From 4ad0ae8c64ac8f81a3651bca11be7c3cb086df80 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Thu, 29 Apr 2021 22:59:01 -0700 Subject: mm/vmalloc: remove unmap_kernel_range MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This is a shim around vunmap_range, get rid of it. Move the main API comment from the _noflush variant to the normal variant, and make _noflush internal to mm/. [npiggin@gmail.com: fix nommu builds and a comment bug per sfr] Link: https://lkml.kernel.org/r/1617292598.m6g0knx24s.astroid@bobo.none [akpm@linux-foundation.org: move vunmap_range_noflush() stub inside !CONFIG_MMU, not !CONFIG_NUMA] [npiggin@gmail.com: fix nommu builds] Link: https://lkml.kernel.org/r/1617292497.o1uhq5ipxp.astroid@bobo.none Link: https://lkml.kernel.org/r/20210322021806.892164-5-npiggin@gmail.com Signed-off-by: Nicholas Piggin Reviewed-by: Christoph Hellwig Cc: Cédric Le Goater Cc: Uladzislau Rezki Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/vmalloc.c | 59 ++++++++++++++++++++++++++++------------------------------- 1 file changed, 28 insertions(+), 31 deletions(-) (limited to 'mm/vmalloc.c') diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 527781a3a0fe..f7a53c19e84b 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -378,22 +378,20 @@ static void vunmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end, } while (p4d++, addr = next, addr != end); } -/** - * unmap_kernel_range_noflush - unmap kernel VM area - * @start: start of the VM area to unmap - * @size: size of the VM area to unmap +/* + * vunmap_range_noflush is similar to vunmap_range, but does not + * flush caches or TLBs. * - * Unmap PFN_UP(@size) pages at @addr. The VM area @addr and @size specify - * should have been allocated using get_vm_area() and its friends. + * The caller is responsible for calling flush_cache_vmap() before calling + * this function, and flush_tlb_kernel_range after it has returned + * successfully (and before the addresses are expected to cause a page fault + * or be re-mapped for something else, if TLB flushes are being delayed or + * coalesced). * - * NOTE: - * This function does NOT do any cache flushing. The caller is responsible - * for calling flush_cache_vunmap() on to-be-mapped areas before calling this - * function and flush_tlb_kernel_range() after. + * This is an internal function only. Do not use outside mm/. */ -void unmap_kernel_range_noflush(unsigned long start, unsigned long size) +void vunmap_range_noflush(unsigned long start, unsigned long end) { - unsigned long end = start + size; unsigned long next; pgd_t *pgd; unsigned long addr = start; @@ -414,6 +412,22 @@ void unmap_kernel_range_noflush(unsigned long start, unsigned long size) arch_sync_kernel_mappings(start, end); } +/** + * vunmap_range - unmap kernel virtual addresses + * @addr: start of the VM area to unmap + * @end: end of the VM area to unmap (non-inclusive) + * + * Clears any present PTEs in the virtual address range, flushes TLBs and + * caches. Any subsequent access to the address before it has been re-mapped + * is a kernel bug. + */ +void vunmap_range(unsigned long addr, unsigned long end) +{ + flush_cache_vunmap(addr, end); + vunmap_range_noflush(addr, end); + flush_tlb_kernel_range(addr, end); +} + static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, pgprot_t prot, struct page **pages, int *nr, pgtbl_mod_mask *mask) @@ -1712,7 +1726,7 @@ static void free_vmap_area_noflush(struct vmap_area *va) static void free_unmap_vmap_area(struct vmap_area *va) { flush_cache_vunmap(va->va_start, va->va_end); - unmap_kernel_range_noflush(va->va_start, va->va_end - va->va_start); + vunmap_range_noflush(va->va_start, va->va_end); if (debug_pagealloc_enabled_static()) flush_tlb_kernel_range(va->va_start, va->va_end); @@ -1990,7 +2004,7 @@ static void vb_free(unsigned long addr, unsigned long size) offset = (addr & (VMAP_BLOCK_SIZE - 1)) >> PAGE_SHIFT; vb = xa_load(&vmap_blocks, addr_to_vb_idx(addr)); - unmap_kernel_range_noflush(addr, size); + vunmap_range_noflush(addr, addr + size); if (debug_pagealloc_enabled_static()) flush_tlb_kernel_range(addr, addr + size); @@ -2307,23 +2321,6 @@ void __init vmalloc_init(void) vmap_initialized = true; } -/** - * unmap_kernel_range - unmap kernel VM area and flush cache and TLB - * @addr: start of the VM area to unmap - * @size: size of the VM area to unmap - * - * Similar to unmap_kernel_range_noflush() but flushes vcache before - * the unmapping and tlb after. - */ -void unmap_kernel_range(unsigned long addr, unsigned long size) -{ - unsigned long end = addr + size; - - flush_cache_vunmap(addr, end); - unmap_kernel_range_noflush(addr, size); - flush_tlb_kernel_range(addr, end); -} - static inline void setup_vmalloc_vm_locked(struct vm_struct *vm, struct vmap_area *va, unsigned long flags, const void *caller) { -- cgit v1.2.3