mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2024-12-29 09:13:38 +00:00
io_uring: move mapping/allocation helpers to a separate file
Move the related code from io_uring.c into memmap.c. No functional changes in this patch, just cleaning it up a bit now that the full transition is done. Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
parent
18595c0a58
commit
f15ed8b4d0
@ -8,7 +8,8 @@ obj-$(CONFIG_IO_URING) += io_uring.o opdef.o kbuf.o rsrc.o notif.o \
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xattr.o nop.o fs.o splice.o sync.o \
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msg_ring.o advise.o openclose.o \
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epoll.o statx.o timeout.o fdinfo.o \
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cancel.o waitid.o register.o truncate.o
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cancel.o waitid.o register.o \
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truncate.o memmap.o
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obj-$(CONFIG_IO_WQ) += io-wq.o
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obj-$(CONFIG_FUTEX) += futex.o
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obj-$(CONFIG_NET_RX_BUSY_POLL) += napi.o
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@ -95,6 +95,7 @@
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#include "futex.h"
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#include "napi.h"
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#include "uring_cmd.h"
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#include "memmap.h"
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#include "timeout.h"
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#include "poll.h"
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@ -2597,111 +2598,6 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
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return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0;
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}
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void io_pages_unmap(void *ptr, struct page ***pages, unsigned short *npages,
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bool put_pages)
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{
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bool do_vunmap = false;
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if (!ptr)
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return;
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if (put_pages && *npages) {
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struct page **to_free = *pages;
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int i;
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/*
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* Only did vmap for the non-compound multiple page case.
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* For the compound page, we just need to put the head.
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*/
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if (PageCompound(to_free[0]))
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*npages = 1;
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else if (*npages > 1)
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do_vunmap = true;
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for (i = 0; i < *npages; i++)
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put_page(to_free[i]);
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}
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if (do_vunmap)
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vunmap(ptr);
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kvfree(*pages);
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*pages = NULL;
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*npages = 0;
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}
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static void io_pages_free(struct page ***pages, int npages)
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{
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struct page **page_array = *pages;
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if (!page_array)
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return;
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unpin_user_pages(page_array, npages);
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kvfree(page_array);
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*pages = NULL;
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}
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struct page **io_pin_pages(unsigned long uaddr, unsigned long len, int *npages)
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{
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unsigned long start, end, nr_pages;
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struct page **pages;
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int ret;
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end = (uaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
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start = uaddr >> PAGE_SHIFT;
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nr_pages = end - start;
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if (WARN_ON_ONCE(!nr_pages))
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return ERR_PTR(-EINVAL);
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pages = kvmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL);
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if (!pages)
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return ERR_PTR(-ENOMEM);
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ret = pin_user_pages_fast(uaddr, nr_pages, FOLL_WRITE | FOLL_LONGTERM,
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pages);
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/* success, mapped all pages */
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if (ret == nr_pages) {
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*npages = nr_pages;
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return pages;
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}
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/* partial map, or didn't map anything */
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if (ret >= 0) {
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/* if we did partial map, release any pages we did get */
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if (ret)
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unpin_user_pages(pages, ret);
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ret = -EFAULT;
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}
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kvfree(pages);
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return ERR_PTR(ret);
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}
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static void *__io_uaddr_map(struct page ***pages, unsigned short *npages,
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unsigned long uaddr, size_t size)
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{
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struct page **page_array;
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unsigned int nr_pages;
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void *page_addr;
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*npages = 0;
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if (uaddr & (PAGE_SIZE - 1) || !size)
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return ERR_PTR(-EINVAL);
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nr_pages = 0;
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page_array = io_pin_pages(uaddr, size, &nr_pages);
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if (IS_ERR(page_array))
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return page_array;
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page_addr = vmap(page_array, nr_pages, VM_MAP, PAGE_KERNEL);
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if (page_addr) {
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*pages = page_array;
