From: Paul Mundt Date: Tue, 24 Jul 2007 04:28:26 +0000 (+0900) Subject: sh: Add kmap_coherent()/kunmap_coherent() interface for SH-4. X-Git-Tag: v2.6.23-rc2~146^2~15 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8cf1a74305688c85fc8d23ab7432a0c447ee6413;p=linux-2.6 sh: Add kmap_coherent()/kunmap_coherent() interface for SH-4. This wires up kmap_coherent() and kunmap_coherent() on SH-4, and moves away from the p3map_mutex and reserved P3 space, opting to use fixmaps for colouring instead. The copy_user_page()/clear_user_page() implementations are moved to this, which fixes the nasty blowups with spinlock debugging as a result of having some of these calls nested under the page table lock. Signed-off-by: Paul Mundt --- diff --git a/arch/sh/mm/cache-sh4.c b/arch/sh/mm/cache-sh4.c index 981b040890..5d0f73a4fb 100644 --- a/arch/sh/mm/cache-sh4.c +++ b/arch/sh/mm/cache-sh4.c @@ -77,16 +77,8 @@ static void __init emit_cache_params(void) /* * SH-4 has virtually indexed and physically tagged cache. */ - -/* Worst case assumed to be 64k cache, direct-mapped i.e. 4 synonym bits. */ -#define MAX_P3_MUTEXES 16 - -struct mutex p3map_mutex[MAX_P3_MUTEXES]; - void __init p3_cache_init(void) { - int i; - compute_alias(¤t_cpu_data.icache); compute_alias(¤t_cpu_data.dcache); @@ -109,9 +101,6 @@ void __init p3_cache_init(void) if (ioremap_page_range(P3SEG, P3SEG + (PAGE_SIZE * 4), 0, PAGE_KERNEL)) panic("%s failed.", __FUNCTION__); - - for (i = 0; i < current_cpu_data.dcache.n_aliases; i++) - mutex_init(&p3map_mutex[i]); } /* diff --git a/arch/sh/mm/pg-sh4.c b/arch/sh/mm/pg-sh4.c index df69da9ca6..82b48e6a62 100644 --- a/arch/sh/mm/pg-sh4.c +++ b/arch/sh/mm/pg-sh4.c @@ -2,7 +2,7 @@ * arch/sh/mm/pg-sh4.c * * Copyright (C) 1999, 2000, 2002 Niibe Yutaka - * Copyright (C) 2002 - 2005 Paul Mundt + * Copyright (C) 2002 - 2007 Paul Mundt * * Released under the terms of the GNU GPL v2.0. */ @@ -11,10 +11,35 @@ #include #include -extern struct mutex p3map_mutex[]; - #define CACHE_ALIAS (current_cpu_data.dcache.alias_mask) +static inline void *kmap_coherent(struct page *page, unsigned long addr) +{ + enum fixed_addresses idx; + unsigned long vaddr, flags; + pte_t pte; + + inc_preempt_count(); + + idx = (addr & current_cpu_data.dcache.alias_mask) >> PAGE_SHIFT; + vaddr = __fix_to_virt(FIX_CMAP_END - idx); + pte = mk_pte(page, PAGE_KERNEL); + + local_irq_save(flags); + flush_tlb_one(get_asid(), vaddr); + local_irq_restore(flags); + + update_mmu_cache(NULL, vaddr, pte); + + return (void *)vaddr; +} + +static inline void kunmap_coherent(struct page *page) +{ + dec_preempt_count(); + preempt_check_resched(); +} + /* * clear_user_page * @to: P1 address @@ -27,25 +52,9 @@ void clear_user_page(void *to, unsigned long address, struct page *page) if (((address ^ (unsigned long)to) & CACHE_ALIAS) == 0) clear_page(to); else { - unsigned long phys_addr = PHYSADDR(to); - unsigned long p3_addr = P3SEG + (address & CACHE_ALIAS); - pgd_t *pgd = pgd_offset_k(p3_addr); - pud_t *pud = pud_offset(pgd, p3_addr); - pmd_t *pmd = pmd_offset(pud, p3_addr); - pte_t *pte = pte_offset_kernel(pmd, p3_addr); - pte_t entry; - unsigned long flags; - - entry = pfn_pte(phys_addr >> PAGE_SHIFT, PAGE_KERNEL); - mutex_lock(&p3map_mutex[(address & CACHE_ALIAS)>>12]); - set_pte(pte, entry); - local_irq_save(flags); - flush_tlb_one(get_asid(), p3_addr); - local_irq_restore(flags); - update_mmu_cache(NULL, p3_addr, entry); - __clear_user_page((void *)p3_addr, to); - pte_clear(&init_mm, p3_addr, pte); - mutex_unlock(&p3map_mutex[(address & CACHE_ALIAS)>>12]); + void *vto = kmap_coherent(page, address); + __clear_user_page(vto, to); + kunmap_coherent(vto); } } @@ -63,25 +72,9 @@ void copy_user_page(void *to, void *from, unsigned long address, if (((address ^ (unsigned long)to) & CACHE_ALIAS) == 0) copy_page(to, from); else { - unsigned long phys_addr = PHYSADDR(to); - unsigned long p3_addr = P3SEG + (address & CACHE_ALIAS); - pgd_t *pgd = pgd_offset_k(p3_addr); - pud_t *pud = pud_offset(pgd, p3_addr); - pmd_t *pmd = pmd_offset(pud, p3_addr); - pte_t *pte = pte_offset_kernel(pmd, p3_addr); - pte_t entry; - unsigned long flags; - - entry = pfn_pte(phys_addr >> PAGE_SHIFT, PAGE_KERNEL); - mutex_lock(&p3map_mutex[(address & CACHE_ALIAS)>>12]); - set_pte(pte, entry); - local_irq_save(flags); - flush_tlb_one(get_asid(), p3_addr); - local_irq_restore(flags); - update_mmu_cache(NULL, p3_addr, entry); - __copy_user_page((void *)p3_addr, from, to); - pte_clear(&init_mm, p3_addr, pte); - mutex_unlock(&p3map_mutex[(address & CACHE_ALIAS)>>12]); + void *vfrom = kmap_coherent(page, address); + __copy_user_page(vfrom, from, to); + kunmap_coherent(vfrom); } } diff --git a/include/asm-sh/fixmap.h b/include/asm-sh/fixmap.h index 458e9fa595..8a566177ad 100644 --- a/include/asm-sh/fixmap.h +++ b/include/asm-sh/fixmap.h @@ -46,6 +46,9 @@ * fix-mapped? */ enum fixed_addresses { +#define FIX_N_COLOURS 16 + FIX_CMAP_BEGIN, + FIX_CMAP_END = FIX_CMAP_BEGIN + FIX_N_COLOURS, #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, @@ -53,8 +56,8 @@ enum fixed_addresses { __end_of_fixed_addresses }; -extern void __set_fixmap (enum fixed_addresses idx, - unsigned long phys, pgprot_t flags); +extern void __set_fixmap(enum fixed_addresses idx, + unsigned long phys, pgprot_t flags); #define set_fixmap(idx, phys) \ __set_fixmap(idx, phys, PAGE_KERNEL) @@ -106,5 +109,4 @@ static inline unsigned long virt_to_fix(const unsigned long vaddr) BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START); return __virt_to_fix(vaddr); } - #endif