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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /arch/powerpc/kexec/file_load_64.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/powerpc/kexec/file_load_64.c')
-rw-r--r-- | arch/powerpc/kexec/file_load_64.c | 1354 |
1 files changed, 1354 insertions, 0 deletions
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c new file mode 100644 index 0000000000..a3de5369d2 --- /dev/null +++ b/arch/powerpc/kexec/file_load_64.c @@ -0,0 +1,1354 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * ppc64 code to implement the kexec_file_load syscall + * + * Copyright (C) 2004 Adam Litke (agl@us.ibm.com) + * Copyright (C) 2004 IBM Corp. + * Copyright (C) 2004,2005 Milton D Miller II, IBM Corporation + * Copyright (C) 2005 R Sharada (sharada@in.ibm.com) + * Copyright (C) 2006 Mohan Kumar M (mohan@in.ibm.com) + * Copyright (C) 2020 IBM Corporation + * + * Based on kexec-tools' kexec-ppc64.c, kexec-elf-rel-ppc64.c, fs2dt.c. + * Heavily modified for the kernel by + * Hari Bathini, IBM Corporation. + */ + +#include <linux/kexec.h> +#include <linux/of_fdt.h> +#include <linux/libfdt.h> +#include <linux/of.h> +#include <linux/memblock.h> +#include <linux/slab.h> +#include <linux/vmalloc.h> +#include <asm/setup.h> +#include <asm/drmem.h> +#include <asm/firmware.h> +#include <asm/kexec_ranges.h> +#include <asm/crashdump-ppc64.h> +#include <asm/mmzone.h> +#include <asm/iommu.h> +#include <asm/prom.h> +#include <asm/plpks.h> + +struct umem_info { + u64 *buf; /* data buffer for usable-memory property */ + u32 size; /* size allocated for the data buffer */ + u32 max_entries; /* maximum no. of entries */ + u32 idx; /* index of current entry */ + + /* usable memory ranges to look up */ + unsigned int nr_ranges; + const struct range *ranges; +}; + +const struct kexec_file_ops * const kexec_file_loaders[] = { + &kexec_elf64_ops, + NULL +}; + +/** + * get_exclude_memory_ranges - Get exclude memory ranges. This list includes + * regions like opal/rtas, tce-table, initrd, + * kernel, htab which should be avoided while + * setting up kexec load segments. + * @mem_ranges: Range list to add the memory ranges to. + * + * Returns 0 on success, negative errno on error. + */ +static int get_exclude_memory_ranges(struct crash_mem **mem_ranges) +{ + int ret; + + ret = add_tce_mem_ranges(mem_ranges); + if (ret) + goto out; + + ret = add_initrd_mem_range(mem_ranges); + if (ret) + goto out; + + ret = add_htab_mem_range(mem_ranges); + if (ret) + goto out; + + ret = add_kernel_mem_range(mem_ranges); + if (ret) + goto out; + + ret = add_rtas_mem_range(mem_ranges); + if (ret) + goto out; + + ret = add_opal_mem_range(mem_ranges); + if (ret) + goto out; + + ret = add_reserved_mem_ranges(mem_ranges); + if (ret) + goto out; + + /* exclude memory ranges should be sorted for easy lookup */ + sort_memory_ranges(*mem_ranges, true); +out: + if (ret) + pr_err("Failed to setup exclude memory ranges\n"); + return ret; +} + +/** + * get_usable_memory_ranges - Get usable memory ranges. This list includes + * regions like crashkernel, opal/rtas & tce-table, + * that kdump kernel could use. + * @mem_ranges: Range list to add the memory ranges to. + * + * Returns 0 on success, negative errno on error. + */ +static int get_usable_memory_ranges(struct crash_mem **mem_ranges) +{ + int ret; + + /* + * Early boot failure observed on guests when low memory (first memory + * block?) is not added to usable memory. So, add [0, crashk_res.end] + * instead of [crashk_res.start, crashk_res.end] to workaround it. + * Also, crashed kernel's memory must be added to reserve map to + * avoid kdump kernel from using it. + */ + ret = add_mem_range(mem_ranges, 0, crashk_res.end + 1); + if (ret) + goto out; + + ret = add_rtas_mem_range(mem_ranges); + if (ret) + goto out; + + ret = add_opal_mem_range(mem_ranges); + if (ret) + goto out; + + ret = add_tce_mem_ranges(mem_ranges); +out: + if (ret) + pr_err("Failed to setup usable memory ranges\n"); + return ret; +} + +/** + * get_crash_memory_ranges - Get crash memory ranges. This list includes + * first/crashing kernel's memory regions that + * would be exported via an elfcore. + * @mem_ranges: Range list to add the memory ranges to. + * + * Returns 0 on success, negative errno on error. + */ +static int get_crash_memory_ranges(struct crash_mem **mem_ranges) +{ + phys_addr_t base, end; + struct crash_mem *tmem; + u64 