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*npages = nr_pages;
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return page_addr;
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}
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io_pages_free(&page_array, nr_pages);
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return ERR_PTR(-ENOMEM);
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}
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static void *io_rings_map(struct io_ring_ctx *ctx, unsigned long uaddr,
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size_t size)
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{
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@ -2736,80 +2632,6 @@ static void io_rings_free(struct io_ring_ctx *ctx)
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ctx->sq_sqes = NULL;
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}
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static void *io_mem_alloc_compound(struct page **pages, int nr_pages,
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size_t size, gfp_t gfp)
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{
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struct page *page;
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int i, order;
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order = get_order(size);
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if (order > MAX_PAGE_ORDER)
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return ERR_PTR(-ENOMEM);
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else if (order)
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gfp |= __GFP_COMP;
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page = alloc_pages(gfp, order);
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if (!page)
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return ERR_PTR(-ENOMEM);
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for (i = 0; i < nr_pages; i++)
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pages[i] = page + i;
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return page_address(page);
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}
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static void *io_mem_alloc_single(struct page **pages, int nr_pages, size_t size,
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gfp_t gfp)
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{
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void *ret;
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int i;
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for (i = 0; i < nr_pages; i++) {
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pages[i] = alloc_page(gfp);
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if (!pages[i])
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goto err;
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}
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ret = vmap(pages, nr_pages, VM_MAP, PAGE_KERNEL);
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if (ret)
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return ret;
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err:
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while (i--)
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put_page(pages[i]);
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return ERR_PTR(-ENOMEM);
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}
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void *io_pages_map(struct page ***out_pages, unsigned short *npages,
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size_t size)
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{
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gfp_t gfp = GFP_KERNEL_ACCOUNT | __GFP_ZERO | __GFP_NOWARN;
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struct page **pages;
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int nr_pages;
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void *ret;
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nr_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
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pages = kvmalloc_array(nr_pages, sizeof(struct page *), gfp);
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if (!pages)
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return ERR_PTR(-ENOMEM);
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ret = io_mem_alloc_compound(pages, nr_pages, size, gfp);
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if (!IS_ERR(ret))
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goto done;
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ret = io_mem_alloc_single(pages, nr_pages, size, gfp);
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if (!IS_ERR(ret)) {
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done:
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*out_pages = pages;
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*npages = nr_pages;
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return ret;
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}
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kvfree(pages);
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*out_pages = NULL;
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*npages = 0;
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return ret;
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}
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static unsigned long rings_size(struct io_ring_ctx *ctx, unsigned int sq_entries,
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unsigned int cq_entries, size_t *sq_offset)
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{
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@ -3370,149 +3192,6 @@ void __io_uring_cancel(bool cancel_all)
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io_uring_cancel_generic(cancel_all, NULL);
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}
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static void *io_uring_validate_mmap_request(struct file *file,
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loff_t pgoff, size_t sz)
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{
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struct io_ring_ctx *ctx = file->private_data;
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loff_t offset = pgoff << PAGE_SHIFT;
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switch ((pgoff << PAGE_SHIFT) & IORING_OFF_MMAP_MASK) {
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case IORING_OFF_SQ_RING:
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case IORING_OFF_CQ_RING:
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/* Don't allow mmap if the ring was setup without it */
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if (ctx->flags & IORING_SETUP_NO_MMAP)
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return ERR_PTR(-EINVAL);
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return ctx->rings;
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case IORING_OFF_SQES:
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/* Don't allow mmap if the ring was setup without it */
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if (ctx->flags & IORING_SETUP_NO_MMAP)
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return ERR_PTR(-EINVAL);
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return ctx->sq_sqes;
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case IORING_OFF_PBUF_RING: {
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struct io_buffer_list *bl;
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unsigned int bgid;
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void *ptr;
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bgid = (offset & ~IORING_OFF_MMAP_MASK) >> IORING_OFF_PBUF_SHIFT;
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bl = io_pbuf_get_bl(ctx, bgid);
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if (IS_ERR(bl))
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return bl;
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ptr = bl->buf_ring;
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io_put_bl(ctx, bl);
