diff options
| -rw-r--r-- | mm/percpu-vm.c | 451 | ||||
| -rw-r--r-- | mm/percpu.c | 452 |
2 files changed, 475 insertions, 428 deletions
diff --git a/mm/percpu-vm.c b/mm/percpu-vm.c new file mode 100644 index 000000000000..7d9c1d0ebd3f --- /dev/null +++ b/mm/percpu-vm.c @@ -0,0 +1,451 @@ +/* + * mm/percpu-vm.c - vmalloc area based chunk allocation + * + * Copyright (C) 2010 SUSE Linux Products GmbH + * Copyright (C) 2010 Tejun Heo <tj@kernel.org> + * + * This file is released under the GPLv2. + * + * Chunks are mapped into vmalloc areas and populated page by page. + * This is the default chunk allocator. + */ + +static struct page *pcpu_chunk_page(struct pcpu_chunk *chunk, + unsigned int cpu, int page_idx) +{ + /* must not be used on pre-mapped chunk */ + WARN_ON(chunk->immutable); + + return vmalloc_to_page((void *)pcpu_chunk_addr(chunk, cpu, page_idx)); +} + +/** + * pcpu_get_pages_and_bitmap - get temp pages array and bitmap + * @chunk: chunk of interest + * @bitmapp: output parameter for bitmap + * @may_alloc: may allocate the array + * + * Returns pointer to array of pointers to struct page and bitmap, + * both of which can be indexed with pcpu_page_idx(). The returned + * array is cleared to zero and *@bitmapp is copied from + * @chunk->populated. Note that there is only one array and bitmap + * and access exclusion is the caller's responsibility. + * + * CONTEXT: + * pcpu_alloc_mutex and does GFP_KERNEL allocation if @may_alloc. + * Otherwise, don't care. + * + * RETURNS: + * Pointer to temp pages array on success, NULL on failure. + */ +static struct page **pcpu_get_pages_and_bitmap(struct pcpu_chunk *chunk, + unsigned long **bitmapp, + bool may_alloc) +{ + static struct page **pages; + static unsigned long *bitmap; + size_t pages_size = pcpu_nr_units * pcpu_unit_pages * sizeof(pages[0]); + size_t bitmap_size = BITS_TO_LONGS(pcpu_unit_pages) * + sizeof(unsigned long); + + if (!pages || !bitmap) { + if (may_alloc && !pages) + pages = pcpu_mem_alloc(pages_size); + if (may_alloc && !bitmap) + bitmap = pcpu_mem_alloc(bitmap_size); + if (!pages || !bitmap) + return NULL; + } + + memset(pages, 0, pages_size); + bitmap_copy(bitmap, chunk->populated, pcpu_unit_pages); + + *bitmapp = bitmap; + return pages; +} + +/** + * pcpu_free_pages - free pages which were allocated for @chunk + * @chunk: chunk pages were allocated for + * @pages: array of pages to be freed, indexed by pcpu_page_idx() + * @populated: populated bitmap + * @page_start: page index of the first page to be freed + * @page_end: page index of the last page to be freed + 1 + * + * Free pages [@page_start and @page_end) in @pages for all units. + * The pages were allocated for @chunk. + */ +static void pcpu_free_pages(struct pcpu_chunk *chunk, + struct page **pages, unsigned long *populated, + int page_start, int page_end) +{ + unsigned int cpu; + int i; + + for_each_possible_cpu(cpu) { + for (i = page_start; i < page_end; i++) { + struct page *page = pages[pcpu_page_idx(cpu, i)]; + + if (page) + __free_page(page); + } + } +} + +/** + * pcpu_alloc_pages - allocates pages for @chunk + * @chunk: target chunk + * @pages: array to put the allocated pages into, indexed by pcpu_page_idx() + * @populated: populated bitmap + * @page_start: page index of the first page to be allocated + * @page_end: page index of the last page to be allocated + 1 + * + * Allocate pages [@page_start,@page_end) into @pages for all units. + * The allocation is for @chunk. Percpu core doesn't care about the + * content of @pages and will pass it verbatim to pcpu_map_pages(). + */ +static int pcpu_alloc_pages(struct pcpu_chunk *chunk, + struct page **pages, unsigned long *populated, + int page_start, int page_end) +{ + const gfp_t gfp = GFP_KERNEL | __GFP_HIGHMEM | __GFP_COLD; + unsigned int cpu; + int i; + + for_each_possible_cpu(cpu) { + for (i = page_start; i < page_end; i++) { + struct page **pagep = &pages[pcpu_page_idx(cpu, i)]; + + *pagep = alloc_pages_node(cpu_to_node(cpu), gfp, 0); + if (!