diff options
Diffstat (limited to 'include/linux/io-mapping.h')
| -rw-r--r-- | include/linux/io-mapping.h | 168 |
1 files changed, 114 insertions, 54 deletions
diff --git a/include/linux/io-mapping.h b/include/linux/io-mapping.h index 657fab4efab3..c16353cc6e3c 100644 --- a/include/linux/io-mapping.h +++ b/include/linux/io-mapping.h @@ -1,18 +1,6 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ /* * 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 @@ -21,26 +9,28 @@ #include <linux/types.h> #include <linux/slab.h> #include <linux/bug.h> -#include <asm/io.h> +#include <linux/io.h> +#include <linux/pgtable.h> #include <asm/page.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 + * See Documentation/driver-api/io-mapping.rst */ -#ifdef CONFIG_HAVE_ATOMIC_IOMAP - -#include <asm/iomap.h> - struct io_mapping { resource_size_t base; unsigned long size; pgprot_t prot; + void __iomem *iomem; }; +#ifdef CONFIG_HAVE_ATOMIC_IOMAP + +#include <linux/pfn.h> +#include <asm/iomap.h> /* * For small address space machines, mapping large objects * into the kernel virtual space isn't practical. Where @@ -49,34 +39,25 @@ struct io_mapping { */ static inline struct io_mapping * -io_mapping_create_wc(resource_size_t base, unsigned long size) +io_mapping_init_wc(struct io_mapping *iomap, + resource_size_t base, + unsigned long size) { - struct io_mapping *iomap; pgprot_t prot; - iomap = kmalloc(sizeof(*iomap), GFP_KERNEL); - if (!iomap) - goto out_err; - if (iomap_create_wc(base, size, &prot)) - goto out_free; + return NULL; iomap->base = base; iomap->size = size; iomap->prot = prot; return iomap; - -out_free: - kfree(iomap); -out_err: - return NULL; } static inline void -io_mapping_free(struct io_mapping *mapping) +io_mapping_fini(struct io_mapping *mapping) { iomap_free(mapping->base, mapping->size); - kfree(mapping); } /* Atomic map/unmap */ @@ -85,29 +66,54 @@ io_mapping_map_atomic_wc(struct io_mapping *mapping, unsigned long offset) { resource_size_t phys_addr; - unsigned long pfn; BUG_ON(offset >= mapping->size); phys_addr = mapping->base + offset; - pfn = (unsigned long) (phys_addr >> PAGE_SHIFT); - return iomap_atomic_prot_pfn(pfn, mapping->prot); + if (!IS_ENABLED(CONFIG_PREEMPT_RT)) + preempt_disable(); + else + migrate_disable(); + pagefault_disable(); + return __iomap_local_pfn_prot(PHYS_PFN(phys_addr), mapping->prot); } static inline void io_mapping_unmap_atomic(void __iomem *vaddr) { - iounmap_atomic(vaddr); + kunmap_local_indexed((void __force *)vaddr); + pagefault_enable(); + if (!IS_ENABLED(CONFIG_PREEMPT_RT)) + preempt_enable(); + else + migrate_enable(); +} + +static inline void __iomem * +io_mapping_map_local_wc(struct io_mapping *mapping, unsigned long offset) +{ + resource_size_t phys_addr; + + BUG_ON(offset >= mapping->size); + phys_addr = mapping->base + offset; + return __iomap_local_pfn_prot(PHYS_PFN(phys_addr), mapping->prot); +} + +static inline void io_mapping_unmap_local(void __iomem *vaddr) +{ + kunmap_local_indexed((void __force *)vaddr); } static inline void __iomem * -io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset) +io_mapping_map_wc(struct io_mapping *mapping, + unsigned long offset, + unsigned long size) { resource_size_t phys_addr; BUG_ON(offset >= mapping->size); phys_addr = mapping->base + offset; - return ioremap_wc(phys_addr, PAGE_SIZE); + return ioremap_wc(phys_addr, size); } static inline void @@ -116,24 +122,45 @@ io_mapping_unmap(void __iomem *vaddr) iounmap(vaddr); } -#else +#else /* HAVE_ATOMIC_IOMAP */ #include <linux/uaccess.h> -/* this struct isn't actually defined anywhere */ -struct io_mapping; - /* Create the io_mapping object*/ static inline struct io_mapping * -io_mapping_create_wc(resource_size_t base, unsigned long size) +io_mapping_init_wc(struct io_mapping *iomap, + resource_size_t base, + unsigned long size) +{ + iomap->iomem = ioremap_wc(base, size); + if (!iomap->iomem) + return NULL; + + iomap->base = base; + iomap->size = size; + iomap->prot = pgprot_writecombine(PAGE_KERNEL); + + return iomap; +} + +static inline void +io_mapping_fini(struct io_mapping *mapping) +{ + iounmap(mapping->iomem); +} + +/* Non-atomic map/unmap */ +static inline void __iomem * +io_mapping_map_wc(struct io_mapping *mapping, + unsigned long offset, + unsigned long size) { - return (struct io_mapping __force *) ioremap_wc(base, size); + return mapping->iomem + offset; } static inline void -io_mapping_free(struct io_mapping *mapping) +io_mapping_unmap(void __iomem *vaddr) { - iounmap((void __force __iomem *) mapping); } /* Atomic map/unmap */ @@ -141,28 +168,61 @@ static inline void __iomem * io_mapping_map_atomic_wc(struct io_mapping *mapping, unsigned long offset) { + if (!IS_ENABLED(CONFIG_PREEMPT_RT)) + preempt_disable(); + else + migrate_disable(); pagefault_disable(); - return ((char __force __iomem *) mapping) + offset; + return io_mapping_map_wc(mapping, offset, PAGE_SIZE); } static inline void io_mapping_unmap_atomic(void __iomem *vaddr) { + io_mapping_unmap(vaddr); pagefault_enable(); + if (!IS_ENABLED(CONFIG_PREEMPT_RT)) + preempt_enable(); + else + migrate_enable(); } -/* Non-atomic map/unmap */ static inline void __iomem * -io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset) +io_mapping_map_local_wc(struct io_mapping *mapping, unsigned long offset) { - return ((char __force __iomem *) mapping) + offset; + return io_mapping_map_wc(mapping, offset, PAGE_SIZE); } -static inline void -io_mapping_unmap(void __iomem *vaddr) +static inline void io_mapping_unmap_local(void __iomem *vaddr) { + io_mapping_unmap(vaddr); } -#endif /* HAVE_ATOMIC_IOMAP */ +#endif /* !HAVE_ATOMIC_IOMAP */ + +static inline struct io_mapping * +io_mapping_create_wc(resource_size_t base, + unsigned long size) +{ + struct io_mapping *iomap; + + iomap = kmalloc(sizeof(*iomap), GFP_KERNEL); + if (!iomap) + return NULL; + + if (!io_mapping_init_wc(iomap, base, size)) { + kfree(iomap); + return NULL; + } + + return iomap; +} + +static inline void +io_mapping_free(struct io_mapping *iomap) +{ + io_mapping_fini(iomap); + kfree(iomap); +} #endif /* _LINUX_IO_MAPPING_H */ |