Lx\n", + current->comm, current->pid, + cattr_name(flags), + (unsigned long long)paddr, + (unsigned long long)(paddr + size)); + return -EINVAL; + } + return 0; +} + +/* + * Internal interface to free a range of physical memory. + * Frees non RAM regions only. + */ +static void free_pfn_range(u64 paddr, unsigned long size) +{ + int is_ram; + + is_ram = pagerange_is_ram(paddr, paddr + size); + if (is_ram == 0) + free_memtype(paddr, paddr + size); +} + +/* + * track_pfn_vma_copy is called when vma that is covering the pfnmap gets + * copied through copy_page_range(). + * + * If the vma has a linear pfn mapping for the entire range, we get the prot + * from pte and reserve the entire vma range with single reserve_pfn_range call. + * Otherwise, we reserve the entire vma range, my ging through the PTEs page + * by page to get physical address and protection. + */ +int track_pfn_vma_copy(struct vm_area_struct *vma) +{ + int retval = 0; + unsigned long i, j; + u64 paddr; + pgprot_t prot; + pte_t pte; + unsigned long vma_start = vma->vm_start; + unsigned long vma_end = vma->vm_end; + unsigned long vma_size = vma_end - vma_start; + + if (!pat_enabled) + return 0; + + if (is_linear_pfn_mapping(vma)) { + /* + * reserve the whole chunk starting from vm_pgoff, + * But, we have to get the protection from pte. + */ + if (follow_pfnmap_pte(vma, vma_start, &pte)) { + WARN_ON_ONCE(1); + return -1; + } + prot = pte_pgprot(pte); + paddr = (u64)vma->vm_pgoff << PAGE_SHIFT; + return reserve_pfn_range(paddr, vma_size, prot); + } + + /* reserve entire vma page by page, using pfn and prot from pte */ + for (i = 0; i < vma_size; i += PAGE_SIZE) { + if (follow_pfnmap_pte(vma, vma_start + i, &pte)) + continue; + + paddr = pte_pa(pte); + prot = pte_pgprot(pte); + retval = reserve_pfn_range(paddr, PAGE_SIZE, prot); + if (retval) + goto cleanup_ret; + } + return 0; + +cleanup_ret: + /* Reserve error: Cleanup partial reservation and return error */ + for (j = 0; j < i; j += PAGE_SIZE) { + if (follow_pfnmap_pte(vma, vma_start + j, &pte)) + continue; + + paddr = pte_pa(pte); + free_pfn_range(paddr, PAGE_SIZE); + } + + return retval; +} + +/* + * track_pfn_vma_new is called when a _new_ pfn mapping is being established + * for physical range indicated by pfn and size. + * + * prot is passed in as a parameter for the new mapping. If the vma has a + * linear pfn mapping for the entire range reserve the entire vma range with + * single reserve_pfn_range call. + * Otherwise, we look t the pfn and size and reserve only the specified range + * page by page. + * + * Note that this function can be called with caller trying to map only a + * subrange/page inside the vma. + */ +int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t prot, + unsigned long pfn, unsigned long size) +{ + int retval = 0; + unsigned long i, j; + u64 base_paddr; + u64 paddr; + unsigned long vma_start = vma->vm_start; + unsigned long vma_end = vma->vm_end; + unsigned long vma_size = vma_end - vma_start; + + if (!pat_enabled) + return 0; + + if (is_linear_pfn_mapping(vma)) { + /* reserve the whole chunk starting from vm_pgoff */ + paddr = (u64)vma->vm_pgoff << PAGE_SHIFT; + return reserve_pfn_range(paddr, vma_size, prot); + } + + /* reserve page by page using pfn and size */ + base_paddr = (u64)pfn << PAGE_SHIFT; + for (i = 0; i < size; i += PAGE_SIZE) { + paddr = base_paddr + i; + retval = reserve_pfn_range(paddr, PAGE_SIZE, prot); + if (retval) + goto cleanup_ret; + } + return 0; + +cleanup_ret: + /* Reserve error: Cleanup partial reservation and return error */ + for (j = 0; j < i; j += PAGE_SIZE) { + paddr = base_paddr + j; + free_pfn_range(paddr, PAGE_SIZE); + } + + return retval; +} + +/* + * untrack_pfn_vma is called while unmapping a pfnmap for a region. + * untrack can be called for a specific region indicated by pfn and size or + * can be for the entire vma (in which case size can be zero). + */ +void untrack_pfn_vma(struct vm_area_struct *vma, unsigned long pfn, + unsigned long size) +{ + unsigned long i; + u64 paddr; + unsigned long vma_start = vma->vm_start; + unsigned long vma_end = vma->vm_end; + unsigned long vma_size = vma_end - vma_start; + + if (!pat_enabled) + return; + + if (is_linear_pfn_mapping(vma)) { + /* free the whole chunk starting from vm_pgoff */ + paddr = (u64)vma->vm_pgoff << PAGE_SHIFT; + free_pfn_range(paddr, vma_size); + return; + } + + if (size != 0 && size != vma_size) { + /* free page by page, using pfn and size */ + paddr = (u64)pfn << PAGE_SHIFT; + for (i = 0; i < size; i += PAGE_SIZE) { + paddr = paddr + i; + free_pfn_range(paddr, PAGE_SIZE); + } + } else { + /* free entire vma, page by page, using the pfn from pte */ + for (i = 0; i < vma_size; i += PAGE_SIZE) { + pte_t pte; + + if (follow_pfnmap_pte(vma, vma_start + i, &pte)) + continue; + + paddr = pte_pa(pte); + free_pfn_range(paddr, PAGE_SIZE); + } + } +} + #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_X86_PAT) /* get Nth element of the linked list */ -- cgit v1.2.3 From 2520bd3123c00272f818a176c92d03c7d0a113d6 Mon Sep 17 00:00:00 2001 From: "venkatesh.pallipadi@intel.com" Date: Thu, 18 Dec 2008 11:41:32 -0800 Subject: x86: PAT: add pgprot_writecombine() interface for drivers - v3 Impact: New mm functionality. Add pgprot_writecombine. pgprot_writecombine will be aliased to pgprot_noncached when not supported by the architecture. Signed-off-by: Venkatesh Pallipadi Signed-off-by: Suresh Siddha Signed-off-by: H. Peter Anvin --- arch/x86/mm/pat.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'arch/x86/mm/pat.c') diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c index 1069ffecf77..d5254bae84f 100644 --- a/arch/x86/mm/pat.c +++ b/arch/x86/mm/pat.c @@ -832,6 +832,14 @@ void untrack_pfn_vma(struct vm_area_struct *vma, unsigned long pfn, } } +pgprot_t pgprot_writecombine(pgprot_t prot) +{ + if (pat_enabled) + return __pgprot(pgprot_val(prot) | _PAGE_CACHE_WC); + else + return pgprot_noncached(prot); +} + #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_X86_PAT) /* get Nth element of the linked list */ -- cgit v1.2.3 From 982d789ab76c8a11426852fec2fdf2f412e21c0c Mon Sep 17 00:00:00 2001 From: "venkatesh.pallipadi@intel.com" Date: Fri, 19 Dec 2008 13:47:28 -0800 Subject: x86: PAT: remove follow_pfnmap_pte in favor of follow_phys Impact: Cleanup - removes a new function in favor of a recently modified older one. Replace follow_pfnmap_pte in pat code with follow_phys. follow_phys lso returns protection eliminating the need of pte_pgprot call. Using follow_phys also eliminates the need for pte_pa. Signed-off-by: Venkatesh Pallipadi Signed-off-by: Suresh Siddha Signed-off-by: H. Peter Anvin --- arch/x86/mm/pat.c | 30 +++++++++++------------------- 1 file changed, 11 insertions(+), 19 deletions(-) (limited to 'arch/x86/mm/pat.c') diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c index d5254bae84f..541bcc944a5 100644 --- a/arch/x86/mm/pat.c +++ b/arch/x86/mm/pat.c @@ -685,8 +685,7 @@ int track_pfn_vma_copy(struct vm_area_struct *vma) int retval = 0; unsigned long i, j; u64 paddr; - pgprot_t prot; - pte_t pte; + unsigned long prot; unsigned long vma_start = vma->vm_start; unsigned long vma_end = vma->vm_end; unsigned long vma_size = vma_end - vma_start; @@ -696,26 +695,22 @@ int track_pfn_vma_copy(struct vm_area_struct *vma) if (is_linear_pfn_mapping(vma)) { /* - * reserve the whole chunk starting from vm_pgoff, - * But, we have to get the protection from pte. + * reserve the whole chunk covered by vma. We need the + * starting address and protection from pte. */ - if (follow_pfnmap_pte(vma, vma_start, &pte)) { + if (follow_phys(vma, vma_start, 0, &prot, &paddr)) { WARN_ON_ONCE(1); - return -1; + return -EINVAL; } - prot = pte_pgprot(pte); - paddr = (u64)vma->vm_pgoff << PAGE_SHIFT; - return reserve_pfn_range(paddr, vma_size, prot); + return reserve_pfn_range(paddr, vma_size, __pgprot(prot)); } /* reserve entire vma page by page, using pfn and prot from pte */ for (i = 0; i < vma_size; i += PAGE_SIZE) { - if (follow_pfnmap_pte(vma, vma_start + i, &pte)) + if (follow_phys(vma, vma_start + i, 0, &prot, &paddr)) continue; - paddr = pte_pa(pte); - prot = pte_pgprot(pte); - retval = reserve_pfn_range(paddr, PAGE_SIZE, prot); + retval = reserve_pfn_range(paddr, PAGE_SIZE, __pgprot(prot)); if (retval) goto cleanup_ret; } @@ -724,10 +719,9 @@ int track_pfn_vma_copy(struct vm_area_struct *vma) cleanup_ret: /* Reserve error: Cleanup partial reservation and return error */ for (j = 0; j < i; j += PAGE_SIZE) { - if (follow_pfnmap_pte(vma, vma_start + j, &pte)) + if (follow_phys(vma, vma_start + j, 0, &prot, &paddr)) continue; - paddr = pte_pa(pte); free_pfn_range(paddr, PAGE_SIZE); } @@ -797,6 +791,7 @@ void untrack_pfn_vma(struct vm_area_struct *vma, unsigned long pfn, { unsigned long i; u64 paddr; + unsigned long prot; unsigned long vma_start = vma->vm_start; unsigned long vma_end = vma->vm_end; unsigned long vma_size = vma_end - vma_start; @@ -821,12 +816,9 @@ void untrack_pfn_vma(struct vm_area_struct *vma, unsigned long pfn, } else { /* free entire vma, page by page, using the pfn from pte */ for (i = 0; i < vma_size; i += PAGE_SIZE) { - pte_t pte; - - if (follow_pfnmap_pte(vma, vma_start + i, &pte)) + if (follow_phys(vma, vma_start + i, 0, &prot, &paddr)) continue; - paddr = pte_pa(pte); free_pfn_range(paddr, PAGE_SIZE); } } -- cgit v1.2.3 From c1c15b65ec30275575dac9322aae607075769fbc Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Tue, 23 Dec 2008 10:10:40 -0800 Subject: x86: PAT: fix address types in track_pfn_vma_new() Impact: cleanup, fix warning This warning: arch/x86/mm/pat.c: In function track_pfn_vma_copy: arch/x86/mm/pat.c:701: warning: passing argument 5 of follow_phys from incompatible pointer type Triggers because physical addresses are resource_size_t, not u64. This really matters when calling an interface like follow_phys() which takes a pointer to a physical address -- although on x86, being littleendian, it would generally work anyway as long as the memory region wasn't completely uninitialized. Signed-off-by: H. Peter Anvin Signed-off-by: Ingo Molnar --- arch/x86/mm/pat.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'arch/x86/mm/pat.c') diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c index 541bcc944a5..85cbd3cd372 100644 --- a/arch/x86/mm/pat.c +++ b/arch/x86/mm/pat.c @@ -684,7 +684,7 @@ int track_pfn_vma_copy(struct vm_area_struct *vma) { int retval = 0; unsigned long i, j; - u64 paddr; + resource_size_t paddr; unsigned long prot; unsigned long vma_start = vma->vm_start; unsigned long vma_end = vma->vm_end; @@ -746,8 +746,8 @@ int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t prot, { int retval = 0; unsigned long i, j; - u64 base_paddr; - u64 paddr; + resource_size_t base_paddr; + resource_size_t paddr; unsigned long vma_start = vma->vm_start; unsigned long vma_end = vma->vm_end; unsigned long vma_size = vma_end - vma_start; @@ -757,12 +757,12 @@ int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t prot, if (is_linear_pfn_mapping(vma)) { /* reserve the whole chunk starting from vm_pgoff */ - paddr = (u64)vma->vm_pgoff << PAGE_SHIFT; + paddr = (resource_size_t)vma->vm_pgoff << PAGE_SHIFT; return reserve_pfn_range(paddr, vma_size, prot); } /* reserve page by page using pfn and size */ - base_paddr = (u64)pfn << PAGE_SHIFT; + base_paddr = (resource_size_t)pfn << PAGE_SHIFT; for (i = 0; i < size; i += PAGE_SIZE) { paddr = base_paddr + i; retval = reserve_pfn_range(paddr, PAGE_SIZE, prot); @@ -790,7 +790,7 @@ void untrack_pfn_vma(struct vm_area_struct *vma, unsigned long pfn, unsigned long size) { unsigned long i; - u64 paddr; + resource_size_t paddr; unsigned long prot; unsigned long vma_start = vma->vm_start; unsigned long vma_end = vma->vm_end; @@ -801,14 +801,14 @@ void untrack_pfn_vma(struct vm_area_struct *vma, unsigned long pfn, if (is_linear_pfn_mapping(vma)) { /* free the whole chunk starting from vm_pgoff */ - paddr = (u64)vma->vm_pgoff << PAGE_SHIFT; + paddr = (resource_size_t)vma->vm_pgoff << PAGE_SHIFT; free_pfn_range(paddr, vma_size); return; } if (size != 0 && size != vma_size) { /* free page by page, using pfn and size */ - paddr = (u64)pfn << PAGE_SHIFT; + paddr = (resource_size_t)pfn << PAGE_SHIFT; for (i = 0; i < size; i += PAGE_SIZE) { paddr = paddr + i; free_pfn_range(paddr, PAGE_SIZE); -- cgit v1.2.3