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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/frv/mm/pgalloc.c | |
download | op-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip op-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/frv/mm/pgalloc.c')
-rw-r--r-- | arch/frv/mm/pgalloc.c | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/arch/frv/mm/pgalloc.c b/arch/frv/mm/pgalloc.c new file mode 100644 index 0000000..4eaec0f --- /dev/null +++ b/arch/frv/mm/pgalloc.c @@ -0,0 +1,159 @@ +/* pgalloc.c: page directory & page table allocation + * + * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/mm.h> +#include <linux/highmem.h> +#include <asm/pgalloc.h> +#include <asm/page.h> +#include <asm/cacheflush.h> + +pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((aligned(PAGE_SIZE))); +kmem_cache_t *pgd_cache; + +pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address) +{ + pte_t *pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT); + if (pte) + clear_page(pte); + return pte; +} + +struct page *pte_alloc_one(struct mm_struct *mm, unsigned long address) +{ + struct page *page; + +#ifdef CONFIG_HIGHPTE + page = alloc_pages(GFP_KERNEL|__GFP_HIGHMEM|__GFP_REPEAT, 0); +#else + page = alloc_pages(GFP_KERNEL|__GFP_REPEAT, 0); +#endif + if (page) + clear_highpage(page); + flush_dcache_page(page); + return page; +} + +void __set_pmd(pmd_t *pmdptr, unsigned long pmd) +{ + unsigned long *__ste_p = pmdptr->ste; + int loop; + + if (!pmd) { + memset(__ste_p, 0, PME_SIZE); + } + else { + BUG_ON(pmd & (0x3f00 | xAMPRx_SS | 0xe)); + + for (loop = PME_SIZE; loop > 0; loop -= 4) { + *__ste_p++ = pmd; + pmd += __frv_PT_SIZE; + } + } + + frv_dcache_writeback((unsigned long) pmdptr, (unsigned long) (pmdptr + 1)); +} + +/* + * List of all pgd's needed for non-PAE so it can invalidate entries + * in both cached and uncached pgd's; not needed for PAE since the + * kernel pmd is shared. If PAE were not to share the pmd a similar + * tactic would be needed. This is essentially codepath-based locking + * against pageattr.c; it is the unique case in which a valid change + * of kernel pagetables can't be lazily synchronized by vmalloc faults. + * vmalloc faults work because attached pagetables are never freed. + * If the locking proves to be non-performant, a ticketing scheme with + * checks at dup_mmap(), exec(), and other mmlist addition points + * could be used. The locking scheme was chosen on the basis of + * manfred's recommendations and having no core impact whatsoever. + * -- wli + */ +DEFINE_SPINLOCK(pgd_lock); +struct page *pgd_list; + +static inline void pgd_list_add(pgd_t *pgd) +{ + struct page *page = virt_to_page(pgd); + page->index = (unsigned long) pgd_list; + if (pgd_list) + pgd_list->private = (unsigned long) &page->index; + pgd_list = page; + page->private = (unsigned long) &pgd_list; +} + +static inline void pgd_list_del(pgd_t *pgd) +{ + struct page *next, **pprev, *page = virt_to_page(pgd); + next = (struct page *) page->index; + pprev = (struct page **) page->private; + *pprev = next; + if (next) + next->private = (unsigned long) pprev; +} + +void pgd_ctor(void *pgd, kmem_cache_t *cache, unsigned long unused) +{ + unsigned long flags; + + if (PTRS_PER_PMD == 1) + spin_lock_irqsave(&pgd_lock, flags); + + memcpy((pgd_t *) pgd + USER_PGDS_IN_LAST_PML4, + swapper_pg_dir + USER_PGDS_IN_LAST_PML4, + (PTRS_PER_PGD - USER_PGDS_IN_LAST_PML4) * sizeof(pgd_t)); + + if (PTRS_PER_PMD > 1) + return; + + pgd_list_add(pgd); + spin_unlock_irqrestore(&pgd_lock, flags); + memset(pgd, 0, USER_PGDS_IN_LAST_PML4 * sizeof(pgd_t)); +} + +/* never called when PTRS_PER_PMD > 1 */ +void pgd_dtor(void *pgd, kmem_cache_t *cache, unsigned long unused) +{ + unsigned long flags; /* can be called from interrupt context */ + + spin_lock_irqsave(&pgd_lock, flags); + pgd_list_del(pgd); + spin_unlock_irqrestore(&pgd_lock, flags); +} + +pgd_t *pgd_alloc(struct mm_struct *mm) +{ + pgd_t *pgd; + + pgd = kmem_cache_alloc(pgd_cache, GFP_KERNEL); + if (!pgd) + return pgd; + + return pgd; +} + +void pgd_free(pgd_t *pgd) +{ + /* in the non-PAE case, clear_page_tables() clears user pgd entries */ + kmem_cache_free(pgd_cache, pgd); +} + +void __init pgtable_cache_init(void) +{ + pgd_cache = kmem_cache_create("pgd", + PTRS_PER_PGD * sizeof(pgd_t), + PTRS_PER_PGD * sizeof(pgd_t), + 0, + pgd_ctor, + pgd_dtor); + if (!pgd_cache) + panic("pgtable_cache_init(): Cannot create pgd cache"); +} |