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return ptr;
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}
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}
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return ERR_PTR(-EINVAL);
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}
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int io_uring_mmap_pages(struct io_ring_ctx *ctx, struct vm_area_struct *vma,
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struct page **pages, int npages)
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{
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unsigned long nr_pages = npages;
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vm_flags_set(vma, VM_DONTEXPAND);
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return vm_insert_pages(vma, vma->vm_start, pages, &nr_pages);
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}
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#ifdef CONFIG_MMU
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static __cold int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
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{
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struct io_ring_ctx *ctx = file->private_data;
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size_t sz = vma->vm_end - vma->vm_start;
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long offset = vma->vm_pgoff << PAGE_SHIFT;
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void *ptr;
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ptr = io_uring_validate_mmap_request(file, vma->vm_pgoff, sz);
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if (IS_ERR(ptr))
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return PTR_ERR(ptr);
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switch (offset & IORING_OFF_MMAP_MASK) {
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case IORING_OFF_SQ_RING:
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case IORING_OFF_CQ_RING:
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return io_uring_mmap_pages(ctx, vma, ctx->ring_pages,
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ctx->n_ring_pages);
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case IORING_OFF_SQES:
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return io_uring_mmap_pages(ctx, vma, ctx->sqe_pages,
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ctx->n_sqe_pages);
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case IORING_OFF_PBUF_RING:
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return io_pbuf_mmap(file, vma);
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}
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return -EINVAL;
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}
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static unsigned long io_uring_mmu_get_unmapped_area(struct file *filp,
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unsigned long addr, unsigned long len,
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unsigned long pgoff, unsigned long flags)
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{
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void *ptr;
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/*
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* Do not allow to map to user-provided address to avoid breaking the
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* aliasing rules. Userspace is not able to guess the offset address of
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* kernel kmalloc()ed memory area.
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*/
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if (addr)
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return -EINVAL;
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ptr = io_uring_validate_mmap_request(filp, pgoff, len);
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if (IS_ERR(ptr))
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return -ENOMEM;
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/*
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* Some architectures have strong cache aliasing requirements.
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* For such architectures we need a coherent mapping which aliases
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* kernel memory *and* userspace memory. To achieve that:
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* - use a NULL file pointer to reference physical memory, and
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* - use the kernel virtual address of the shared io_uring context
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* (instead of the userspace-provided address, which has to be 0UL
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* anyway).
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* - use the same pgoff which the get_unmapped_area() uses to
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* calculate the page colouring.
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* For architectures without such aliasing requirements, the
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* architecture will return any suitable mapping because addr is 0.
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*/
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filp = NULL;
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flags |= MAP_SHARED;
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pgoff = 0; /* has been translated to ptr above */
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#ifdef SHM_COLOUR
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addr = (uintptr_t) ptr;
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pgoff = addr >> PAGE_SHIFT;
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#else
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addr = 0UL;
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#endif
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return current->mm->get_unmapped_area(filp, addr, len, pgoff, flags);
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}
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#else /* !CONFIG_MMU */
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static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
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{
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return is_nommu_shared_mapping(vma->vm_flags) ? 0 : -EINVAL;
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}
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static unsigned int io_uring_nommu_mmap_capabilities(struct file *file)
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{
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return NOMMU_MAP_DIRECT | NOMMU_MAP_READ | NOMMU_MAP_WRITE;
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}
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static unsigned long io_uring_nommu_get_unmapped_area(struct file *file,
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unsigned long addr, unsigned long len,
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unsigned long pgoff, unsigned long flags)
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{
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void *ptr;
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ptr = io_uring_validate_mmap_request(file, pgoff, len);
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if (IS_ERR(ptr))
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return PTR_ERR(ptr);
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return (unsigned long) ptr;
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}
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#endif /* !CONFIG_MMU */
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static int io_validate_ext_arg(unsigned flags, const void __user *argp, size_t argsz)
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{
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if (flags & IORING_ENTER_EXT_ARG) {
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@ -3695,11 +3374,9 @@ SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit,