i; + int ret; + + for_each_mem_range(i, &base, &end) { + u64 size = end - base; + + /* Skip backup memory region, which needs a separate entry */ + if (base == BACKUP_SRC_START) { + if (size > BACKUP_SRC_SIZE) { + base = BACKUP_SRC_END + 1; + size -= BACKUP_SRC_SIZE; + } else + continue; + } + + ret = add_mem_range(mem_ranges, base, size); + if (ret) + goto out; + + /* Try merging adjacent ranges before reallocation attempt */ + if ((*mem_ranges)->nr_ranges == (*mem_ranges)->max_nr_ranges) + sort_memory_ranges(*mem_ranges, true); + } + + /* Reallocate memory ranges if there is no space to split ranges */ + tmem = *mem_ranges; + if (tmem && (tmem->nr_ranges == tmem->max_nr_ranges)) { + tmem = realloc_mem_ranges(mem_ranges); + if (!tmem) + goto out; + } + + /* Exclude crashkernel region */ + ret = crash_exclude_mem_range(tmem, crashk_res.start, crashk_res.end); + if (ret) + goto out; + + /* + * FIXME: For now, stay in parity with kexec-tools but if RTAS/OPAL + * regions are exported to save their context at the time of + * crash, they should actually be backed up just like the + * first 64K bytes of memory. + */ + ret = add_rtas_mem_range(mem_ranges); + if (ret) + goto out; + + ret = add_opal_mem_range(mem_ranges); + if (ret) + goto out; + + /* create a separate program header for the backup region */ + ret = add_mem_range(mem_ranges, BACKUP_SRC_START, BACKUP_SRC_SIZE); + if (ret) + goto out; + + sort_memory_ranges(*mem_ranges, false); +out: + if (ret) + pr_err("Failed to setup crash memory ranges\n"); + return ret; +} + +/** + * get_reserved_memory_ranges - Get reserve memory ranges. This list includes + * memory regions that should be added to the + * memory reserve map to ensure the region is + * protected from any mischief. + * @mem_ranges: Range list to add the memory ranges to. + * + * Returns 0 on success, negative errno on error. + */ +static int get_reserved_memory_ranges(struct crash_mem **mem_ranges) +{ + int ret; + + ret = add_rtas_mem_range(mem_ranges); + if (ret) + goto out; + + ret = add_tce_mem_ranges(mem_ranges); + if (ret) + goto out; + + ret = add_reserved_mem_ranges(mem_ranges); +out: + if (ret) + pr_err("Failed to setup reserved memory ranges\n"); + return ret; +} + +/** + * __locate_mem_hole_top_down - Looks top down for a large enough memory hole + * in the memory regions between buf_min & buf_max + * for the buffer. If found, sets kbuf->mem. + * @kbuf: Buffer contents and memory parameters. + * @buf_min: Minimum address for the buffer. + * @buf_max: Maximum address for the buffer. + * + * Returns 0 on success, negative errno on error. + */ +static int __locate_mem_hole_top_down(struct kexec_buf *kbuf, + u64 buf_min, u64 buf_max) +{ + int ret = -EADDRNOTAVAIL; + phys_addr_t start, end; + u64 i; + + for_each_mem_range_rev(i, &start, &end) { + /* + * memblock uses [start, end) convention while it is + * [start, end] here. Fix the off-by-one to have the + * same convention. + */ + end -= 1; + + if (start > buf_max) + continue; + + /* Memory hole not found */ + if (end < buf_min) + break; + + /* Adjust memory region based on the given range */ + if (start < buf_min) + start = buf_min; + if (end > buf_max) + end = buf_max; + + start = ALIGN(start, kbuf->buf_align); + if (start < end && (end - start + 1) >= kbuf->memsz) { + /* Suitable memory range found. Set kbuf->mem */ + kbuf->mem = ALIGN_DOWN(end - kbuf->memsz + 1, + kbuf->buf_align); + ret = 0; + break; + } + } + + return ret; +} + +/** + * locate_mem_hole_top_down_ppc64 - Skip special memory regions to find a + * suitable buffer with top down approach. + * @kbuf: Buffer contents and memory parameters. + * @buf_min: Minimum address for the buffer. + * @buf_max: Maximum address for the buffer. + * @emem: Exclude memory ranges. + * + * Returns 0 on success, negative errno on error. + */ +static int locate_mem_hole_top_down_ppc64(struct kexec_buf *kbuf, + u64 buf_min, u64 buf_max, + const struct crash_mem *emem) +{ + int i, ret = 0, err = -EADDRNOTAVAIL; + u64 start, end, tmin, tmax; + + tmax = buf_max; + for (i = (emem->nr_ranges - 1); i >= 0; i--) { + start = emem->ranges[i].start; + end = emem->ranges[i].end; + + if (start > tmax) + continue; + + if (end < tmax) { + tmin = (end < buf_min ? buf_min : end + 1); + ret = __locate_mem_hole_top_down(kbuf, tmin, tmax); + if (!ret) + return 0; + } + + tmax = start - 1; + + if (tmax < buf_min) { + ret = err; + break; + } + ret = 0; + } + + if (!ret) { + tmin = buf_min; + ret = __locate_mem_hole_top_down(kbuf, tmin, tmax); + } + return ret; +} + +/** + * __locate_mem_hole_bottom_up - Looks bottom up for a large enough memory hole + * in the memory regions between buf_min & buf_max + * for the buffer. If found, sets kbuf->mem. + * @kbuf: Buffer contents and memory parameters. + * @buf_min: Minimum address for the buffer. + * @buf_max: Maximum address for the buffer. + * + * Returns 0 on success, negative errno on error. + */ +static int __locate_mem_hole_bottom_up(struct kexec_buf *kbuf, + u64 buf_min, u64 buf_max) +{ + int ret = -EADDRNOTAVAIL; + phys_addr_t start, end; + u64 i; + + for_each_mem_range(i, &start, &end) { + /* + * memblock uses [start, end) convention while it is + * [start, end] here. Fix the off-by-one to have the + * same convention. + */ + end -= 1; + + if (end < buf_min) + continue; + + /* Memory hole not found */ + if (start > buf_max) + break; + + /* Adjust memory region based on the given range */ + if (start < buf_min) + start = buf_min; + if (end > buf_max) + end = buf_max; + + start = ALIGN(start, kbuf->buf_align); + if (start < end && (end - start + 1) >= kbuf->memsz) { + /* Suitable memory range found. Set kbuf->mem */ + kbuf->mem = start; + ret = 0; + break; + } + } + + return ret; +} + +/** + * locate_mem_hole_bottom_up_ppc64 - Skip special memory regions to find a + * suitable buffer with bottom up approach. + * @kbuf: Buffer contents and memory parameters. + * @buf_min: Minimum address for the buffer. + * @buf_max: Maximum address for the buffer. + * @emem: Exclude memory ranges. + * + * Returns 0 on success, negative errno on error. + */ +static int locate_mem_hole_bottom_up_ppc64(struct kexec_buf *kbuf, + u64 buf_min, u64 buf_max, + const struct crash_mem *emem) +{ + int i, ret = 0, err = -EADDRNOTAVAIL; + u64 start, end, tmin, tmax; + + tmin = buf_min; + for (i = 0; i < emem->nr_ranges; i++) { + start = emem->ranges[i].start; + end = emem->ranges[i].end; + + if (end < tmin) + continue; + + if (start > tmin) { + tmax = (start > buf_max ? buf_max : start - 1); + ret = __locate_mem_hole_bottom_up(kbuf, tmin, tmax); + if (!ret) + return 0; + } + + tmin = end + 1; + + if (tmin > buf_max) { + ret = err; + break; + } + ret = 0; + } + + if (!ret) { + tmax = buf_max; + ret = __locate_mem_hole_bottom_up(kbuf, tmin, tmax); + } + return ret; +} + +/** + * check_realloc_usable_mem - Reallocate buffer if it can't accommodate entries + * @um_info: Usable memory buffer and ranges info. + * @cnt: No. of entries to accommodate. + * + * Frees up the old buffer if memory reallocation fails. + * + * Returns buffer on success, NULL on error. + */ +static u64 *check_realloc_usable_mem(struct umem_info *um_info, int cnt) +{ + u32 new_size; + u64 *tbuf; + + if ((um_info->idx + cnt) <= um_info->max_entries) + return um_info->buf; + + new_size = um_info->size + MEM_RANGE_CHUNK_SZ; + tbuf = krealloc(um_info->buf, new_size, GFP_KERNEL); + if (tbuf) { + um_info->buf = tbuf; + um_info->size = new_size; + um_info->max_entries = (um_info->size / sizeof(u64)); + } + + return tbuf; +} + +/** + * add_usable_mem - Add the usable memory ranges within the given memory range + * to the buffer + * @um_info: Usable memory buffer and ranges info. + * @base: Base address of memory range to look for. + * @end: End address of memory range to look for. + * + * Returns 0 on success, negative errno on error. + */ +static int add_usable_mem(struct umem_info *um_info, u64 base, u64 end) +{ + u64 loc_base, loc_end; + bool add; + int i; + + for (i = 0; i < um_info->nr_ranges; i++) { + add = false; + loc_base = um_info->ranges[i].start; + loc_end = um_info->ranges[i].end; + if (loc_base >= base && loc_end <= end) + add = true; + else if (base < loc_end && end > loc_base) { + if (loc_base < base) + loc_base = base; + if (loc_end > end) + loc_end = end; + add = true; + } + + if (add) { + if (!check_realloc_usable_mem(um_info, 2)) + return -ENOMEM; + + um_info->buf[um_info->idx++] = cpu_to_be64(loc_base); + um_info->buf[um_info->idx++] = + cpu_to_be64(loc_end - loc_base + 1); + } + } + + return 0; +} + +/** + * kdump_setup_usable_lmb - This is a callback function that gets called by + * walk_drmem_lmbs for every LMB to set its + * usable memory ranges. + * @lmb: LMB info. + * @usm: linux,drconf-usable-memory property value. + * @data: Pointer to usable memory buffer and ranges