From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Wilson Subject: [PATCH 2/4] io-mapping: Always create a struct to hold metadata about the io-mapping Date: Sat, 21 Jun 2014 16:53:54 +0100 Message-ID: <1403366036-10169-2-git-send-email-chris@chris-wilson.co.uk> References: <20140619135944.20837E00A3@blue.fi.intel.com> <1403366036-10169-1-git-send-email-chris@chris-wilson.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1403366036-10169-1-git-send-email-chris@chris-wilson.co.uk> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: intel-gfx@lists.freedesktop.org Cc: linux-mm@kvack.org List-Id: linux-mm.kvack.org Currently, we only allocate a structure to hold metadata if we need to allocate an ioremap for every access, such as on x86-32. However, it would be useful to store basic information about the io-mapping, such as its page protection, on all platforms. Signed-off-by: Chris Wilson Cc: linux-mm@kvack.org --- include/linux/io-mapping.h | 52 ++++++++++++++++++++++++++++------------------ 1 file changed, 32 insertions(+), 20 deletions(-) diff --git a/include/linux/io-mapping.h b/include/linux/io-mapping.h index 657fab4efab3..e053011f50bb 100644 --- a/include/linux/io-mapping.h +++ b/include/linux/io-mapping.h @@ -31,16 +31,17 @@ * See Documentation/io-mapping.txt */ -#ifdef CONFIG_HAVE_ATOMIC_IOMAP - -#include - struct io_mapping { resource_size_t base; unsigned long size; pgprot_t prot; + void __iomem *iomem; }; + +#ifdef CONFIG_HAVE_ATOMIC_IOMAP + +#include /* * For small address space machines, mapping large objects * into the kernel virtual space isn't practical. Where @@ -119,48 +120,59 @@ io_mapping_unmap(void __iomem *vaddr) #else #include - -/* this struct isn't actually defined anywhere */ -struct io_mapping; +#include /* Create the io_mapping object*/ static inline struct io_mapping * io_mapping_create_wc(resource_size_t base, unsigned long size) { - return (struct io_mapping __force *) ioremap_wc(base, size); + struct io_mapping *iomap; + + iomap = kmalloc(sizeof(*iomap), GFP_KERNEL); + if (!iomap) + return NULL; + + iomap->base = base; + iomap->size = size; + iomap->iomem = ioremap_wc(base, size); + iomap->prot = pgprot_writecombine(PAGE_KERNEL_IO); + + return iomap; } static inline void io_mapping_free(struct io_mapping *mapping) { - iounmap((void __force __iomem *) mapping); + iounmap(mapping->iomem); + kfree(mapping); } -/* Atomic map/unmap */ +/* Non-atomic map/unmap */ static inline void __iomem * -io_mapping_map_atomic_wc(struct io_mapping *mapping, - unsigned long offset) +io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset) { - pagefault_disable(); - return ((char __force __iomem *) mapping) + offset; + return mapping->iomem + offset; } static inline void -io_mapping_unmap_atomic(void __iomem *vaddr) +io_mapping_unmap(void __iomem *vaddr) { - pagefault_enable(); } -/* Non-atomic map/unmap */ +/* Atomic map/unmap */ static inline void __iomem * -io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset) +io_mapping_map_atomic_wc(struct io_mapping *mapping, + unsigned long offset) { - return ((char __force __iomem *) mapping) + offset; + pagefault_disable(); + return io_mapping_map_wc(mapping, offset); } static inline void -io_mapping_unmap(void __iomem *vaddr) +io_mapping_unmap_atomic(void __iomem *vaddr) { + io_mapping_unmap(vaddr); + pagefault_enable(); } #endif /* HAVE_ATOMIC_IOMAP */ -- 2.0.0