[patch RFC 13/15] mm/highmem: Remove the old kmap_atomic cruft

Thomas Gleixner
2020-09-19T09:50:35Z

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
include/linux/highmem.h | 65 ++----------------------------------------------
mm/highmem.c | 28 +++++++++++++++++---
2 files changed, 28 insertions(+), 65 deletions(-)

--- a/include/linux/highmem.h
+++ b/include/linux/highmem.h
@@ -94,27 +94,6 @@ static inline void kunmap(struct page *p
* be used in IRQ contexts, so in some (very limited) cases we need
* it.
*/
-
-#ifndef CONFIG_KMAP_ATOMIC_GENERIC
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot);
-void kunmap_atomic_high(void *kvaddr);
-
-static inline void *kmap_atomic_prot(struct page *page, pgprot_t prot)
-{
- preempt_disable();
- pagefault_disable();
- if (!PageHighMem(page))
- return page_address(page);
- return kmap_atomic_high_prot(page, prot);
-}
-
-static inline void __kunmap_atomic(void *vaddr)
-{
- kunmap_atomic_high(vaddr);
- pagefault_enable();
-}
-#else /* !CONFIG_KMAP_ATOMIC_GENERIC */
-
static inline void *kmap_atomic_prot(struct page *page, pgprot_t prot)
{
preempt_disable();
@@ -127,17 +106,14 @@ static inline void *kmap_atomic_pfn(unsi
return kmap_atomic_pfn_prot(pfn, kmap_prot);
}

-static inline void __kunmap_atomic(void *addr)
+static inline void *kmap_atomic(struct page *page)
{
- kumap_atomic_indexed(addr);
+ return kmap_atomic_prot(page, kmap_prot);
}

-
-#endif /* CONFIG_KMAP_ATOMIC_GENERIC */
-
-static inline void *kmap_atomic(struct page *page)
+static inline void __kunmap_atomic(void *addr)
{
- return kmap_atomic_prot(page, kmap_prot);
+ kumap_atomic_indexed(addr);
}

/* declarations for linux/mm/highmem.c */
@@ -233,39 +209,6 @@ static inline void __kunmap_atomic(void

#endif /* CONFIG_HIGHMEM */

-#if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
-
-DECLARE_PER_CPU(int, __kmap_atomic_idx);
-
-static inline int kmap_atomic_idx_push(void)
-{
- int idx = __this_cpu_inc_return(__kmap_atomic_idx) - 1;
-
-#ifdef CONFIG_DEBUG_HIGHMEM
- WARN_ON_ONCE(in_irq() && !irqs_disabled());
- BUG_ON(idx >= KM_TYPE_NR);
-#endif
- return idx;
-}
-
-static inline int kmap_atomic_idx(void)
-{
- return __this_cpu_read(__kmap_atomic_idx) - 1;
-}
-
-static inline void kmap_atomic_idx_pop(void)
-{
-#ifdef CONFIG_DEBUG_HIGHMEM
- int idx = __this_cpu_dec_return(__kmap_atomic_idx);
-
- BUG_ON(idx < 0);
-#else
- __this_cpu_dec(__kmap_atomic_idx);
-#endif
-}
-
-#endif
-
/*
* 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.
--- a/mm/highmem.c
+++ b/mm/highmem.c
@@ -31,10 +31,6 @@
#include <asm/tlbflush.h>
#include <linux/vmalloc.h>

-#if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
-DEFINE_PER_CPU(int, __kmap_atomic_idx);
-#endif
-
/*
* Virtual_count is not a pure "count".
* 0 means that it is not mapped, and has not been mapped
@@ -380,6 +376,30 @@ static inline void kmap_high_unmap_tempo
#endif /* CONFIG_HIGHMEM */

#ifdef CONFIG_KMAP_ATOMIC_GENERIC
+
+static DEFINE_PER_CPU(int, __kmap_atomic_idx);
+
+static inline int kmap_atomic_idx_push(void)
+{
+ int idx = __this_cpu_inc_return(__kmap_atomic_idx) - 1;
+
+ WARN_ON_ONCE(in_irq() && !irqs_disabled());
+ BUG_ON(idx >= KM_TYPE_NR);
+ return idx;
+}
+
+static inline int kmap_atomic_idx(void)
+{
+ return __this_cpu_read(__kmap_atomic_idx) - 1;
+}
+
+static inline void kmap_atomic_idx_pop(void)
+{
+ int idx = __this_cpu_dec_return(__kmap_atomic_idx);
+
+ BUG_ON(idx < 0);
+}
+
#ifndef arch_kmap_temp_post_map
# define arch_kmap_temp_post_map(vaddr, pteval) do { } while (0)
#endif