info. + * + * Returns 0 on success, negative errno on error. + */ +static int kdump_setup_usable_lmb(struct drmem_lmb *lmb, const __be32 **usm, + void *data) +{ + struct umem_info *um_info; + int tmp_idx, ret; + u64 base, end; + + /* + * kdump load isn't supported on kernels already booted with + * linux,drconf-usable-memory property. + */ + if (*usm) { + pr_err("linux,drconf-usable-memory property already exists!"); + return -EINVAL; + } + + um_info = data; + tmp_idx = um_info->idx; + if (!check_realloc_usable_mem(um_info, 1)) + return -ENOMEM; + + um_info->idx++; + base = lmb->base_addr; + end = base + drmem_lmb_size() - 1; + ret = add_usable_mem(um_info, base, end); + if (!ret) { + /* + * Update the no. of ranges added. Two entries (base & size) + * for every range added. + */ + um_info->buf[tmp_idx] = + cpu_to_be64((um_info->idx - tmp_idx - 1) / 2); + } + + return ret; +} + +#define NODE_PATH_LEN 256 +/** + * add_usable_mem_property - Add usable memory property for the given + * memory node. + * @fdt: Flattened device tree for the kdump kernel. + * @dn: Memory node. + * @um_info: Usable memory buffer and ranges info. + * + * Returns 0 on success, negative errno on error. + */ +static int add_usable_mem_property(void *fdt, struct device_node *dn, + struct umem_info *um_info) +{ + int n_mem_addr_cells, n_mem_size_cells, node; + char path[NODE_PATH_LEN]; + int i, len, ranges, ret; + const __be32 *prop; + u64 base, end; + + of_node_get(dn); + + if (snprintf(path, NODE_PATH_LEN, "%pOF", dn) > (NODE_PATH_LEN - 1)) { + pr_err("Buffer (%d) too small for memory node: %pOF\n", + NODE_PATH_LEN, dn); + return -EOVERFLOW; + } + pr_debug("Memory node path: %s\n", path); + + /* Now that we know the path, find its offset in kdump kernel's fdt */ + node = fdt_path_offset(fdt, path); + if (node < 0) { + pr_err("Malformed device tree: error reading %s\n", path); + ret = -EINVAL; + goto out; + } + + /* Get the address & size cells */ + n_mem_addr_cells = of_n_addr_cells(dn); + n_mem_size_cells = of_n_size_cells(dn); + pr_debug("address cells: %d, size cells: %d\n", n_mem_addr_cells, + n_mem_size_cells); + + um_info->idx = 0; + if (!check_realloc_usable_mem(um_info, 2)) { + ret = -ENOMEM; + goto out; + } + + prop = of_get_property(dn, "reg", &len); + if (!prop || len <= 0) { + ret = 0; + goto out; + } + + /* + * "reg" property represents sequence of (addr,size) tuples + * each representing a memory range. + */ + ranges = (len >> 2) / (n_mem_addr_cells + n_mem_size_cells); + + for (i = 0; i < ranges; i++) { + base = of_read_number(prop, n_mem_addr_cells); + prop += n_mem_addr_cells; + end = base + of_read_number(prop, n_mem_size_cells) - 1; + prop += n_mem_size_cells; + + ret = add_usable_mem(um_info, base, end); + if (ret) + goto out; + } + + /* + * No kdump kernel usable memory found in this memory node. + * Write (0,0) tuple in linux,usable-memory property for + * this region to be ignored. + */ + if (um_info->idx == 0) { + um_info->buf[0] = 0; + um_info->buf[1] = 0; + um_info->idx = 2; + } + + ret = fdt_setprop(fdt, node, "linux,usable-memory", um_info->buf, + (um_info->idx * sizeof(u64))); + +out: + of_node_put(dn); + return ret; +} + + +/** + * update_usable_mem_fdt - Updates kdump kernel's fdt with linux,usable-memory + * and linux,drconf-usable-memory DT properties as + * appropriate to restrict its memory usage. + * @fdt: Flattened device tree for the kdump kernel. + * @usable_mem: Usable memory ranges for kdump kernel. + * + * Returns 0 on success, negative errno on error. + */ +static int update_usable_mem_fdt(void *fdt, struct crash_mem *usable_mem) +{ + struct umem_info um_info; + struct device_node *dn; + int node, ret = 0; + + if (!usable_mem) { + pr_err("Usable memory ranges for kdump kernel not found\n"); + return -ENOENT; + } + + node = fdt_path_offset(fdt, "/ibm,dynamic-reconfiguration-memory"); + if (node == -FDT_ERR_NOTFOUND) + pr_debug("No dynamic reconfiguration memory found\n"); + else if (node < 0) { + pr_err("Malformed device tree: error reading /ibm,dynamic-reconfiguration-memory.