diff options
Diffstat (limited to 'arch/ia64/kernel/efi.c')
-rw-r--r-- | arch/ia64/kernel/efi.c | 156 |
1 files changed, 102 insertions, 54 deletions
diff --git a/arch/ia64/kernel/efi.c b/arch/ia64/kernel/efi.c index 12cfedce73b1..c33d0ba7e300 100644 --- a/arch/ia64/kernel/efi.c +++ b/arch/ia64/kernel/efi.c @@ -8,6 +8,8 @@ * Copyright (C) 1999-2003 Hewlett-Packard Co. * David Mosberger-Tang <davidm@hpl.hp.com> * Stephane Eranian <eranian@hpl.hp.com> + * (c) Copyright 2006 Hewlett-Packard Development Company, L.P. + * Bjorn Helgaas <bjorn.helgaas@hp.com> * * All EFI Runtime Services are not implemented yet as EFI only * supports physical mode addressing on SoftSDV. This is to be fixed @@ -622,28 +624,20 @@ efi_get_iobase (void) return 0; } -static efi_memory_desc_t * -efi_memory_descriptor (unsigned long phys_addr) +static struct kern_memdesc * +kern_memory_descriptor (unsigned long phys_addr) { - void *efi_map_start, *efi_map_end, *p; - efi_memory_desc_t *md; - u64 efi_desc_size; - - efi_map_start = __va(ia64_boot_param->efi_memmap); - efi_map_end = efi_map_start + ia64_boot_param->efi_memmap_size; - efi_desc_size = ia64_boot_param->efi_memdesc_size; + struct kern_memdesc *md; - for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) { - md = p; - - if (phys_addr - md->phys_addr < (md->num_pages << EFI_PAGE_SHIFT)) + for (md = kern_memmap; md->start != ~0UL; md++) { + if (phys_addr - md->start < (md->num_pages << EFI_PAGE_SHIFT)) return md; } return 0; } -static int -efi_memmap_has_mmio (void) +static efi_memory_desc_t * +efi_memory_descriptor (unsigned long phys_addr) { void *efi_map_start, *efi_map_end, *p; efi_memory_desc_t *md; @@ -656,8 +650,8 @@ efi_memmap_has_mmio (void) for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) { md = p; - if (md->type == EFI_MEMORY_MAPPED_IO) - return 1; + if (phys_addr - md->phys_addr < (md->num_pages << EFI_PAGE_SHIFT)) + return md; } return 0; } @@ -683,71 +677,125 @@ efi_mem_attributes (unsigned long phys_addr) } EXPORT_SYMBOL(efi_mem_attributes); -/* - * Determines whether the memory at phys_addr supports the desired - * attribute (WB, UC, etc). If this returns 1, the caller can safely - * access size bytes at phys_addr with the specified attribute. - */ -int -efi_mem_attribute_range (unsigned long phys_addr, unsigned long size, u64 attr) +u64 +efi_mem_attribute (unsigned long phys_addr, unsigned long size) { unsigned long end = phys_addr + size; efi_memory_desc_t *md = efi_memory_descriptor(phys_addr); + u64 attr; + + if (!md) + return 0; + + /* + * EFI_MEMORY_RUNTIME is not a memory attribute; it just tells + * the kernel that firmware needs this region mapped. + */ + attr = md->attribute & ~EFI_MEMORY_RUNTIME; + do { + unsigned long md_end = efi_md_end(md); + + if (end <= md_end) + return attr; + + md = efi_memory_descriptor(md_end); + if (!md || (md->attribute & ~EFI_MEMORY_RUNTIME) != attr) + return 0; + } while (md); + return 0; +} + +u64 +kern_mem_attribute (unsigned long phys_addr, unsigned long size) +{ + unsigned long end = phys_addr + size; + struct kern_memdesc *md; + u64 attr; /* - * Some firmware doesn't report MMIO regions in the EFI memory - * map. The Intel BigSur (a.k.a. HP i2000) has this problem. - * On those platforms, we have to assume UC is valid everywhere. + * This is a hack for ioremap calls before we set up kern_memmap. + * Maybe we should do efi_memmap_init() earlier instead. */ - if (!md || (md->attribute & attr) != attr) { - if (attr == EFI_MEMORY_UC && !efi_memmap_has_mmio()) - return 1; + if (!kern_memmap) { + attr = efi_mem_attribute(phys_addr, size); + if (attr & EFI_MEMORY_WB) + return EFI_MEMORY_WB; return 0; } + md = kern_memory_descriptor(phys_addr); + if (!md) + return 0; + + attr = md->attribute; do { - unsigned long md_end = efi_md_end(md); + unsigned long md_end = kmd_end(md); if (end <= md_end) - return 1; + return attr; - md = efi_memory_descriptor(md_end); - if (!md || (md->attribute & attr) != attr) + md = kern_memory_descriptor(md_end); + if (!md || md->attribute != attr) return 0; } while (md); return 0; } +EXPORT_SYMBOL(kern_mem_attribute); -/* - * For /dev/mem, we only allow read & write system calls to access - * write-back memory, because read & write don't allow the user to - * control access size. - */ int valid_phys_addr_range (unsigned long phys_addr, unsigned long size) { - return efi_mem_attribute_range(phys_addr, size, EFI_MEMORY_WB); + u64 attr; + + /* + * /dev/mem reads and writes use copy_to_user(), which implicitly + * uses a granule-sized kernel identity mapping. It's really + * only safe to do this for regions in kern_memmap. For more + * details, see Documentation/ia64/aliasing.txt. + */ + attr = kern_mem_attribute(phys_addr, size); + if (attr & EFI_MEMORY_WB || attr & EFI_MEMORY_UC) + return 1; + return 0; } -/* - * We allow mmap of anything in the EFI memory map that supports - * either write-back or uncacheable access. For uncacheable regions, - * the supported access sizes are system-dependent, and the user is - * responsible for using the correct size. - * - * Note that this doesn't currently allow access to hot-added memory, - * because that doesn't appear in the boot-time EFI memory map. - */ int valid_mmap_phys_addr_range (unsigned long phys_addr, unsigned long size) { - if (efi_mem_attribute_range(phys_addr, size, EFI_MEMORY_WB)) - return 1; + /* + * MMIO regions are often missing from the EFI memory map. + * We must allow mmap of them for programs like X, so we + * currently can't do any useful validation. + */ + return 1; +} - if (efi_mem_attribute_range(phys_addr, size, EFI_MEMORY_UC)) - return 1; +pgprot_t +phys_mem_access_prot(struct file *file, unsigned long pfn, unsigned long size, + pgprot_t vma_prot) +{ + unsigned long phys_addr = pfn << PAGE_SHIFT; + u64 attr; - return 0; + /* + * For /dev/mem mmap, we use user mappings, but if the region is + * in kern_memmap (and hence may be covered by a kernel mapping), + * we must use the same attribute as the kernel mapping. + */ + attr = kern_mem_attribute(phys_addr, size); + if (attr & EFI_MEMORY_WB) + return pgprot_cacheable(vma_prot); + else if (attr & EFI_MEMORY_UC) + return pgprot_noncached(vma_prot); + + /* + * Some chipsets don't support UC access to memory. If + * WB is supported, we prefer that. + */ + if (efi_mem_attribute(phys_addr, size) & EFI_MEMORY_WB) + return pgprot_cacheable(vma_prot); + + return pgprot_noncached(vma_prot); } int __init |