diff options
| -rw-r--r-- | Documentation/io-mapping.txt | 82 | ||||
| -rw-r--r-- | arch/x86/Kconfig | 4 | ||||
| -rw-r--r-- | arch/x86/include/asm/fixmap.h | 4 | ||||
| -rw-r--r-- | arch/x86/include/asm/fixmap_32.h | 4 | ||||
| -rw-r--r-- | arch/x86/include/asm/highmem.h | 5 | ||||
| -rw-r--r-- | arch/x86/mm/Makefile | 2 | ||||
| -rw-r--r-- | arch/x86/mm/init_32.c | 3 | ||||
| -rw-r--r-- | arch/x86/mm/iomap_32.c | 59 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/i915_drv.h | 3 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/i915_gem.c | 174 | ||||
| -rw-r--r-- | include/asm-x86/iomap.h | 30 | ||||
| -rw-r--r-- | include/linux/io-mapping.h | 125 |
12 files changed, 390 insertions, 105 deletions
diff --git a/Documentation/io-mapping.txt b/Documentation/io-mapping.txt new file mode 100644 index 00000000000..473e43b2d58 --- /dev/null +++ b/Documentation/io-mapping.txt @@ -0,0 +1,82 @@ +The io_mapping functions in linux/io-mapping.h provide an abstraction for +efficiently mapping small regions of an I/O device to the CPU. The initial +usage is to support the large graphics aperture on 32-bit processors where +ioremap_wc cannot be used to statically map the entire aperture to the CPU +as it would consume too much of the kernel address space. + +A mapping object is created during driver initialization using + + struct io_mapping *io_mapping_create_wc(unsigned long base, + unsigned long size) + + 'base' is the bus address of the region to be made + mappable, while 'size' indicates how large a mapping region to + enable. Both are in bytes. + + This _wc variant provides a mapping which may only be used + with the io_mapping_map_atomic_wc or io_mapping_map_wc. + +With this mapping object, individual pages can be mapped either atomically +or not, depending on the necessary scheduling environment. Of course, atomic +maps are more efficient: + + void *io_mapping_map_atomic_wc(struct io_mapping *mapping, + unsigned long offset) + + 'offset' is the offset within the defined mapping region. + Accessing addresses beyond the region specified in the + creation function yields undefined results. Using an offset + which is not page aligned yields an undefined result. The + return value points to a single page in CPU address space. + + This _wc variant returns a write-combining map to the + page and may only be used with mappings created by + io_mapping_create_wc + + Note that the task may not sleep while holding this page + mapped. + + void io_mapping_unmap_atomic(void *vaddr) + + 'vaddr' must be the the value returned by the last + io_mapping_map_atomic_wc call. This unmaps the specified + page and allows the task to sleep once again. + +If you need to sleep while holding the lock, you can use the non-atomic +variant, although they may be significantly slower. + + void *io_mapping_map_wc(struct io_mapping *mapping, + unsigned long offset) + + This works like io_mapping_map_atomic_wc except it allows + the task to sleep while holding the page mapped. + + void io_mapping_unmap(void *vaddr) + + This works like io_mapping_unmap_atomic, except it is used + for pages mapped with io_mapping_map_wc. + +At driver close time, the io_mapping object must be freed: + + void io_mapping_free(struct io_mapping *mapping) + +Current Implementation: + +The initial implementation of these functions uses existing mapping +mechanisms and so provides only an abstraction layer and no new +functionality. + +On 64-bit processors, io_mapping_create_wc calls ioremap_wc for the whole +range, creating a permanent kernel-visible mapping to the resource. The +map_atomic and map functions add the requested offset to the base of the +virtual address returned by ioremap_wc. + +On 32-bit processors with HIGHMEM defined, io_mapping_map_atomic_wc uses +kmap_atomic_pfn to map the specified page in an atomic fashion; +kmap_atomic_pfn isn't really supposed to be used with device pages, but it +provides an efficient mapping for this usage. + +On 32-bit processors