\n"); + return -EINVAL; + } + + um_info.buf = NULL; + um_info.size = 0; + um_info.max_entries = 0; + um_info.idx = 0; + /* Memory ranges to look up */ + um_info.ranges = &(usable_mem->ranges[0]); + um_info.nr_ranges = usable_mem->nr_ranges; + + dn = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory"); + if (dn) { + ret = walk_drmem_lmbs(dn, &um_info, kdump_setup_usable_lmb); + of_node_put(dn); + + if (ret) { + pr_err("Could not setup linux,drconf-usable-memory property for kdump\n"); + goto out; + } + + ret = fdt_setprop(fdt, node, "linux,drconf-usable-memory", + um_info.buf, (um_info.idx * sizeof(u64))); + if (ret) { + pr_err("Failed to update fdt with linux,drconf-usable-memory property: %s", + fdt_strerror(ret)); + goto out; + } + } + + /* + * Walk through each memory node and set linux,usable-memory property + * for the corresponding node in kdump kernel's fdt. + */ + for_each_node_by_type(dn, "memory") { + ret = add_usable_mem_property(fdt, dn, &um_info); + if (ret) { + pr_err("Failed to set linux,usable-memory property for %s node", + dn->full_name); + of_node_put(dn); + goto out; + } + } + +out: + kfree(um_info.buf); + return ret; +} + +/** + * load_backup_segment - Locate a memory hole to place the backup region. + * @image: Kexec image. + * @kbuf: Buffer contents and memory parameters. + * + * Returns 0 on success, negative errno on error. + */ +static int load_backup_segment(struct kimage *image, struct kexec_buf *kbuf) +{ + void *buf; + int ret; + + /* + * Setup a source buffer for backup segment. + * + * A source buffer has no meaning for backup region as data will + * be copied from backup source, after crash, in the purgatory. + * But as load segment code doesn't recognize such segments, + * setup a dummy source buffer to keep it happy for now. + */ + buf = vzalloc(BACKUP_SRC_SIZE); + if (!buf) + return -ENOMEM; + + kbuf->buffer = buf; + kbuf->mem = KEXEC_BUF_MEM_UNKNOWN; + kbuf->bufsz = kbuf->memsz = BACKUP_SRC_SIZE; + kbuf->top_down = false; + + ret = kexec_add_buffer(kbuf); + if (ret) { + vfree(buf); + return ret; + } + + image->arch.backup_buf = buf; + image->arch.backup_start = kbuf->mem; + return 0; +} + +/** + * update_backup_region_phdr - Update backup region's offset for the core to + * export the region appropriately. + * @image: Kexec image. + * @ehdr: ELF core header. + * + * Assumes an exclusive program header is setup for the backup region + * in the ELF headers + * + * Returns nothing. + */ +static void update_backup_region_phdr(struct kimage *image, Elf64_Ehdr *ehdr) +{ + Elf64_Phdr *phdr; + unsigned int i; + + phdr = (Elf64_Phdr *)(ehdr + 1); + for (i = 0; i < ehdr->e_phnum; i++) { + if (phdr->p_paddr == BACKUP_SRC_START) { + phdr->p_offset = image->arch.backup_start; + pr_debug("Backup region offset updated to 0x%lx\n", + image->arch.backup_start); + return; + } + } +} + +/** + * load_elfcorehdr_segment - Setup crash memory ranges and initialize elfcorehdr + * segment needed to load kdump kernel. + * @image: Kexec image. + * @kbuf: Buffer contents and memory parameters. + * + * Returns 0 on success, negative errno on error. + */ +static int load_elfcorehdr_segment(struct kimage *image, struct kexec_buf *kbuf) +{ + struct crash_mem *cmem = NULL; + unsigned long headers_sz; + void *headers = NULL; + int ret; + + ret = get_crash_memory_ranges(&cmem); + if (ret) + goto out; + + /* Setup elfcorehdr segment */ + ret = crash_prepare_elf64_headers(cmem, false, &headers, &headers_sz); + if (ret) { + pr_err("Failed to prepare elf headers for the core\n"); + goto out; + } + + /* Fix the offset for backup region in the ELF header */ + update_backup_region_phdr(image, headers); + + kbuf->buffer = headers; + kbuf->mem = KEXEC_BUF_MEM_UNKNOWN; + kbuf->bufsz = kbuf->memsz = headers_sz; + kbuf->top_down = false; + + ret = kexec_add_buffer(kbuf); + if (ret) { + vfree(headers); + goto out; + } + + image->elf_load_addr = kbuf->mem; + image->elf_headers_sz = headers_sz; + image->elf_headers = headers; +out: + kfree(cmem); + return ret; +} + +/** + * load_crashdump_segments_ppc64 - Initialize the additional segements needed + * to load kdump kernel. + * @image: Kexec image. + * @kbuf: Buffer contents and memory parameters. + * + * Returns 0 on success, negative errno on error. + */ +int load_crashdump_segments_ppc64(struct kimage *image, + struct kexec_buf *kbuf) +{ + int ret; + + /* Load backup segment - first 64K bytes of the crashing kernel */ + ret = load_backup_segment(image, kbuf); + if (ret) { + pr_err("Failed to load backup segment\n"); + return ret; + } + pr_debug("Loaded the backup region at 0x%lx\n", kbuf->mem); + + /* Load elfcorehdr segment - to export crashing kernel's vmcore */ + ret = load_elfcorehdr_segment(image, kbuf); + if (ret) { + pr_err("Failed to load