diff options
Diffstat (limited to 'kernel/kexec_file.c')
| -rw-r--r-- | kernel/kexec_file.c | 61 |
1 files changed, 55 insertions, 6 deletions
diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index 69fe76fd9233..91d46502a817 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -26,6 +26,7 @@ #include <linux/kernel_read_file.h> #include <linux/syscalls.h> #include <linux/vmalloc.h> +#include <linux/dma-map-ops.h> #include "kexec_internal.h" #ifdef CONFIG_KEXEC_SIG @@ -253,6 +254,8 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, ret = 0; } + image->no_cma = !!(flags & KEXEC_FILE_NO_CMA); + if (cmdline_len) { image->cmdline_buf = memdup_user(cmdline_ptr, cmdline_len); if (IS_ERR(image->cmdline_buf)) { @@ -434,7 +437,7 @@ SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd, i, ksegment->buf, ksegment->bufsz, ksegment->mem, ksegment->memsz); - ret = kimage_load_segment(image, &image->segment[i]); + ret = kimage_load_segment(image, i); if (ret) goto out; } @@ -663,6 +666,43 @@ static int kexec_walk_resources(struct kexec_buf *kbuf, return walk_system_ram_res(0, ULONG_MAX, kbuf, func); } +static int kexec_alloc_contig(struct kexec_buf *kbuf) +{ + size_t nr_pages = kbuf->memsz >> PAGE_SHIFT; + unsigned long mem; + struct page *p; + + /* User space disabled CMA allocations, bail out. */ + if (kbuf->image->no_cma) + return -EPERM; + + /* Skip CMA logic for crash kernel */ + if (kbuf->image->type == KEXEC_TYPE_CRASH) + return -EPERM; + + p = dma_alloc_from_contiguous(NULL, nr_pages, get_order(kbuf->buf_align), true); + if (!p) + return -ENOMEM; + + pr_debug("allocated %zu DMA pages at 0x%lx", nr_pages, page_to_boot_pfn(p)); + + mem = page_to_boot_pfn(p) << PAGE_SHIFT; + + if (kimage_is_destination_range(kbuf->image, mem, mem + kbuf->memsz)) { + /* Our region is already in use by a statically defined one. Bail out. */ + pr_debug("CMA overlaps existing mem: 0x%lx+0x%lx\n", mem, kbuf->memsz); + dma_release_from_contiguous(NULL, p, nr_pages); + return -EBUSY; + } + + kbuf->mem = page_to_boot_pfn(p) << PAGE_SHIFT; + kbuf->cma = p; + + arch_kexec_post_alloc_pages(page_address(p), (int)nr_pages, 0); + + return 0; +} + /** * kexec_locate_mem_hole - find free memory for the purgatory or the next kernel * @kbuf: Parameters for the memory search. @@ -687,6 +727,13 @@ int kexec_locate_mem_hole(struct kexec_buf *kbuf) if (ret <= 0) return ret; + /* + * Try to find a free physically contiguous block of memory first. With that, we + * can avoid any copying at kexec time. + */ + if (!kexec_alloc_contig(kbuf)) + return 0; + if (!IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK)) ret = kexec_walk_resources(kbuf, locate_mem_hole_callback); else @@ -732,6 +779,7 @@ int kexec_add_buffer(struct kexec_buf *kbuf) /* Ensure minimum alignment needed for segments. */ kbuf->memsz = ALIGN(kbuf->memsz, PAGE_SIZE); kbuf->buf_align = max(kbuf->buf_align, PAGE_SIZE); + kbuf->cma = NULL; /* Walk the RAM ranges and allocate a suitable range for the buffer */ ret = arch_kexec_locate_mem_hole(kbuf); @@ -744,6 +792,7 @@ int kexec_add_buffer(struct kexec_buf *kbuf) ksegment->bufsz = kbuf->bufsz; ksegment->mem = kbuf->mem; ksegment->memsz = kbuf->memsz; + kbuf->image->segment_cma[kbuf->image->nr_segments] = kbuf->cma; kbuf->image->nr_segments++; return 0; } @@ -751,7 +800,7 @@ int kexec_add_buffer(struct kexec_buf *kbuf) /* Calculate and store the digest of segments */ static int kexec_calculate_store_digests(struct kimage *image) { - struct sha256_state state; + struct sha256_ctx sctx; int ret = 0, i, j, zero_buf_sz, sha_region_sz; size_t nullsz; u8 digest[SHA256_DIGEST_SIZE]; @@ -770,7 +819,7 @@ static int kexec_calculate_store_digests(struct kimage *image) if (!sha_regions) return -ENOMEM; - sha256_init(&state); + sha256_init(&sctx); for (j = i = 0; i < image->nr_segments; i++) { struct kexec_segment *ksegment; @@ -796,7 +845,7 @@ static int kexec_calculate_store_digests(struct kimage *image) if (check_ima_segment_index(image, i)) continue; - sha256_update(&state, ksegment->kbuf, ksegment->bufsz); + sha256_update(&sctx, ksegment->kbuf, ksegment->bufsz); /* * Assume rest of the buffer is filled with zero and @@ -808,7 +857,7 @@ static int kexec_calculate_store_digests(struct kimage *image) if (bytes > zero_buf_sz) bytes = zero_buf_sz; - sha256_update(&state, zero_buf, bytes); + sha256_update(&sctx, zero_buf, bytes); nullsz -= bytes; } @@ -817,7 +866,7 @@ static int kexec_calculate_store_digests(struct kimage *image) j++; } - sha256_final(&state, digest); + sha256_final(&sctx, digest); ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha_regions", sha_regions, sha_region_sz, 0); |