// 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include 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; ret = of_property_read_u64(dn, "opal-base-address", &val); if (ret) goto out; ret = kexec_purgatory_get_set_symbol(image, "opal_base", &val, sizeof(val), false); if (ret) goto out; ret = of_property_read_u64(dn, "opal-entry-address", &val); if (ret) goto out; 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); }