mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-12 13:55:32 +00:00
![Thomas Gleixner](/assets/img/avatar_default.png)
Move the gory details of kmap & al into a private header and only document the interfaces which are usable by drivers. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linuxfoundation.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://lore.kernel.org/r/20201103095858.827582066@linutronix.de
174 lines
3.6 KiB
C
174 lines
3.6 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _LINUX_HIGHMEM_INTERNAL_H
|
|
#define _LINUX_HIGHMEM_INTERNAL_H
|
|
|
|
/*
|
|
* Outside of CONFIG_HIGHMEM to support X86 32bit iomap_atomic() cruft.
|
|
*/
|
|
#ifdef CONFIG_KMAP_LOCAL
|
|
void *__kmap_local_pfn_prot(unsigned long pfn, pgprot_t prot);
|
|
void *__kmap_local_page_prot(struct page *page, pgprot_t prot);
|
|
void kunmap_local_indexed(void *vaddr);
|
|
#endif
|
|
|
|
#ifdef CONFIG_HIGHMEM
|
|
#include <asm/highmem.h>
|
|
|
|
#ifndef ARCH_HAS_KMAP_FLUSH_TLB
|
|
static inline void kmap_flush_tlb(unsigned long addr) { }
|
|
#endif
|
|
|
|
#ifndef kmap_prot
|
|
#define kmap_prot PAGE_KERNEL
|
|
#endif
|
|
|
|
void *kmap_high(struct page *page);
|
|
void kunmap_high(struct page *page);
|
|
void __kmap_flush_unused(void);
|
|
struct page *__kmap_to_page(void *addr);
|
|
|
|
static inline void *kmap(struct page *page)
|
|
{
|
|
void *addr;
|
|
|
|
might_sleep();
|
|
if (!PageHighMem(page))
|
|
addr = page_address(page);
|
|
else
|
|
addr = kmap_high(page);
|
|
kmap_flush_tlb((unsigned long)addr);
|
|
return addr;
|
|
}
|
|
|
|
static inline void kunmap(struct page *page)
|
|
{
|
|
might_sleep();
|
|
if (!PageHighMem(page))
|
|
return;
|
|
kunmap_high(page);
|
|
}
|
|
|
|
static inline struct page *kmap_to_page(void *addr)
|
|
{
|
|
return __kmap_to_page(addr);
|
|
}
|
|
|
|
static inline void kmap_flush_unused(void)
|
|
{
|
|
__kmap_flush_unused();
|
|
}
|
|
|
|
static inline void *kmap_atomic_prot(struct page *page, pgprot_t prot)
|
|
{
|
|
preempt_disable();
|
|
pagefault_disable();
|
|
return __kmap_local_page_prot(page, prot);
|
|
}
|
|
|
|
static inline void *kmap_atomic(struct page *page)
|
|
{
|
|
return kmap_atomic_prot(page, kmap_prot);
|
|
}
|
|
|
|
static inline void *kmap_atomic_pfn(unsigned long pfn)
|
|
{
|
|
preempt_disable();
|
|
pagefault_disable();
|
|
return __kmap_local_pfn_prot(pfn, kmap_prot);
|
|
}
|
|
|
|
static inline void __kunmap_atomic(void *addr)
|
|
{
|
|
kunmap_local_indexed(addr);
|
|
pagefault_enable();
|
|
preempt_enable();
|
|
}
|
|
|
|
unsigned int __nr_free_highpages(void);
|
|
extern atomic_long_t _totalhigh_pages;
|
|
|
|
static inline unsigned int nr_free_highpages(void)
|
|
{
|
|
return __nr_free_highpages();
|
|
}
|
|
|
|
static inline unsigned long totalhigh_pages(void)
|
|
{
|
|
return (unsigned long)atomic_long_read(&_totalhigh_pages);
|
|
}
|
|
|
|
static inline void totalhigh_pages_inc(void)
|
|
{
|
|
atomic_long_inc(&_totalhigh_pages);
|
|
}
|
|
|
|
static inline void totalhigh_pages_add(long count)
|
|
{
|
|
atomic_long_add(count, &_totalhigh_pages);
|
|
}
|
|
|
|
#else /* CONFIG_HIGHMEM */
|
|
|
|
static inline struct page *kmap_to_page(void *addr)
|
|
{
|
|
return virt_to_page(addr);
|
|
}
|
|
|
|
static inline void *kmap(struct page *page)
|
|
{
|
|
might_sleep();
|
|
return page_address(page);
|
|
}
|
|
|
|
static inline void kunmap_high(struct page *page) { }
|
|
static inline void kmap_flush_unused(void) { }
|
|
|
|
static inline void kunmap(struct page *page)
|
|
{
|
|
#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
|
|
kunmap_flush_on_unmap(page_address(page));
|
|
#endif
|
|
}
|
|
|
|
static inline void *kmap_atomic(struct page *page)
|
|
{
|
|
preempt_disable();
|
|
pagefault_disable();
|
|
return page_address(page);
|
|
}
|
|
|
|
static inline void *kmap_atomic_prot(struct page *page, pgprot_t prot)
|
|
{
|
|
return kmap_atomic(page);
|
|
}
|
|
|
|
static inline void *kmap_atomic_pfn(unsigned long pfn)
|
|
{
|
|
return kmap_atomic(pfn_to_page(pfn));
|
|
}
|
|
|
|
static inline void __kunmap_atomic(void *addr)
|
|
{
|
|
#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
|
|
kunmap_flush_on_unmap(addr);
|
|
#endif
|
|
pagefault_enable();
|
|
preempt_enable();
|
|
}
|
|
|
|
static inline unsigned int nr_free_highpages(void) { return 0; }
|
|
static inline unsigned long totalhigh_pages(void) { return 0UL; }
|
|
|
|
#endif /* CONFIG_HIGHMEM */
|
|
|
|
/*
|
|
* Prevent people trying to call kunmap_atomic() as if it were kunmap()
|
|
* kunmap_atomic() should get the return value of kmap_atomic, not the page.
|
|
*/
|
|
#define kunmap_atomic(__addr) \
|
|
do { \
|
|
BUILD_BUG_ON(__same_type((__addr), struct page *)); \
|
|
__kunmap_atomic(__addr); \
|
|
} while (0)
|
|
|
|
#endif
|