The patch titled Subject: mm: add support for direct_IO to highmem pages has been added to the -mm tree. Its filename is mm-add-support-for-direct_io-to-highmem-pages.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Mel Gorman <mgorman@xxxxxxx> Subject: mm: add support for direct_IO to highmem pages The patch "mm: add support for a filesystem to activate swap files and use direct_IO for writing swap pages" added support for using direct_IO to write swap pages but it is insufficient for highmem pages. To support highmem pages, this patch kmaps() the page before calling the direct_IO() handler. As direct_IO deals with virtual addresses an additional helper is necessary for get_kernel_pages() to lookup the struct page for a kmap virtual address. Signed-off-by: Mel Gorman <mgorman@xxxxxxx> Acked-by: Rik van Riel <riel@xxxxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx> Cc: David S. Miller <davem@xxxxxxxxxxxxx> Cc: Eric B Munson <emunson@xxxxxxxxx> Cc: Eric Paris <eparis@xxxxxxxxxx> Cc: James Morris <jmorris@xxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxx> Cc: Mike Christie <michaelc@xxxxxxxxxxx> Cc: Neil Brown <neilb@xxxxxxx> Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> Cc: Sebastian Andrzej Siewior <sebastian@xxxxxxxxxxxxx> Cc: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx> Cc: Xiaotian Feng <dfeng@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/highmem.h | 7 +++++++ mm/highmem.c | 12 ++++++++++++ mm/memory.c | 3 +-- mm/page_io.c | 3 ++- 4 files changed, 22 insertions(+), 3 deletions(-) diff -puN include/linux/highmem.h~mm-add-support-for-direct_io-to-highmem-pages include/linux/highmem.h --- a/include/linux/highmem.h~mm-add-support-for-direct_io-to-highmem-pages +++ a/include/linux/highmem.h @@ -39,10 +39,17 @@ extern unsigned long totalhigh_pages; void kmap_flush_unused(void); +struct page *kmap_to_page(void *addr); + #else /* CONFIG_HIGHMEM */ static inline unsigned int nr_free_highpages(void) { return 0; } +static inline struct page *kmap_to_page(void *addr) +{ + return virt_to_page(addr); +} + #define totalhigh_pages 0UL #ifndef ARCH_HAS_KMAP diff -puN mm/highmem.c~mm-add-support-for-direct_io-to-highmem-pages mm/highmem.c --- a/mm/highmem.c~mm-add-support-for-direct_io-to-highmem-pages +++ a/mm/highmem.c @@ -94,6 +94,18 @@ static DECLARE_WAIT_QUEUE_HEAD(pkmap_map do { spin_unlock(&kmap_lock); (void)(flags); } while (0) #endif +struct page *kmap_to_page(void *vaddr) +{ + unsigned long addr = (unsigned long)vaddr; + + if (addr >= PKMAP_ADDR(0) && addr <= PKMAP_ADDR(LAST_PKMAP)) { + int i = (addr - PKMAP_ADDR(0)) >> PAGE_SHIFT; + return pte_page(pkmap_page_table[i]); + } + + return virt_to_page(addr); +} + static void flush_all_zero_pkmaps(void) { int i; diff -puN mm/memory.c~mm-add-support-for-direct_io-to-highmem-pages mm/memory.c --- a/mm/memory.c~mm-add-support-for-direct_io-to-highmem-pages +++ a/mm/memory.c @@ -1864,8 +1864,7 @@ int get_kernel_pages(const struct kvec * if (WARN_ON(kiov[seg].iov_len != PAGE_SIZE)) return seg; - /* virt_to_page sanity checks the PFN */ - pages[seg] = virt_to_page(kiov[seg].iov_base); + pages[seg] = kmap_to_page(kiov[seg].iov_base); page_cache_get(pages[seg]); } diff -puN mm/page_io.c~mm-add-support-for-direct_io-to-highmem-pages