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static const struct file_operations io_uring_fops = {
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.release = io_uring_release,
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.mmap = io_uring_mmap,
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.get_unmapped_area = io_uring_get_unmapped_area,
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#ifndef CONFIG_MMU
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.get_unmapped_area = io_uring_nommu_get_unmapped_area,
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.mmap_capabilities = io_uring_nommu_mmap_capabilities,
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#else
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.get_unmapped_area = io_uring_mmu_get_unmapped_area,
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#endif
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.poll = io_uring_poll,
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#ifdef CONFIG_PROC_FS
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@ -69,10 +69,6 @@ bool io_post_aux_cqe(struct io_ring_ctx *ctx, u64 user_data, s32 res, u32 cflags
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bool io_req_post_cqe(struct io_kiocb *req, s32 res, u32 cflags);
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void __io_commit_cqring_flush(struct io_ring_ctx *ctx);
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struct page **io_pin_pages(unsigned long ubuf, unsigned long len, int *npages);
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int io_uring_mmap_pages(struct io_ring_ctx *ctx, struct vm_area_struct *vma,
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struct page **pages, int npages);
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struct file *io_file_get_normal(struct io_kiocb *req, int fd);
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struct file *io_file_get_fixed(struct io_kiocb *req, int fd,
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unsigned issue_flags);
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@ -109,11 +105,6 @@ bool __io_alloc_req_refill(struct io_ring_ctx *ctx);
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bool io_match_task_safe(struct io_kiocb *head, struct task_struct *task,
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bool cancel_all);
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void *io_pages_map(struct page ***out_pages, unsigned short *npages,
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size_t size);
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void io_pages_unmap(void *ptr, struct page ***pages, unsigned short *npages,
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bool put_pages);
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enum {
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IO_EVENTFD_OP_SIGNAL_BIT,
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IO_EVENTFD_OP_FREE_BIT,
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@ -15,6 +15,7 @@
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#include "io_uring.h"
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#include "opdef.h"
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#include "kbuf.h"
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#include "memmap.h"
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#define IO_BUFFER_LIST_BUF_PER_PAGE (PAGE_SIZE / sizeof(struct io_uring_buf))
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|
336
io_uring/memmap.c
Normal file
336
io_uring/memmap.c
Normal file
@ -0,0 +1,336 @@
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// SPDX-License-Identifier: GPL-2.0
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/errno.h>
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#include <linux/mm.h>
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#include <linux/mman.h>
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#include <linux/slab.h>
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#include <linux/vmalloc.h>
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#include <linux/io_uring.h>
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#include <linux/io_uring_types.h>
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#include <asm/shmparam.h>
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#include "memmap.h"
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#include "kbuf.h"
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static void *io_mem_alloc_compound(struct page **pages, int nr_pages,
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size_t size, gfp_t gfp)
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{
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struct page *page;
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int i, order;
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order = get_order(size);
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if (order > MAX_PAGE_ORDER)
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return ERR_PTR(-ENOMEM);
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else if (order)
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gfp |= __GFP_COMP;
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page = alloc_pages(gfp, order);
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if (!page)
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return ERR_PTR(-ENOMEM);
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for (i = 0; i < nr_pages; i++)
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pages[i] = page + i;
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return page_address(page);
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}
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static void *io_mem_alloc_single(struct page **pages, int nr_pages, size_t size,
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gfp_t gfp)
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{
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void *ret;
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int i;
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for (i = 0; i < nr_pages; i++) {
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pages[i] = alloc_page(gfp);
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if (!pages[i])
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goto err;
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}
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ret = vmap(pages, nr_pages, VM_MAP, PAGE_KERNEL);
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if (ret)
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return ret;
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err:
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while (i--)
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put_page(pages[i]);
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return ERR_PTR(-ENOMEM);
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}
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|
||||
void *io_pages_map(struct page ***out_pages, unsigned short *npages,
|
||||
size_t size)
|
||||
{
|
||||
gfp_t gfp = GFP_KERNEL_ACCOUNT | __GFP_ZERO | __GFP_NOWARN;
|
||||
struct page **pages;
|
||||
int nr_pages;
|
||||
void *ret;
|
||||
|
||||
nr_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
|
||||
pages = kvmalloc_array(nr_pages, sizeof(struct page *), gfp);
|
||||
if (!pages)
|
||||
return ERR_PTR(-ENOMEM);
|
||||
|
||||
ret = io_mem_alloc_compound(pages, nr_pages, size, gfp);
|
||||
if (!IS_ERR(ret))
|
||||
goto done;
|
||||
|
||||
ret = io_mem_alloc_single(pages, nr_pages, size, gfp);
|
||||
if (!IS_ERR(ret)) {
|
||||
done:
|
||||
*out_pages = pages;
|
||||
*npages = nr_pages;
|
||||
return ret;
|
||||
}
|
||||
|
||||
kvfree(pages);
|
||||
*out_pages = NULL;
|
||||
*npages = 0;
|
||||
return ret;
|
||||
}
|
||||
|
||||
void io_pages_unmap(void *ptr, struct page ***pages, unsigned short *npages,
|
||||
bool put_pages)
|
||||
{
|
||||
bool do_vunmap = false;
|
||||
|
||||
if (!ptr)
|
||||
return;
|
||||
|
||||
if (put_pages && *npages) {
|
||||
struct page **to_free = *pages;
|
||||
int i;
|
||||
|
||||
/*
|
||||
* Only did vmap for the non-compound multiple page case.