elfcorehdr segment\n"); + return ret; + } + pr_debug("Loaded elf core header at 0x%lx, bufsz=0x%lx memsz=0x%lx\n", + image->elf_load_addr, kbuf->bufsz, kbuf->memsz); + + return 0; +} + +/** + * setup_purgatory_ppc64 - initialize PPC64 specific purgatory's global + * variables and call setup_purgatory() to initialize + * common global variable. + * @image: kexec image. + * @slave_code: Slave code for the purgatory. + * @fdt: Flattened device tree for the next kernel. + * @kernel_load_addr: Address where the kernel is loaded. + * @fdt_load_addr: Address where the flattened device tree is loaded. + * + * Returns 0 on success, negative errno on error. + */ +int setup_purgatory_ppc64(struct kimage *image, const void *slave_code, + const void *fdt, unsigned long kernel_load_addr, + unsigned long fdt_load_addr) +{ + struct device_node *dn = NULL; + int ret; + + ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr, + fdt_load_addr); + if (ret) + goto out; + + if (image->type == KEXEC_TYPE_CRASH) { + u32 my_run_at_load = 1; + + /* + * Tell relocatable kernel to run at load address + * via the word meant for that at 0x5c. + */ + ret = kexec_purgatory_get_set_symbol(image, "run_at_load", + &my_run_at_load, + sizeof(my_run_at_load), + false); + if (ret) + goto out; + } + + /* Tell purgatory where to look for backup region */ + ret = kexec_purgatory_get_set_symbol(image, "backup_start", + &image->arch.backup_start, + sizeof(image->arch.backup_start), + false); + if (ret) + goto out; + + /* Setup OPAL base & entry values */ + dn = of_find_node_by_path("/ibm,opal"); + if (dn) { + u64 val; + + of_property_read_u64(dn, "opal-base-address", &val); + ret = kexec_purgatory_get_set_symbol(image, "opal_base", &val, + sizeof(val), false); + if (ret) + goto out; + + of_property_read_u64(dn, "opal-entry-address", &val); + ret = kexec_purgatory_get_set_symbol(image, "opal_entry", &val, + sizeof(val), false); + } +out: + if (ret) + pr_err("Failed to setup purgatory symbols"); + of_node_put(dn); + return ret; +} + +/** + * cpu_node_size - Compute the size of a CPU node in the FDT. + * This should be done only once and the value is stored in + * a static variable. + * Returns the max size of a CPU node in the FDT. + */ +static unsigned int cpu_node_size(void) +{ + static unsigned int size; + struct device_node *dn; + struct property *pp; + + /* + * Don't compute it twice, we are assuming that the per CPU node size + * doesn't change during the system's life. + */ + if (size) + return size; + + dn = of_find_node_by_type(NULL, "cpu"); + if (WARN_ON_ONCE(!dn)) { + // Unlikely to happen + return 0; + } + + /* + * We compute the sub node size for a CPU node, assuming it + * will be the same for all. + */ + size += strlen(dn->name) + 5; + for_each_property_of_node(dn, pp) { + size += strlen(pp->name); + size += pp->length; + } + + of_node_put(dn); + return size; +} + +/** + * kexec_extra_fdt_size_ppc64 - Return the estimated additional size needed to + * setup FDT for kexec/kdump kernel. + * @image: kexec image being loaded. + * + * Returns the estimated extra size needed for kexec/kdump kernel FDT. + */ +unsigned int kexec_extra_fdt_size_ppc64(struct kimage *image) +{ + unsigned int cpu_nodes, extra_size = 0; + struct device_node *dn; + u64 usm_entries; + + // Budget some space for the password blob. There's already extra space + // for the key name + if (plpks_is_available()) + extra_size += (unsigned int)plpks_get_passwordlen(); + + if (image->type != KEXEC_TYPE_CRASH) + return extra_size; + + /* + * For kdump kernel, account for linux,usable-memory and + * linux,drconf-usable-memory properties. Get an approximate on the + * number of usable memory entries and use for FDT size estimation. + */ + if (drmem_lmb_size()) { + usm_entries = ((memory_hotplug_max() / drmem_lmb_size()) + + (2 * (resource_size(&crashk_res) / drmem_lmb_size()))); + extra_size += (unsigned int)(usm_entries * sizeof(u64)); + } + + /* + * Get the number of CPU nodes in the current DT. This allows to + * reserve places for CPU nodes added since the boot time. + */ + cpu_nodes = 0; + for_each_node_by_type(dn, "cpu") { + cpu_nodes++; + } + + if (cpu_nodes > boot_cpu_node_count) + extra_size += (cpu_nodes - boot_cpu_node_count) * cpu_node_size(); + + return extra_size; +} + +/** + * add_node_props - Reads node properties from device node structure and add + * them to fdt. + * @fdt: Flattened device