without HIGHMEM defined, io_mapping_map_atomic_wc and +io_mapping_map_wc both use ioremap_wc, a terribly inefficient function which +performs an IPI to inform all processors about the new mapping. This results +in a significant performance penalty. diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 6f20718d315..e60c59b81bd 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1894,6 +1894,10 @@ config SYSVIPC_COMPAT endmenu +config HAVE_ATOMIC_IOMAP + def_bool y + depends on X86_32 + source "net/Kconfig" source "drivers/Kconfig" diff --git a/arch/x86/include/asm/fixmap.h b/arch/x86/include/asm/fixmap.h index 8668a94f850..23696d44a0a 100644 --- a/arch/x86/include/asm/fixmap.h +++ b/arch/x86/include/asm/fixmap.h @@ -9,6 +9,10 @@ extern int fixmaps_set; +extern pte_t *kmap_pte; +extern pgprot_t kmap_prot; +extern pte_t *pkmap_page_table; + void __native_set_fixmap(enum fixed_addresses idx, pte_t pte); void native_set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t flags); diff --git a/arch/x86/include/asm/fixmap_32.h b/arch/x86/include/asm/fixmap_32.h index 09f29ab5c13..c7115c1d721 100644 --- a/arch/x86/include/asm/fixmap_32.h +++ b/arch/x86/include/asm/fixmap_32.h @@ -28,10 +28,8 @@ extern unsigned long __FIXADDR_TOP; #include <asm/acpi.h> #include <asm/apicdef.h> #include <asm/page.h> -#ifdef CONFIG_HIGHMEM #include <linux/threads.h> #include <asm/kmap_types.h> -#endif /* * Here we define all the compile-time 'special' virtual @@ -75,10 +73,8 @@ enum fixed_addresses { #ifdef CONFIG_X86_CYCLONE_TIMER FIX_CYCLONE_TIMER, /*cyclone timer register*/ #endif -#ifdef CONFIG_HIGHMEM FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */ FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1, -#endif #ifdef CONFIG_PCI_MMCONFIG FIX_PCIE_MCFG, #endif diff --git a/arch/x86/include/asm/highmem.h b/arch/x86/include/asm/highmem.h index a3b3b7c3027..bf9276bea66 100644 --- a/arch/x86/include/asm/highmem.h +++ b/arch/x86/include/asm/highmem.h @@ -25,14 +25,11 @@ #include <asm/kmap_types.h> #include <asm/tlbflush.h> #include <asm/paravirt.h> +#include <asm/fixmap.h> /* declarations for highmem.c */ extern unsigned long highstart_pfn, highend_pfn; -extern pte_t *kmap_pte; -extern pgprot_t kmap_prot; -extern pte_t *pkmap_page_table; - /* * Right now we initialize only a single pte table. It can be extended * easily, subsequent pte tables have to be allocated in one physical diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile index 59f89b434b4..fea4565ff57 100644 --- a/arch/x86/mm/Makefile +++ b/arch/x86/mm/Makefile @@ -1,7 +1,7 @@ obj-y := init_$(BITS).o fault.o ioremap.o extable.o pageattr.o mmap.o \ pat.o pgtable.o gup.o -obj-$(CONFIG_X86_32) += pgtable_32.o +obj-$(CONFIG_X86_32) += pgtable_32.o iomap_32.o obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o obj-$(CONFIG_X86_PTDUMP) += dump_pagetables.o diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index 8396868e82c..c483f424207 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -334,7 +334,6 @@ int devmem_is_allowed(unsigned long pagenr) return 0; } -#ifdef CONFIG_HIGHMEM pte_t *kmap_pte; pgprot_t kmap_prot; @@ -357,6 +356,7 @@ static void __init kmap_init(void) kmap_prot = PAGE_KERNEL; } +#ifdef CONFIG_HIGHMEM static void __init permanent_kmaps_init(pgd_t *pgd_base) { unsigned long vaddr; @@ -436,7 +436,6 @@ static void __init set_highmem_pages_init(void) #endif /* !CONFIG_NUMA */ #else -# define kmap_init() do { } while (0) # define permanent_kmaps_init(pgd_base) do { } while (0) # define set_highmem_pages_init() do { } while (0) #endif /* CONFIG_HIGHMEM */ diff --git a/arch/x86/mm/iomap_32.c b/arch/x86/mm/iomap_32.c new file mode 100644 index 00000000000..d0151d8ce45 --- /dev/null +++ b/arch/x86/mm/iomap_32.c @@ -0,0 +1,59 @@ +/* + * Copyright © 2008 Ingo Molnar + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + */ + +#include <asm/iomap.h> +#include <linux/module.h> + +/* Map 'pfn' using fixed map 'type' and protections 'prot' + */ +void * +iomap_atomic_prot_pfn(unsigned long pfn, enum km_type type, pgprot_t prot) +{ + enum fixed_addresses idx; + unsigned long vaddr; + + pagefault_disable(); + + idx = type + KM_TYPE_NR*smp_processor_id(); + vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); + set_pte(kmap_pte-idx, pfn_pte(pfn, prot)); + arch_flush_lazy_mmu_mode(); + + return (void*) vaddr; +} +EXPORT_SYMBOL_GPL(iomap_atomic_prot_pfn); + +void +iounmap_atomic(void *kvaddr, enum km_type type) +{ + unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK; + enum fixed_addresses idx = type + KM_TYPE_NR*smp_processor_id(); + + /* + * Force other mappings to Oops if they'll try to access this pte + * without first remap it. Keeping stale mappings around is a bad idea + * also, in case the page changes cacheability attributes or becomes + * a protected page in a hypervisor. + */ + if (vaddr == __fix_to_virt(FIX_KMAP_BEGIN+idx)) + kpte_clear_flush(kmap_pte-idx, vaddr); + + arch_flush_lazy_mmu_mode(); + pagefault_enable(); +} +EXPORT_SYMBOL_GPL(iounmap_atomic); diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index cc8a9f3f7a6..572dcd0e3e0 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -31,6 +31,7 @@ #define _I915_DRV_H_ #include "i915_reg.h" +#include <linux/io-mapping.h> /* General customization: */ @@ -246,6 +247,8 @@ typedef struct drm_i915_private { struct { struct drm_mm gtt_space; + struct io_mapping *gtt_mapping; + /** * List of objects currently involved in rendering from the * ringbuffer. diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index c1733ac4a7f..b0ec73fa6a9 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -193,35 +193,50 @@ i915_gem_pread_ioctl(struct drm_device *dev, void *data, return 0; } -/* - * Try to write quickly with an atomic kmap. Return true on success. - * - * If this fails (which includes a partial write), we'll redo the whole - * thing with the slow version. - * - * This is a workaround for the low performance of iounmap (approximate - * 10% cpu cost on normal 3D workloads). kmap_atomic on HIGHMEM kernels - * happens to let us map card memory without taking IPIs. When the vmap - * rework lands we should be able to dump this hack. +/* This is the fast write path which cannot handle + * page faults in the source data */ -static inline int fast_user_write(unsigned long pfn, char __user *user_data, - int l, int o) + +static inline int +fast_user_write(struct io_mapping *mapping, + loff_t page_base, int page_offset, + char __user *user_data, + int length) { -#ifdef CONFIG_HIGHMEM - unsigned long unwritten; char *vaddr_atomic; + unsigned long unwritten; - vaddr_atomic = kmap_atomic_pfn(pfn, KM_USER0); -#if WATCH_PWRITE - DRM_INFO("pwrite i %d o %d l %d pfn %ld vaddr %p\n", - i, o, l, pfn, vaddr_atomic); -#endif - unwritten = __copy_from_user_inatomic_nocache(vaddr_atomic + o, user_data, l); - kunmap_atomic(vaddr_atomic, KM_USER0); - return !unwritten; -#else + vaddr_atomic = io_mapping_map_atomic_wc(mapping, page_base); + unwritten = __copy_from_user_inatomic_nocache(vaddr_atomic + page_offset, + user_data, length); + io_mapping_unmap_atomic(vaddr_atomic); + if (unwritten) + return -EFAULT; + return 0; +} + +/* Here's the write path which can sleep for + * page faults + */ + +static inline int +slow_user_write(struct io_mapping *mapping, + loff_t page_base, int page_offset, + char __user *user_data, + int length) +{ + char __iomem *vaddr; + unsigned long unwritten; + + vaddr = io_mapping_map_wc(mapping, page_base); + if (vaddr == NULL) + return -EFAULT; + unwritten = __copy_from_user(vaddr + page_offset, + user_data, length); + io_mapping_unmap(vaddr); + if (unwritten) + return -EFAULT; return 0; -#endif } static int @@ -230,10 +245,12 @@ i915_gem_gtt_pwrite(struct drm_device *dev, struct drm_gem_object *obj, struct drm_file *file_priv) { struct drm_i915_gem_object *obj_priv = obj->driver_private; + drm_i915_private_t *dev_priv = dev->dev_private; ssize_t remain; - loff_t offset; + loff_t offset, page_base; char __user *user_data; - int ret = 0; + int page_offset, page_length; + int ret; user_data = (char __user *) (uintptr_t) args->data_ptr; remain = args->size; @@ -257,57 +274,37 @@ i915_gem_gtt_pwrite(struct drm_device *dev, struct drm_gem_object *obj, obj_priv->dirty = 1; while (remain > 0) { - unsigned long pfn; - int i, o, l; - /* Operation in this page * - * i = page number - * o = offset within page - * l = bytes to copy + * page_base = page offset within aperture + * page_offset = offset within page + * page_length = bytes to copy for this page */ - i = offset >> PAGE_SHIFT; - o = offset & (PAGE_SIZE-1); - l = remain; - if ((o + l) > PAGE_SIZE) - l = PAGE_SIZE - o; - - pfn = (dev->agp->base >> PAGE_SHIFT) + i; - - if (!fast_user_write(pfn, user_data, l, o)) { - unsigned long unwritten; - char __iomem *vaddr; - - vaddr = ioremap_wc(pfn << PAGE_SHIFT, PAGE_SIZE); -#if WATCH_PWRITE - DRM_INFO("pwrite slow i %d o %d l %d " - "pfn %ld vaddr %p\n", - i, o, l, pfn, vaddr); -#endif - if (vaddr == NULL) { - ret = -EFAULT; - goto fail; - } - unwritten = __copy_from_user(vaddr + o, user_data, l); -#if WATCH_PWRITE - DRM_INFO("unwritten %ld\n", unwritten); -#endif - iounmap(vaddr); - if (unwritten) { - ret = -EFAULT; + page_base = (offset & ~(PAGE_SIZE-1)); + page_offset = offset & (PAGE_SIZE-1); + page_length = remain; + if ((page_offset + remain) > PAGE_SIZE) + page_length = PAGE_SIZE - page_offset; + + ret = fast_user_write (dev_priv->mm.gtt_mapping, page_base, + page_offset, user_data, page_length); + + /* If we get a fault while copying data, then (presumably) our + * source page isn't available. In this case, use the + * non-atomic function + */ + if (ret) { + ret = slow_user_write (dev_priv->mm.gtt_mapping, + page_base, page_offset, + user_data, page_length); + if (ret) goto fail; - } } - remain -= l; - user_data += l; - offset += l; + remain -= page_length; + user_data += page_length; + offset += page_length; } -#if WATCH_PWRITE && 1 - i915_gem_clflush_object(obj); - i915_gem_dump_object(obj, args->offset + args->size, __func__, ~0); - i915_gem_clflush_object(obj); -#endif fail: i915_gem_object_unpin(obj); @@ -1525,12 +1522,12 @@ i915_gem_object_pin_and_relocate(struct drm_gem_object *obj, struct drm_i915_gem_exec_object *entry) { struct drm_device *dev = obj->dev; + drm_i915_private_t *dev_priv = dev->dev_private; struct drm_i915_gem_relocation_entry reloc; struct drm_i915_gem_relocation_entry __user *relocs; struct drm_i915_gem_object *obj_priv = obj->driver_private; int i, ret; - uint32_t last_reloc_offset = -1; - void __iomem *reloc_page = NULL; + void __iomem *reloc_page; /* Choose the GTT offset for our buffer and put it there. */ ret = i915_gem_object_pin(obj, (uint32_t) entry->alignment); @@ -1653,26 +1650,11 @@ i915_gem_object_pin_and_relocate(struct drm_gem_object *obj, * perform. */ reloc_offset = obj_priv->gtt_offset + reloc.offset; - if (reloc_page == NULL || - (last_reloc_offset & ~(PAGE_SIZE - 1)) != - (reloc_offset & ~(PAGE_SIZE - 1))) { - if (reloc_page != NULL) - iounmap(reloc_page); - - reloc_page = ioremap_wc(dev->agp->base + - (reloc_offset & - ~(PAGE_SIZE - 1)), - PAGE_SIZE); - last_reloc_offset = reloc_offset; - if (reloc_page == NULL) { - drm_gem_object_unreference(target_obj); - i915_gem_object_unpin(obj); - return -ENOMEM; - } - } - + reloc_page = io_mapping_map_atomic_wc(dev_priv->mm.gtt_mapping, + (reloc_offset & + ~(PAGE_SIZE - 1))); reloc_entry = (uint32_t __iomem *)(reloc_page + - (reloc_offset & (PAGE_SIZE - 1))); + (reloc_offset & (PAGE_SIZE - 1))); reloc_val = target_obj_priv->gtt_offset + reloc.delta; #if WATCH_BUF @@ -1681,6 +1663,7 @@ i915_gem_object_pin_and_relocate(struct drm_gem_object *obj, readl(reloc_entry), reloc_val); #endif writel(reloc_val, reloc_entry); + io_mapping_unmap_atomic(reloc_page); /* Write the updated presumed offset for this entry back out * to the user. @@ -1696,9 +1679,6 @@ i915_gem_object_pin_and_relocate(struct drm_gem_object *obj, drm_gem_object_unreference(target_obj); } - if (reloc_page != NULL) - iounmap(reloc_page); - #if WATCH_BUF if (0) i915_gem_dump_object(obj, 128, __func__, ~0); @@ -2540,6 +2520,10 @@ i915_gem_entervt_ioctl(struct drm_device *dev, void *data, if (ret != 0) return ret; + dev_priv->mm.gtt_mapping = io_mapping_create_wc(dev->agp->base, + dev->agp->agp_info.aper_size + * 1024 * 1024); + mutex_lock(&dev->struct_mutex); BUG_ON(!list_empty(&dev_priv->mm.active_list)); BUG_ON(!list_empty(&dev_priv->mm.flushing_list)); @@ -2557,11 +2541,13 @@ int i915_gem_leavevt_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) { + drm_i915_private_t *dev_priv = dev->dev_private; int ret; ret = i915_gem_idle(dev); drm_irq_uninstall(dev); + io_mapping_free(dev_priv->mm.gtt_mapping); return ret; } diff --git a/include/asm-x86/iomap.h b/include/asm-x86/iomap.h new file mode 100644 index 00000000000..c1f06289b14 --- /dev/null +++ b/include/asm-x86/iomap.h @@ -0,0 +1,30 @@ +/* + * Copyright © 2008 Ingo Molnar + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + */ + +#include <linux/fs.h> +#include <linux/mm.h> +#include <linux/uaccess.h> +#include <asm/cacheflush.h> +#include <asm/pgtable.h> +#include <asm/tlbflush.h> + +void * +iomap_atomic_prot_pfn(unsigned long pfn, enum km_type type, pgprot_t prot); + +void +iounmap_atomic(void *kvaddr, enum km_type type); diff --git a/include/linux/io-mapping.h b/include/linux/io-mapping.h new file mode 100644 index 00000000000..82df31726a5 --- /dev/null +++ b/include/linux/io-mapping.h @@ -0,0 +1,125 @@ +/* + * Copyright © 2008 Keith Packard <keithp@keithp.com> + * + * This file is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. + */ + +#ifndef _LINUX_IO_MAPPING_H +#define _LINUX_IO_MAPPING_H + +#include <linux/types.h> +#include <asm/io.h> +#include <asm/page.h> +#include <asm/iomap.h> + +/* + * The io_mapping mechanism provides an abstraction for mapping + * individual pages from an io device to the CPU in an efficient fashion. + * + * See Documentation/io_mapping.txt + */ + +/* this struct isn't actually defined anywhere */ +struct io_mapping; + +#ifdef CONFIG_HAVE_ATOMIC_IOMAP + +/* + * For small address space machines, mapping large objects + * into the kernel virtual space isn't practical. Where + * available, use fixmap support to dynamically map pages + * of the object at run time. + */ + +static inline struct io_mapping * +io_mapping_create_wc(unsigned long base, unsigned long size) +{ + return (struct io_mapping *) base; +} + +static inline void +io_mapping_free(struct io_mapping *mapping) +{ +} + +/* Atomic map/unmap */ +static inline void * +io_mapping_map_atomic_wc(struct io_mapping *mapping, unsigned long offset) +{ + offset += (unsigned long) mapping; + return iomap_atomic_prot_pfn(offset >> PAGE_SHIFT, KM_USER0, + __pgprot(__PAGE_KERNEL_WC)); +} + +static inline void +io_mapping_unmap_atomic(void *vaddr) +{ + iounmap_atomic(vaddr, KM_USER0); +} + +static inline void * +io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset) +{ + offset += (unsigned long) mapping; + return ioremap_wc(offset, PAGE_SIZE); +} + +static inline void +io_mapping_unmap(void *vaddr) +{ + iounmap(vaddr); +} + +#else + +/* Create the io_mapping object*/ +static inline struct io_mapping * +io_mapping_create_wc(unsigned long base, unsigned long size) +{ + return (struct io_mapping *) ioremap_wc(base, size); +} + +static inline void +io_mapping_free(struct io_mapping *mapping) +{ + iounmap(mapping); +} + +/* Atomic map/unmap */ +static inline void * +io_mapping_map_atomic_wc(struct io_mapping *mapping, unsigned long offset) +{ + return ((char *) mapping) + offset; +} + +static inline void +io_mapping_unmap_atomic(void *vaddr) +{ +} + +/* Non-atomic map/unmap */ +static inline void * +io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset) +{ + return ((char *) mapping) + offset; +} + +static inline void +io_mapping_unmap(void *vaddr) +{ +} + +#endif /* HAVE_ATOMIC_IOMAP */ + +#endif /* _LINUX_IO_MAPPING_H */ |