|
||||
* For the compound page, we just need to put the head.
|
||||
*/
|
||||
if (PageCompound(to_free[0]))
|
||||
*npages = 1;
|
||||
else if (*npages > 1)
|
||||
do_vunmap = true;
|
||||
for (i = 0; i < *npages; i++)
|
||||
put_page(to_free[i]);
|
||||
}
|
||||
if (do_vunmap)
|
||||
vunmap(ptr);
|
||||
kvfree(*pages);
|
||||
*pages = NULL;
|
||||
*npages = 0;
|
||||
}
|
||||
|
||||
void io_pages_free(struct page ***pages, int npages)
|
||||
{
|
||||
struct page **page_array = *pages;
|
||||
|
||||
if (!page_array)
|
||||
return;
|
||||
|
||||
unpin_user_pages(page_array, npages);
|
||||
kvfree(page_array);
|
||||
*pages = NULL;
|
||||
}
|
||||
|
||||
struct page **io_pin_pages(unsigned long uaddr, unsigned long len, int *npages)
|
||||
{
|
||||
unsigned long start, end, nr_pages;
|
||||
struct page **pages;
|
||||
int ret;
|
||||
|
||||
end = (uaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
|
||||
start = uaddr >> PAGE_SHIFT;
|
||||
nr_pages = end - start;
|
||||
if (WARN_ON_ONCE(!nr_pages))
|
||||
return ERR_PTR(-EINVAL);
|
||||
|
||||
pages = kvmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL);
|
||||
if (!pages)
|
||||
return ERR_PTR(-ENOMEM);
|
||||
|
||||
ret = pin_user_pages_fast(uaddr, nr_pages, FOLL_WRITE | FOLL_LONGTERM,
|
||||
pages);
|
||||
/* success, mapped all pages */
|
||||
if (ret == nr_pages) {
|
||||
*npages = nr_pages;
|
||||
return pages;
|
||||
}
|
||||
|
||||
/* partial map, or didn't map anything */
|
||||
if (ret >= 0) {
|
||||
/* if we did partial map, release any pages we did get */
|
||||
if (ret)
|
||||
unpin_user_pages(pages, ret);
|
||||
ret = -EFAULT;
|
||||
}
|
||||
kvfree(pages);
|
||||
return ERR_PTR(ret);
|
||||
}
|
||||
|
||||
void *__io_uaddr_map(struct page ***pages, unsigned short *npages,
|
||||
unsigned long uaddr, size_t size)
|
||||
{
|
||||
struct page **page_array;
|
||||
unsigned int nr_pages;
|
||||
void *page_addr;
|
||||
|
||||
*npages = 0;
|
||||
|
||||
if (uaddr & (PAGE_SIZE - 1) || !size)
|
||||
return ERR_PTR(-EINVAL);
|
||||
|
||||
nr_pages = 0;
|
||||
page_array = io_pin_pages(uaddr, size, &nr_pages);
|
||||
if (IS_ERR(page_array))
|
||||
return page_array;
|
||||
|
||||
page_addr = vmap(page_array, nr_pages, VM_MAP, PAGE_KERNEL);
|
||||
if (page_addr) {
|
||||
*pages = page_array;
|
||||
*npages = nr_pages;
|
||||
return page_addr;
|
||||
}
|
||||
|
||||
io_pages_free(&page_array, nr_pages);
|
||||
return ERR_PTR(-ENOMEM);
|
||||
}
|
||||
|
||||
static void *io_uring_validate_mmap_request(struct file *file, loff_t pgoff,
|
||||
size_t sz)
|
||||
{
|
||||
struct io_ring_ctx *ctx = file->private_data;
|
||||
loff_t offset = pgoff << PAGE_SHIFT;
|
||||
|
||||