tree of the kernel + * @node_offset: offset of the node to add a property at + * @dn: device node pointer + * + * Returns 0 on success, negative errno on error. + */ +static int add_node_props(void *fdt, int node_offset, const struct device_node *dn) +{ + int ret = 0; + struct property *pp; + + if (!dn) + return -EINVAL; + + for_each_property_of_node(dn, pp) { + ret = fdt_setprop(fdt, node_offset, pp->name, pp->value, pp->length); + if (ret < 0) { + pr_err("Unable to add %s property: %s\n", pp->name, fdt_strerror(ret)); + return ret; + } + } + return ret; +} + +/** + * update_cpus_node - Update cpus node of flattened device tree using of_root + * device node. + * @fdt: Flattened device tree of the kernel. + * + * Returns 0 on success, negative errno on error. + */ +static int update_cpus_node(void *fdt) +{ + struct device_node *cpus_node, *dn; + int cpus_offset, cpus_subnode_offset, ret = 0; + + cpus_offset = fdt_path_offset(fdt, "/cpus"); + if (cpus_offset < 0 && cpus_offset != -FDT_ERR_NOTFOUND) { + pr_err("Malformed device tree: error reading /cpus node: %s\n", + fdt_strerror(cpus_offset)); + return cpus_offset; + } + + if (cpus_offset > 0) { + ret = fdt_del_node(fdt, cpus_offset); + if (ret < 0) { + pr_err("Error deleting /cpus node: %s\n", fdt_strerror(ret)); + return -EINVAL; + } + } + + /* Add cpus node to fdt */ + cpus_offset = fdt_add_subnode(fdt, fdt_path_offset(fdt, "/"), "cpus"); + if (cpus_offset < 0) { + pr_err("Error creating /cpus node: %s\n", fdt_strerror(cpus_offset)); + return -EINVAL; + } + + /* Add cpus node properties */ + cpus_node = of_find_node_by_path("/cpus"); + ret = add_node_props(fdt, cpus_offset, cpus_node); + of_node_put(cpus_node); + if (ret < 0) + return ret; + + /* Loop through all subnodes of cpus and add them to fdt */ + for_each_node_by_type(dn, "cpu") { + cpus_subnode_offset = fdt_add_subnode(fdt, cpus_offset, dn->full_name); + if (cpus_subnode_offset < 0) { + pr_err("Unable to add %s subnode: %s\n", dn->full_name, + fdt_strerror(cpus_subnode_offset)); + ret = cpus_subnode_offset; + goto out; + } + + ret = add_node_props(fdt, cpus_subnode_offset, dn); + if (ret < 0) + goto out; + } +out: + of_node_put(dn); + return ret; +} + +static int copy_property(void *fdt, int node_offset, const struct device_node *dn, + const char *propname) +{ + const void *prop, *fdtprop; + int len = 0, fdtlen = 0; + + prop = of_get_property(dn, propname, &len); + fdtprop = fdt_getprop(fdt, node_offset, propname, &fdtlen); + + if (fdtprop && !prop) + return fdt_delprop(fdt, node_offset, propname); + else if (prop) + return fdt_setprop(fdt, node_offset, propname, prop, len); + else + return -FDT_ERR_NOTFOUND; +} + +static int update_pci_dma_nodes(void *fdt, const char *dmapropname) +{ + struct device_node *dn; + int pci_offset, root_offset, ret = 0; + + if (!firmware_has_feature(FW_FEATURE_LPAR)) + return 0; + + root_offset = fdt_path_offset(fdt, "/"); + for_each_node_with_property(dn, dmapropname) { + pci_offset = fdt_subnode_offset(fdt, root_offset, of_node_full_name(dn)); + if (pci_offset < 0) + continue; + + ret = copy_property(fdt, pci_offset, dn, "ibm,dma-window"); + if (ret < 0) + break; + ret = copy_property(fdt, pci_offset, dn, dmapropname); + if (ret < 0) + break; + } + + return ret; +} + +/** + * setup_new_fdt_ppc64 - Update the flattend device-tree of the kernel + * being loaded. + * @image: kexec image being loaded. + * @fdt: Flattened device tree for the next kernel. + * @initrd_load_addr: Address where the next initrd will be loaded. + * @initrd_len: Size of the next initrd, or 0 if there will be none. + * @cmdline: Command line for the next kernel, or NULL if there will + * be none. + * + * Returns 0 on success, negative errno on error. + */ +int setup_new_fdt_ppc64(const struct kimage *image, void *fdt, + unsigned long initrd_load_addr, + unsigned long initrd_len, const char *cmdline) +{ + struct crash_mem *umem = NULL, *rmem = NULL; + int i, nr_ranges, ret; + + /* + * Restrict memory usage for kdump kernel by setting up + * usable memory ranges and memory reserve map. + */ + if (image->type == KEXEC_TYPE_CRASH) { + ret = get_usable_memory_ranges(&umem); + if (ret) + goto out; + + ret = update_usable_mem_fdt(fdt, umem); + if (ret) { + pr_err("Error setting up usable-memory property for kdump kernel\n"); + goto out; + } + + /* + * Ensure we don't touch crashed kernel's memory except the + * first 64K of RAM, which