*pagep) { + pcpu_free_pages(chunk, pages, populated, + page_start, page_end); + return -ENOMEM; + } + } + } + return 0; +} + +/** + * pcpu_pre_unmap_flush - flush cache prior to unmapping + * @chunk: chunk the regions to be flushed belongs to + * @page_start: page index of the first page to be flushed + * @page_end: page index of the last page to be flushed + 1 + * + * Pages in [@page_start,@page_end) of @chunk are about to be + * unmapped. Flush cache. As each flushing trial can be very + * expensive, issue flush on the whole region at once rather than + * doing it for each cpu. This could be an overkill but is more + * scalable. + */ +static void pcpu_pre_unmap_flush(struct pcpu_chunk *chunk, + int page_start, int page_end) +{ + flush_cache_vunmap( + pcpu_chunk_addr(chunk, pcpu_first_unit_cpu, page_start), + pcpu_chunk_addr(chunk, pcpu_last_unit_cpu, page_end)); +} + +static void __pcpu_unmap_pages(unsigned long addr, int nr_pages) +{ + unmap_kernel_range_noflush(addr, nr_pages << PAGE_SHIFT); +} + +/** + * pcpu_unmap_pages - unmap pages out of a pcpu_chunk + * @chunk: chunk of interest + * @pages: pages array which can be used to pass information to free + * @populated: populated bitmap + * @page_start: page index of the first page to unmap + * @page_end: page index of the last page to unmap + 1 + * + * For each cpu, unmap pages [@page_start,@page_end) out of @chunk. + * Corresponding elements in @pages were cleared by the caller and can + * be used to carry information to pcpu_free_pages() which will be + * called after all unmaps are finished. The caller should call + * proper pre/post flush functions. + */ +static void pcpu_unmap_pages(struct pcpu_chunk *chunk, + struct page **pages, unsigned long *populated, + int page_start, int page_end) +{ + unsigned int cpu; + int i; + + for_each_possible_cpu(cpu) { + for (i = page_start; i < page_end; i++) { + struct page *page; + + page = pcpu_chunk_page(chunk, cpu, i); + WARN_ON(!page); + pages[pcpu_page_idx(cpu, i)] = page; + } + __pcpu_unmap_pages(pcpu_chunk_addr(chunk, cpu, page_start), + page_end - page_start); + } + + for (i = page_start; i < page_end; i++) + __clear_bit(i, populated); +} + +/** + * pcpu_post_unmap_tlb_flush - flush TLB after unmapping + * @chunk: pcpu_chunk the regions to be flushed belong to + * @page_start: page index of the first page to be flushed + * @page_end: page index of the last page to be flushed + 1 + * + * Pages [@page_start,@page_end) of @chunk have been unmapped. Flush + * TLB for the regions. This can be skipped if the area is to be + * returned to vmalloc as vmalloc will handle TLB flushing lazily. + * + * As with pcpu_pre_unmap_flush(), TLB flushing also is done at once + * for the whole region. + */ +static void pcpu_post_unmap_tlb_flush(struct pcpu_chunk *chunk, + int page_start, int page_end) +{ + flush_tlb_kernel_range( + pcpu_chunk_addr(chunk, pcpu_first_unit_cpu, page_start), + pcpu_chunk_addr(chunk, pcpu_last_unit_cpu, page_end)); +} + +static int __pcpu_map_pages(unsigned long addr, struct page **pages, + int nr_pages) +{ + return map_kernel_range_noflush(addr, nr_pages << PAGE_SHIFT, + PAGE_KERNEL, pages); +} + +/** + * pcpu_map_pages - map pages into a pcpu_chunk + * @chunk: chunk of interest + * @pages: pages array containing pages to be mapped + * @populated: populated bitmap + * @page_start: page index of the first page to map + * @page_end: page index of the last page to map + 1 + * + * For each cpu, map pages [@page_start,@page_end) into @chunk. The + * caller is responsible for calling pcpu_post_map_flush() after all + * mappings are complete. + * + * This function is responsible for setting corresponding bits in + * @chunk->populated bitmap and whatever is necessary for reverse + * lookup (addr -> chunk). + */ +static int pcpu_map_pages(struct pcpu_chunk *chunk, + struct page **pages, unsigned long *populated, + int page_start, int page_end) +{ + unsigned int cpu, tcpu; + int i, err; + + for_each_possible_cpu(cpu) { + err = __pcpu_map_pages(pcpu_chunk_addr(chunk, cpu, page_start), + &pages[pcpu_page_idx(cpu, page_start)], + page_end - page_start); + if (err < 0) + goto err; + } + + /* mapping successful, link chunk and mark populated */ + for (i = page_start; i < page_end; i++) { + for_each_possible_cpu(cpu) + pcpu_set_page_chunk(pages[pcpu_page_idx(cpu, i)], + chunk); + __set_bit(i, populated); + } + + return 0; + +err: + for_each_possible_cpu(tcpu) { + if (tcpu == cpu) + break; + __pcpu_unmap_pages(pcpu_chunk_addr(chunk, tcpu, page_start), + page_end - page_start); + } + return err; +} + +/** + * pcpu_post_map_flush - flush cache after mapping + * @chunk: pcpu_chunk the regions to be flushed belong to + * @page_start: page index of the first page to be flushed + * @page_end: page index of the last page to be flushed + 1 + * + * Pages [@page_start,@page_end) of @chunk have been mapped. Flush + * cache. + * + * As with pcpu_pre_unmap_flush(), TLB flushing also is done at once + * for the whole region. + */ +static void pcpu_post_map_flush(struct pcpu_chunk *chunk, + int page_start, int page_end) +{ + flush_cache_vmap( + pcpu_chunk_addr(chunk, pcpu_first_unit_cpu, page_start), + pcpu_chunk_addr(chunk, pcpu_last_unit_cpu, page_end)); +} + +/** + * pcpu_populate_chunk - populate and map an area of a pcpu_chunk + * @chunk: chunk of interest + * @off: offset to the area to populate + * @size: size of the area to populate in bytes + * + * For each cpu, populate and map pages [@page_start,@page_end) into + * @chunk. The area is cleared on return. + * + * CONTEXT: + * pcpu_alloc_mutex, does GFP_KERNEL allocation. + */ +static int pcpu_populate_chunk(struct pcpu_chunk *chunk, int off, int size) +{ + int page_start = PFN_DOWN(off); + int page_end = PFN_UP(off + size); + int free_end = page_start, unmap_end = page_start; + struct page **pages; + unsigned long *populated; + unsigned int cpu; + int rs, re, rc; + + /* quick path, check whether all pages are already there */ + rs = page_start; + pcpu_next_pop(chunk, &rs, &re, page_end); + if (rs == page_start && re == page_end) + goto clear; + + /* need to allocate and map pages, this chunk can't be immutable */ + WARN_ON(chunk->immutable); + + pages = pcpu_get_pages_and_bitmap(chunk, &populated, true); + if (!pages) + return -ENOMEM; + + /* alloc and map */ + pcpu_for_each_unpop_region(chunk, rs, re, page_start, page_end) { + rc = pcpu_alloc_pages(chunk, pages, populated, rs, re); + if (rc) + goto err_free; + free_end = re; + } + + pcpu_for_each_unpop_region(chunk, rs, re, page_start, page_end) { + rc = pcpu_map_pages(chunk, pages, populated, rs, re); + if (rc) + goto err_unmap; + unmap_end = re; + } + pcpu_post_map_flush(chunk, page_start, page_end); + + /* commit new bitmap */ + bitmap_copy(chunk->populated, populated, pcpu_unit_pages); +clear: + for_each_possible_cpu(cpu) + memset((void *)pcpu_chunk_addr(chunk, cpu, 0) + off, 0, size); + return 0; + +err_unmap: + pcpu_pre_unmap_flush(chunk, page_start, unmap_end); + pcpu_for_each_unpop_region(chunk, rs, re, page_start, unmap_end) + pcpu_unmap_pages(chunk, pages, populated, rs, re); + pcpu_post_unmap_tlb_flush(chunk, page_start, unmap_end); +err_free: + pcpu_for_each_unpop_region(chunk, rs, re, page_start, free_end) + pcpu_free_pages(chunk, pages, populated, rs, re); + return rc; +} + +/** + * pcpu_depopulate_chunk - depopulate and unmap an area of a pcpu_chunk + * @chunk: chunk to depopulate + * @off: offset to the area to depopulate + * @size: size of the area to depopulate in bytes + * @flush: whether to flush cache and tlb or not + * + * For each cpu, depopulate and unmap pages [@page_start,@page_end) + * from @chunk. If @flush is true, vcache is flushed before unmapping + * and tlb after. + * + * CONTEXT: + * pcpu_alloc_mutex. + */ +static void pcpu_depopulate_chunk(struct pcpu_chunk *chunk, int off, int size) +{ + int page_start = PFN_DOWN(off); + int page_end = PFN_UP(off + size); + struct page **pages; + unsigned long *populated; + int rs, re; + + /* quick path, check whether it's empty already */ + rs = page_start; + pcpu_next_unpop(chunk, &rs, &re, page_end); + if (rs == page_start && re == page_end) + return; + + /* immutable chunks can't be depopulated */ + WARN_ON(chunk->immutable); + + /* + * If control reaches here, there must have been at least one + * successful population attempt so the temp pages array must + * be available now. + */ + pages = pcpu_get_pages_and_bitmap(chunk, &populated, false); + BUG_ON(!pages); + + /* unmap and free */ + pcpu_pre_unmap_flush(chunk, page_start, page_end); + + pcpu_for_each_pop_region(chunk, rs, re, page_start, page_end) + pcpu_unmap_pages(chunk, pages, populated, rs, re); + + /* no need to flush tlb, vmalloc will handle it lazily */ + + pcpu_for_each_pop_region(chunk, rs, re, page_start, page_end) + pcpu_free_pages(chunk, pages, populated, rs, re); + + /* commit new bitmap */ + bitmap_copy(chunk->populated, populated, pcpu_unit_pages); +} + +static struct pcpu_chunk *pcpu_create_chunk(void) +{ + struct pcpu_chunk *chunk; + struct vm_struct **vms; + + chunk = pcpu_alloc_chunk(); + if (!chunk) + return NULL; + + vms = pcpu_get_vm_areas(pcpu_group_offsets, pcpu_group_sizes, + pcpu_nr_groups, pcpu_atom_size, GFP_KERNEL); + if (!vms) { + pcpu_free_chunk(chunk); + return NULL; + } + + chunk->data = vms; + chunk->base_addr = vms[0]->addr - pcpu_group_offsets[0]; + return chunk; +} + +static void pcpu_destroy_chunk(struct pcpu_chunk *chunk) +{ + if (chunk && chunk->data) + pcpu_free_vm_areas(chunk->data, pcpu_nr_groups); + pcpu_free_chunk(chunk); +} + +static struct page *pcpu_addr_to_page(void *addr) +{ + return vmalloc_to_page(addr); +} + +static int __init pcpu_verify_alloc_info(const struct pcpu_alloc_info *ai) +{ + /* no extra restriction */ + return 0; +} diff --git a/mm/percpu.c b/mm/percpu.c index b403d7c02c67..15f680430671 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -236,15 +236,6 @@ static unsigned long __maybe_unused pcpu_chunk_addr(struct pcpu_chunk *chunk, (page_idx << PAGE_SHIFT); } -static struct page *pcpu_chunk_page(struct pcpu_chunk *chunk, - unsigned int cpu, int page_idx) -{ - /* must not be used on pre-mapped chunk */ - WARN_ON(chunk->immutable); - - return vmalloc_to_page((void *)pcpu_chunk_addr(chunk, cpu, page_idx)); -} - static void __maybe_unused pcpu_next_unpop(struct pcpu_chunk *chunk, int *rs, int *re, int end) { @@ -641,425 +632,29 @@ static void pcpu_free_chunk(struct pcpu_chunk *chunk) kfree(chunk); } -/** - * pcpu_get_pages_and_bitmap - get temp pages array and bitmap - * @chunk: chunk of interest - * @bitmapp: output parameter for bitmap - * @may_alloc: may allocate the array - * - * Returns