switch ((pgoff << PAGE_SHIFT) & IORING_OFF_MMAP_MASK) {
|
||||
case IORING_OFF_SQ_RING:
|
||||
case IORING_OFF_CQ_RING:
|
||||
/* Don't allow mmap if the ring was setup without it */
|
||||
if (ctx->flags & IORING_SETUP_NO_MMAP)
|
||||
return ERR_PTR(-EINVAL);
|
||||
return ctx->rings;
|
||||
case IORING_OFF_SQES:
|
||||
/* Don't allow mmap if the ring was setup without it */
|
||||
if (ctx->flags & IORING_SETUP_NO_MMAP)
|
||||
return ERR_PTR(-EINVAL);
|
||||
return ctx->sq_sqes;
|
||||
case IORING_OFF_PBUF_RING: {
|
||||
struct io_buffer_list *bl;
|
||||
unsigned int bgid;
|
||||
void *ptr;
|
||||
|
||||
bgid = (offset & ~IORING_OFF_MMAP_MASK) >> IORING_OFF_PBUF_SHIFT;
|
||||
bl = io_pbuf_get_bl(ctx, bgid);
|
||||
if (IS_ERR(bl))
|
||||
return bl;
|
||||
ptr = bl->buf_ring;
|
||||
io_put_bl(ctx, bl);
|
||||
return ptr;
|
||||
}
|
||||
}
|
||||
|
||||
return ERR_PTR(-EINVAL);
|
||||
}
|
||||
|
||||
int io_uring_mmap_pages(struct io_ring_ctx *ctx, struct vm_area_struct *vma,
|
||||
struct page **pages, int npages)
|
||||
{
|
||||
unsigned long nr_pages = npages;
|
||||
|
||||
vm_flags_set(vma, VM_DONTEXPAND);
|
||||
return vm_insert_pages(vma, vma->vm_start, pages, &nr_pages);
|
||||
}
|
||||
|
||||
#ifdef CONFIG_MMU
|
||||
|
||||
__cold int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
|
||||
{
|
||||
struct io_ring_ctx *ctx = file->private_data;
|
||||
size_t sz = vma->vm_end - vma->vm_start;
|
||||
long offset = vma->vm_pgoff << PAGE_SHIFT;
|
||||
void *ptr;
|
||||
|
||||
ptr = io_uring_validate_mmap_request(file, vma->vm_pgoff, sz);
|
||||
if (IS_ERR(ptr))
|
||||
return PTR_ERR(ptr);
|
||||
|
||||
switch (offset & IORING_OFF_MMAP_MASK) {
|
||||
case IORING_OFF_SQ_RING:
|
||||
case IORING_OFF_CQ_RING:
|
||||
return io_uring_mmap_pages(ctx, vma, ctx->ring_pages,
|
||||
ctx->n_ring_pages);
|
||||
case IORING_OFF_SQES:
|
||||
return io_uring_mmap_pages(ctx, vma, ctx->sqe_pages,
|
||||
ctx->n_sqe_pages);
|
||||
case IORING_OFF_PBUF_RING:
|
||||
return io_pbuf_mmap(file, vma);
|
||||
}
|
||||
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
unsigned long io_uring_get_unmapped_area(struct file *filp, unsigned long addr,
|
||||
unsigned long len, unsigned long pgoff,
|
||||
unsigned long flags)
|
||||
{
|
||||
void *ptr;
|
||||
|
||||
/*
|
||||
* Do not allow to map to user-provided address to avoid breaking the
|
||||
* aliasing rules. Userspace is not able to guess the offset address of
|
||||
* kernel kmalloc()ed memory area.
|
||||
*/
|
||||
if (addr)
|
||||
return -EINVAL;
|
||||
|
||||
ptr = io_uring_validate_mmap_request(filp, pgoff, len);
|
||||
if (IS_ERR(ptr))
|
||||
return -ENOMEM;
|
||||
|
||||
/*
|
||||
* Some architectures have strong cache aliasing requirements.