will be backed up. + */ + ret = fdt_add_mem_rsv(fdt, BACKUP_SRC_END + 1, + crashk_res.start - BACKUP_SRC_SIZE); + if (ret) { + pr_err("Error reserving crash memory: %s\n", + fdt_strerror(ret)); + goto out; + } + + /* Ensure backup region is not used by kdump/capture kernel */ + ret = fdt_add_mem_rsv(fdt, image->arch.backup_start, + BACKUP_SRC_SIZE); + if (ret) { + pr_err("Error reserving memory for backup: %s\n", + fdt_strerror(ret)); + goto out; + } + } + + /* Update cpus nodes information to account hotplug CPUs. */ + ret = update_cpus_node(fdt); + if (ret < 0) + goto out; + + ret = update_pci_dma_nodes(fdt, DIRECT64_PROPNAME); + if (ret < 0) + goto out; + + ret = update_pci_dma_nodes(fdt, DMA64_PROPNAME); + if (ret < 0) + goto out; + + /* Update memory reserve map */ + ret = get_reserved_memory_ranges(&rmem); + if (ret) + goto out; + + nr_ranges = rmem ? rmem->nr_ranges : 0; + for (i = 0; i < nr_ranges; i++) { + u64 base, size; + + base = rmem->ranges[i].start; + size = rmem->ranges[i].end - base + 1; + ret = fdt_add_mem_rsv(fdt, base, size); + if (ret) { + pr_err("Error updating memory reserve map: %s\n", + fdt_strerror(ret)); + goto out; + } + } + + // If we have PLPKS active, we need to provide the password to the new kernel + if (plpks_is_available()) + ret = plpks_populate_fdt(fdt); + +out: + kfree(rmem); + kfree(umem); + return ret; +} + +/** + * arch_kexec_locate_mem_hole - Skip special memory regions like rtas, opal, + * tce-table, reserved-ranges & such (exclude + * memory ranges) as they can't be used for kexec + * segment buffer. Sets kbuf->mem when a suitable + * memory hole is found. + * @kbuf: Buffer contents and memory parameters. + * + * Assumes minimum of PAGE_SIZE alignment for kbuf->memsz & kbuf->buf_align. + * + * Returns 0 on success, negative errno on error. + */ +int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf) +{ + struct crash_mem **emem; + u64 buf_min, buf_max; + int ret; + + /* Look up the exclude ranges list while locating the memory hole */ + emem = &(kbuf->image->arch.exclude_ranges); + if (!(*emem) || ((*emem)->nr_ranges == 0)) { + pr_warn("No exclude range list. Using the default locate mem hole method\n"); + return kexec_locate_mem_hole(kbuf); + } + + buf_min = kbuf->buf_min; + buf_max = kbuf->buf_max; + /* Segments for kdump kernel should be within crashkernel region */ + if (kbuf->image->type == KEXEC_TYPE_CRASH) { + buf_min = (buf_min < crashk_res.start ? + crashk_res.start : buf_min); + buf_max = (buf_max > crashk_res.end ? + crashk_res.end : buf_max); + } + + if (buf_min > buf_max) { + pr_err("Invalid buffer min and/or max values\n"); + return -EINVAL; + } + + if (kbuf->top_down) + ret = locate_mem_hole_top_down_ppc64(kbuf, buf_min, buf_max, + *emem); + else + ret = locate_mem_hole_bottom_up_ppc64(kbuf, buf_min, buf_max, + *emem); + + /* Add the buffer allocated to the exclude list for the next lookup */ + if (!ret) { + add_mem_range(emem, kbuf->mem, kbuf->memsz); + sort_memory_ranges(*emem, true); + } else { + pr_err("Failed to locate memory buffer of size %lu\n", + kbuf->memsz); + } + return ret; +} + +/** + * arch_kexec_kernel_image_probe - Does additional handling needed to setup + * kexec segments. + * @image: kexec image being loaded. + * @buf: Buffer pointing to elf data. + * @buf_len: Length of the buffer. + * + * Returns 0 on success, negative errno on error. + */ +int arch_kexec_kernel_image_probe(struct kimage *image, void *buf, + unsigned long buf_len) +{ + int ret; + + /* Get exclude memory ranges needed for setting up kexec segments */ + ret = get_exclude_memory_ranges(&(image->arch.exclude_ranges)); + if (ret) { + pr_err("Failed to setup exclude memory ranges for buffer lookup\n"); + return ret; + } + + return kexec_image_probe_default(image, buf, buf_len); +} + +/** + * arch_kimage_file_post_load_cleanup - Frees up all the allocations done + * while loading the image. + * @image: kexec image being loaded. + * + * Returns 0 on success, negative errno on error. + */ +int arch_kimage_file_post_load_cleanup(struct kimage *image) +{ + kfree(image->arch.exclude_ranges); + image->arch.exclude_ranges = NULL; + + vfree(image->arch.backup_buf); + image->arch.backup_buf = NULL; + + vfree(image->elf_headers); + image->elf_headers = NULL; + image->elf_headers_sz = 0; + + kvfree(image->arch.fdt); + image->arch.fdt = NULL; + + return kexec_image_post_load_cleanup_default(image); +} |