pointer to array of pointers to struct page and bitmap, - * both of which can be indexed with pcpu_page_idx(). The returned - * array is cleared to zero and *@bitmapp is copied from - * @chunk->populated. Note that there is only one array and bitmap - * and access exclusion is the caller's responsibility. - * - * CONTEXT: - * pcpu_alloc_mutex and does GFP_KERNEL allocation if @may_alloc. - * Otherwise, don't care. - * - * RETURNS: - * Pointer to temp pages array on success, NULL on failure. - */ -static struct page **pcpu_get_pages_and_bitmap(struct pcpu_chunk *chunk, - unsigned long **bitmapp, - bool may_alloc) -{ - static struct page **pages; - static unsigned long *bitmap; - size_t pages_size = pcpu_nr_units * pcpu_unit_pages * sizeof(pages[0]); - size_t bitmap_size = BITS_TO_LONGS(pcpu_unit_pages) * - sizeof(unsigned long); - - if (!pages || !bitmap) { - if (may_alloc && !pages) - pages = pcpu_mem_alloc(pages_size); - if (may_alloc && !bitmap) - bitmap = pcpu_mem_alloc(bitmap_size); - if (!pages || !bitmap) - return NULL; - } - - memset(pages, 0, pages_size); - bitmap_copy(bitmap, chunk->populated, pcpu_unit_pages); - - *bitmapp = bitmap; - return pages; -} - -/** - * pcpu_free_pages - free pages which were allocated for @chunk - * @chunk: chunk pages were allocated for - * @pages: array of pages to be freed, indexed by pcpu_page_idx() - * @populated: populated bitmap - * @page_start: page index of the first page to be freed - * @page_end: page index of the last page to be freed + 1 - * - * Free pages [@page_start and @page_end) in @pages for all units. - * The pages were allocated for @chunk. - */ -static void pcpu_free_pages(struct pcpu_chunk *chunk, - struct page **pages, unsigned long *populated, - int page_start, int page_end) -{ - unsigned int cpu; - int i; - - for_each_possible_cpu(cpu) { - for (i = page_start; i < page_end; i++) { - struct page *page = pages[pcpu_page_idx(cpu, i)]; - - if (page) - __free_page(page); - } - } -} - -/** - * pcpu_alloc_pages - allocates pages for @chunk - * @chunk: target chunk - * @pages: array to put the allocated pages into, indexed by pcpu_page_idx() - * @populated: populated bitmap - * @page_start: page index of the first page to be allocated - * @page_end: page index of the last page to be allocated + 1 - * - * Allocate pages [@page_start,@page_end) into @pages for all units. - * The allocation is for @chunk. Percpu core doesn't care about the - * content of @pages and will pass it verbatim to pcpu_map_pages(). - */ -static int pcpu_alloc_pages(struct pcpu_chunk *chunk, - struct page **pages, unsigned long *populated, - int page_start, int page_end) -{ - const gfp_t gfp = GFP_KERNEL | __GFP_HIGHMEM | __GFP_COLD; - unsigned int cpu; - int i; - - for_each_possible_cpu(cpu) { - for (i = page_start; i < page_end; i++) { - struct page **pagep = &pages[pcpu_page_idx(cpu, i)]; - - *pagep = alloc_pages_node(cpu_to_node(cpu), gfp, 0); - if (!*pagep) { - pcpu_free_pages(chunk, pages, populated, - page_start, page_end); - return -ENOMEM; - } - } - } - return 0; -} - -/** - * pcpu_pre_unmap_flush - flush cache prior to unmapping - * @chunk: chunk the regions to be flushed belongs to - * @page_start: page index of the first page to be flushed - * @page_end: page index of the last page to be flushed + 1 - * - * Pages in [@page_start,@page_end) of @chunk are about to be - * unmapped. Flush cache. As each flushing trial can be very - * expensive, issue flush on the whole region at once rather than - * doing it for each cpu. This could be an overkill but is more - * scalable. - */ -static void pcpu_pre_unmap_flush(struct pcpu_chunk *chunk, - int page_start, int