|
||||
* For such architectures we need a coherent mapping which aliases
|
||||
* kernel memory *and* userspace memory. To achieve that:
|
||||
* - use a NULL file pointer to reference physical memory, and
|
||||
* - use the kernel virtual address of the shared io_uring context
|
||||
* (instead of the userspace-provided address, which has to be 0UL
|
||||
* anyway).
|
||||
* - use the same pgoff which the get_unmapped_area() uses to
|
||||
* calculate the page colouring.
|
||||
* For architectures without such aliasing requirements, the
|
||||
* architecture will return any suitable mapping because addr is 0.
|
||||
*/
|
||||
filp = NULL;
|
||||
flags |= MAP_SHARED;
|
||||
pgoff = 0; /* has been translated to ptr above */
|
||||
#ifdef SHM_COLOUR
|
||||
addr = (uintptr_t) ptr;
|
||||
pgoff = addr >> PAGE_SHIFT;
|
||||
#else
|
||||
addr = 0UL;
|
||||
#endif
|
||||
return current->mm->get_unmapped_area(filp, addr, len, pgoff, flags);
|
||||
}
|
||||
|
||||
#else /* !CONFIG_MMU */
|
||||
|
||||
int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
|
||||
{
|
||||
return is_nommu_shared_mapping(vma->vm_flags) ? 0 : -EINVAL;
|
||||
}
|
||||
|
||||
unsigned int io_uring_nommu_mmap_capabilities(struct file *file)
|
||||
{
|
||||
return NOMMU_MAP_DIRECT | NOMMU_MAP_READ | NOMMU_MAP_WRITE;
|
||||
}
|
||||
|
||||
unsigned long io_uring_get_unmapped_area(struct file *file, unsigned long addr,
|
||||
unsigned long len, unsigned long pgoff,
|
||||
unsigned long flags)
|
||||
{
|
||||
void *ptr;
|
||||
|
||||
ptr = io_uring_validate_mmap_request(file, pgoff, len);
|
||||
if (IS_ERR(ptr))
|
||||
return PTR_ERR(ptr);
|
||||
|
||||
return (unsigned long) ptr;
|
||||
}
|
||||
|
||||
#endif /* !CONFIG_MMU */
|
25
io_uring/memmap.h
Normal file
25
io_uring/memmap.h
Normal file
@ -0,0 +1,25 @@
|
||||
#ifndef IO_URING_MEMMAP_H
|
||||
#define IO_URING_MEMMAP_H
|
||||
|
||||
struct page **io_pin_pages(unsigned long ubuf, unsigned long len, int *npages);
|
||||
void io_pages_free(struct page ***pages, int npages);
|
||||
int io_uring_mmap_pages(struct io_ring_ctx *ctx, struct vm_area_struct *vma,
|
||||
struct page **pages, int npages);
|
||||
|
||||
void *io_pages_map(struct page ***out_pages, unsigned short *npages,
|
||||
size_t size);
|
||||
void io_pages_unmap(void *ptr, struct page ***pages, unsigned short *npages,
|
||||
bool put_pages);
|
||||
|
||||
void *__io_uaddr_map(struct page ***pages, unsigned short *npages,
|
||||
unsigned long uaddr, size_t size);
|
||||
|
||||
#ifndef CONFIG_MMU
|
||||
unsigned int io_uring_nommu_mmap_capabilities(struct file *file);
|
||||
#endif
|
||||
unsigned long io_uring_get_unmapped_area(struct file *file, unsigned long addr,
|
||||
unsigned long len, unsigned long pgoff,
|
||||
unsigned long flags);
|
||||
int io_uring_mmap(struct file *file, struct vm_area_struct *vma);
|
||||
|
||||
#endif
|
@ -16,6 +16,7 @@
|
||||
#include "alloc_cache.h"
|
||||
#include "openclose.h"
|
||||
#include "rsrc.h"
|
||||
#include "memmap.h"
|
||||
|
||||
struct io_rsrc_update {
|
||||
struct file *file;
|
||||
|
Loading…
Reference in New Issue
Block a user