mm/page_io.c --- a/mm/page_io.c~mm-add-support-for-direct_io-to-highmem-pages +++ a/mm/page_io.c @@ -205,7 +205,7 @@ int swap_writepage(struct page *page, st struct file *swap_file = sis->swap_file; struct address_space *mapping = swap_file->f_mapping; struct iovec iov = { - .iov_base = page_address(page), + .iov_base = kmap(page), .iov_len = PAGE_SIZE, }; @@ -218,6 +218,7 @@ int swap_writepage(struct page *page, st ret = mapping->a_ops->direct_IO(KERNEL_WRITE, &kiocb, &iov, kiocb.ki_pos, 1); + kunmap(page); if (ret == PAGE_SIZE) { count_vm_event(PSWPOUT); ret = 0; _ Subject: Subject: mm: add support for direct_IO to highmem pages Patches currently in -mm which might be from mgorman@xxxxxxx are origin.patch linux-next.patch memcg-prevent-oom-with-too-many-dirty-pages.patch memcg-prevent-oom-with-too-many-dirty-pages-fix.patch mm-do-not-use-page_count-without-a-page-pin.patch mm-clean-up-__count_immobile_pages.patch mm-hotplug-correctly-setup-fallback-zonelists-when-creating-new-pgdat.patch mm-hotplug-correctly-add-new-zone-to-all-other-nodes-zone-lists.patch mm-hotplug-free-zone-pageset-when-a-zone-becomes-empty.patch mm-hotplug-mark-memory-hotplug-code-in-page_allocc-as-__meminit.patch mm-factor-out-memory-isolate-functions.patch mm-bug-fix-free-page-check-in-zone_watermark_ok.patch memory-hotplug-fix-kswapd-looping-forever-problem.patch memory-hotplug-fix-kswapd-looping-forever-problem-fix.patch mm-slb-add-knowledge-of-pfmemalloc-reserve-pages.patch mm-slub-optimise-the-slub-fast-path-to-avoid-pfmemalloc-checks.patch mm-introduce-__gfp_memalloc-to-allow-access-to-emergency-reserves.patch mm-allow-pf_memalloc-from-softirq-context.patch mm-only-set-page-pfmemalloc-when-alloc_no_watermarks-was-used.patch mm-ignore-mempolicies-when-using-alloc_no_watermark.patch net-introduce-sk_gfp_atomic-to-allow-addition-of-gfp-flags-depending-on-the-individual-socket.patch netvm-allow-the-use-of-__gfp_memalloc-by-specific-sockets.patch netvm-allow-skb-allocation-to-use-pfmemalloc-reserves.patch netvm-propagate-page-pfmemalloc-to-skb.patch netvm-propagate-page-pfmemalloc-from-skb_alloc_page-to-skb.patch netvm-set-pf_memalloc-as-appropriate-during-skb-processing.patch mm-micro-optimise-slab-to-avoid-a-function-call.patch nbd-set-sock_memalloc-for-access-to-pfmemalloc-reserves.patch mm-throttle-direct-reclaimers-if-pf_memalloc-reserves-are-low-and-swap-is-backed-by-network-storage.patch mm-account-for-the-number-of-times-direct-reclaimers-get-throttled.patch netvm-prevent-a-stream-specific-deadlock.patch selinux-tag-avc-cache-alloc-as-non-critical.patch mm-methods-for-teaching-filesystems-about-pg_swapcache-pages.patch mm-add-support-for-a-filesystem-to-activate-swap-files-and-use-direct_io-for-writing-swap-pages.patch mm-swap-implement-generic-handler-for-swap_activate.patch mm-add-get_kernel_page-for-pinning-of-kernel-addresses-for-i-o.patch mm-add-support-for-direct_io-to-highmem-pages.patch nfs-teach-the-nfs-client-how-to-treat-pg_swapcache-pages.patch nfs-disable-data-cache-revalidation-for-swapfiles.patch nfs-enable-swap-on-nfs.patch nfs-prevent-page-allocator-recursions-with-swap-over-nfs.patch swapfile-avoid-dereferencing-bd_disk-during-swap_entry_free-for-network-storage.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html