page_end) -{ - flush_cache_vunmap( - pcpu_chunk_addr(chunk, pcpu_first_unit_cpu, page_start), - pcpu_chunk_addr(chunk, pcpu_last_unit_cpu, page_end)); -} - -static void __pcpu_unmap_pages(unsigned long addr, int nr_pages) -{ - unmap_kernel_range_noflush(addr, nr_pages << PAGE_SHIFT); -} - -/** - * pcpu_unmap_pages - unmap pages out of a pcpu_chunk - * @chunk: chunk of interest - * @pages: pages array which can be used to pass information to free - * @populated: populated bitmap - * @page_start: page index of the first page to unmap - * @page_end: page index of the last page to unmap + 1 - * - * For each cpu, unmap pages [@page_start,@page_end) out of @chunk. - * Corresponding elements in @pages were cleared by the caller and can - * be used to carry information to pcpu_free_pages() which will be - * called after all unmaps are finished. The caller should call - * proper pre/post flush functions. - */ -static void pcpu_unmap_pages(struct pcpu_chunk *chunk, - struct page **pages, unsigned long *populated, - int page_start, int page_end) -{ - unsigned int cpu; - int i; - - for_each_possible_cpu(cpu) { - for (i = page_start; i < page_end; i++) { - struct page *page; - - page = pcpu_chunk_page(chunk, cpu, i); - WARN_ON(!page); - pages[pcpu_page_idx(cpu, i)] = page; - } - __pcpu_unmap_pages(pcpu_chunk_addr(chunk, cpu, page_start), - page_end - page_start); - } - - for (i = page_start; i < page_end; i++) - __clear_bit(i, populated); -} - -/** - * pcpu_post_unmap_tlb_flush - flush TLB after unmapping - * @chunk: pcpu_chunk the regions to be flushed belong to - * @page_start: page index of the first page to be flushed - * @page_end: page index of the last page to be flushed + 1 - * - * Pages [@page_start,@page_end) of @chunk have been unmapped. Flush - * TLB for the regions. This can be skipped if the area is to be - * returned to vmalloc as vmalloc will handle TLB flushing lazily. - * - * As with pcpu_pre_unmap_flush(), TLB flushing also is done at once - * for the whole region. - */ -static void pcpu_post_unmap_tlb_flush(struct pcpu_chunk *chunk, - int page_start, int page_end) -{ - flush_tlb_kernel_range( - pcpu_chunk_addr(chunk, pcpu_first_unit_cpu, page_start), - pcpu_chunk_addr(chunk, pcpu_last_unit_cpu, page_end)); -} - -static int __pcpu_map_pages(unsigned long addr, struct page **pages, - int nr_pages) -{ - return map_kernel_range_noflush(addr, nr_pages << PAGE_SHIFT, - PAGE_KERNEL, pages); -} - -/** - * pcpu_map_pages - map pages into a pcpu_chunk - * @chunk: chunk of interest - * @pages: pages array containing pages to be mapped - * @populated: populated bitmap - * @page_start: page index of the first page to map - * @page_end: page index of the last page to map + 1 - * - * For each cpu, map pages [@page_start,@page_end) into @chunk. The - * caller is responsible for calling pcpu_post_map_flush() after all - * mappings are complete. - * - * This function is responsible for setting corresponding bits in - * @chunk->populated bitmap and whatever is necessary for reverse - * lookup (addr -> chunk). - */ -static int pcpu_map_pages(struct pcpu_chunk *chunk, - struct page **pages, unsigned long *populated, - int page_start, int page_end) -{ - unsigned int cpu, tcpu; - int i, err; - - for_each_possible_cpu(cpu) { - err = __pcpu_map_pages(pcpu_chunk_addr(chunk, cpu, page_start), - &pages[pcpu_page_idx(cpu, page_start)], - page_end - page_start); - if (err < 0) - goto err; - } - - /* mapping successful, link chunk and mark populated */ - for (i = page_start; i < page_end; i++) { - for_each_possible_cpu(cpu) - pcpu_set_page_chunk(pages[pcpu_page_idx(cpu, i)], - chunk); - __set_bit(i, populated); - } - - return 0; - -err: - for_each_possible_cpu(tcpu) { - if (tcpu == cpu) - break; - __pcpu_unmap_pages(pcpu_chunk_addr(chunk, tcpu, page_start), - page_end - page_start); - } - return err; -} - -/** - * pcpu_post_map_flush - flush cache after mapping - * @chunk: pcpu_chunk the regions to be flushed belong to - * @page_start: page index of the first page to be flushed - * @page_end: page index of the last page to be flushed + 1 - * - * Pages [@page_start,@page_end) of @chunk have been mapped. Flush - * cache. - * - * As with pcpu_pre_unmap_flush(), TLB flushing also is done at once - * for the whole region. - */ -static void pcpu_post_map_flush(struct pcpu_chunk *chunk, - int page_start, int page_end) -{ - flush_cache_vmap( - pcpu_chunk_addr(chunk, pcpu_first_unit_cpu, page_start), - pcpu_chunk_addr(chunk, pcpu_last_unit_cpu, page_end)); -} - -/** - * pcpu_depopulate_chunk - depopulate and unmap an area of a pcpu_chunk - * @chunk: chunk to depopulate - * @off: offset to the area to depopulate - * @size: size of the area to depopulate in bytes - * @flush: whether to flush cache and tlb or not - * - * For each cpu, depopulate and unmap pages [@page_start,@page_end) - * from @chunk. If @flush is true, vcache is flushed before unmapping - * and tlb after. - * - * CONTEXT: - * pcpu_alloc_mutex. - */ -static void pcpu_depopulate_chunk(struct pcpu_chunk *chunk, int off, int size) -{ - int page_start = PFN_DOWN(off); - int page_end = PFN_UP(off + size); - struct page **pages; - unsigned long *populated; - int rs, re; - - /* quick path, check whether it's empty already */ - rs = page_start; - pcpu_next_unpop(chunk, &rs, &re, page_end); - if (rs == page_start && re == page_end) - return; - - /* immutable chunks can't be depopulated */ - WARN_ON(chunk->immutable); - - /* - * If control reaches here, there must have been at least one - * successful population attempt so the temp pages array must - * be available now. - */ - pages = pcpu_get_pages_and_bitmap(chunk, &populated, false); - BUG_ON(!pages); - - /* unmap and free */ - pcpu_pre_unmap_flush(chunk, page_start, page_end); - - pcpu_for_each_pop_region(chunk, rs, re, page_start, page_end) - pcpu_unmap_pages(chunk, pages, populated, rs, re); - - /* no need to flush tlb, vmalloc will handle it lazily */ - - pcpu_for_each_pop_region(chunk, rs, re, page_start, page_end) - pcpu_free_pages(chunk, pages, populated, rs, re); - - /* commit new bitmap */ - bitmap_copy(chunk->populated, populated, pcpu_unit_pages); -} - -/** - * pcpu_populate_chunk - populate and map an area of a pcpu_chunk - * @chunk: chunk of interest - * @off: offset to the area to populate - * @size: size of the area to populate in bytes - * - * For each cpu, populate and map pages [@page_start,@page_end) into - * @chunk. The area is cleared on return. - * - * CONTEXT: - * pcpu_alloc_mutex, does GFP_KERNEL allocation. +/* + * Chunk management implementation. + * + * To allow different implementations, chunk alloc/free and + * [de]population are implemented in a separate file which is pulled + * into this file and compiled together. The following functions + * should be implemented. + * + * pcpu_populate_chunk - populate the specified range of a chunk + * pcpu_depopulate_chunk - depopulate the specified range of a chunk + * pcpu_create_chunk - create a new chunk + * pcpu_destroy_chunk - destroy a chunk, always preceded by full depop + * pcpu_addr_to_page - translate address to physical address + * pcpu_verify_alloc_info - check alloc_info is acceptable during init */ -static int pcpu_populate_chunk(struct pcpu_chunk *chunk, int off, int size) -{ - int page_start = PFN_DOWN(off); - int page_end = PFN_UP(off + size); - int free_end = page_start, unmap_end = page_start; - struct page **pages; - unsigned long *populated; - unsigned int cpu; - int rs, re, rc; - - /* quick path, check whether all pages are already there */ - rs = page_start; - pcpu_next_pop(chunk, &rs, &re, page_end); - if (rs == page_start && re == page_end) - goto clear; - - /* need to allocate and map pages, this chunk can't be immutable */ - WARN_ON(chunk->immutable); - - pages = pcpu_get_pages_and_bitmap(chunk, &populated, true); - if (!pages) - return -ENOMEM; - - /* alloc and map */ - pcpu_for_each_unpop_region(chunk, rs, re, page_start, page_end) { - rc = pcpu_alloc_pages(chunk, pages, populated, rs, re); - if (rc) - goto err_free; - free_end = re; - } - - pcpu_for_each_unpop_region(chunk, rs, re, page_start, page_end) { - rc = pcpu_map_pages(chunk, pages, populated, rs, re); - if (rc) - goto err_unmap; - unmap_end = re; - } - pcpu_post_map_flush(chunk, page_start, page_end); - - /* commit new bitmap */ - bitmap_copy(chunk->populated, populated, pcpu_unit_pages); -clear: - for_each_possible_cpu(cpu) - memset((void *)pcpu_chunk_addr(chunk, cpu, 0) + off, 0, size); - return 0; - -err_unmap: - pcpu_pre_unmap_flush(chunk, page_start, unmap_end); - pcpu_for_each_unpop_region(chunk, rs, re, page_start, unmap_end) - pcpu_unmap_pages(chunk, pages, populated, rs, re); - pcpu_post_unmap_tlb_flush(chunk, page_start, unmap_end); -err_free: - pcpu_for_each_unpop_region(chunk, rs, re, page_start, free_end) - pcpu_free_pages(chunk, pages, populated, rs, re); - return rc; -} +static int pcpu_populate_chunk(struct pcpu_chunk *chunk, int off, int size); +static void pcpu_depopulate_chunk(struct pcpu_chunk *chunk, int off, int size); +static struct pcpu_chunk *pcpu_create_chunk(void); +static void pcpu_destroy_chunk(struct pcpu_chunk *chunk); +static struct page *pcpu_addr_to_page(void *addr); +static int __init pcpu_verify_alloc_info(const struct pcpu_alloc_info *ai); -static void pcpu_destroy_chunk(struct pcpu_chunk *chunk) -{ - if (chunk && chunk->data) - pcpu_free_vm_areas(chunk->data, pcpu_nr_groups); - pcpu_free_chunk(chunk); -} - -static struct pcpu_chunk *pcpu_create_chunk(void) -{ - struct pcpu_chunk *chunk; - struct vm_struct **vms; - - chunk = pcpu_alloc_chunk(); - if (!chunk) - return NULL; - - vms = pcpu_get_vm_areas(pcpu_group_offsets, pcpu_group_sizes, - pcpu_nr_groups, pcpu_atom_size, GFP_KERNEL); - if (!vms) { - pcpu_free_chunk(chunk); - return NULL; - } - - chunk->data = vms; - chunk->base_addr = vms[0]->addr - pcpu_group_offsets[0]; - return chunk; -} +#include "percpu-vm.c" /** * pcpu_chunk_addr_search - determine chunk containing specified address @@ -1086,7 +681,7 @@ static struct pcpu_chunk *pcpu_chunk_addr_search(void *addr) * there's no need to worry about preemption or cpu hotplug. */ addr += pcpu_unit_offsets[raw_smp_processor_id()]; - return pcpu_get_page_chunk(vmalloc_to_page(addr)); + return pcpu_get_page_chunk(pcpu_addr_to_page(addr)); } /** @@ -1386,7 +981,7 @@ phys_addr_t per_cpu_ptr_to_phys(void *addr) else return page_to_phys(vmalloc_to_page(addr)); } else - return page_to_phys(vmalloc_to_page(addr)); + return page_to_phys(pcpu_addr_to_page(addr)); } static inline size_t pcpu_calc_fc_sizes(size_t static_size, @@ -1758,6 +1353,7 @@ int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai, PCPU_SETUP_BUG_ON(ai->unit_size < size_sum); PCPU_SETUP_BUG_ON(ai->unit_size & ~PAGE_MASK); PCPU_SETUP_BUG_ON(ai->unit_size < PCPU_MIN_UNIT_SIZE); + PCPU_SETUP_BUG_ON(pcpu_verify_alloc_info(ai) < 0); /* process group information and build config tables accordingly */ group_offsets = alloc_bootmem(ai->nr_groups * sizeof(group_offsets[0])); |