arch_kexec_walk_mem and arch_kexec_apply_relocations_add are used by generic kexec code, while setup_purgatory is powerpc-specific and sets runtime variables needed by the powerpc purgatory implementation.
Signed-off-by: Josh Sklar <sk...@linux.vnet.ibm.com> Signed-off-by: Thiago Jung Bauermann <bauer...@linux.vnet.ibm.com> --- arch/powerpc/Kconfig | 13 ++ arch/powerpc/include/asm/kexec.h | 7 + arch/powerpc/include/asm/systbl.h | 1 + arch/powerpc/include/asm/unistd.h | 2 +- arch/powerpc/include/uapi/asm/unistd.h | 1 + arch/powerpc/kernel/Makefile | 4 +- arch/powerpc/kernel/machine_kexec_64.c | 252 +++++++++++++++++++++++++++++++++ 7 files changed, 278 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 140a1b84019a..41300c3a1bfe 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -460,6 +460,19 @@ config KEXEC interface is strongly in flux, so no good recommendation can be made. +config KEXEC_FILE + bool "kexec file based system call" + select KEXEC_CORE + select BUILD_BIN2C + depends on PPC64 + depends on CRYPTO=y + depends on CRYPTO_SHA256=y + help + This is a new version of the kexec system call. This call is + file based and takes in file descriptors as system call arguments + for kernel and initramfs as opposed to a list of segments as is the + case for the older kexec call. + config RELOCATABLE bool "Build a relocatable kernel" depends on (PPC64 && !COMPILE_TEST) || (FLATMEM && (44x || FSL_BOOKE)) diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h index eca2f975bf44..0c7e020d935a 100644 --- a/arch/powerpc/include/asm/kexec.h +++ b/arch/powerpc/include/asm/kexec.h @@ -91,6 +91,13 @@ static inline bool kdump_in_progress(void) return crashing_cpu >= 0; } +#ifdef CONFIG_KEXEC_FILE +int setup_purgatory(struct kimage *image, const void *slave_code, + const void *fdt, unsigned long kernel_load_addr, + unsigned long fdt_load_addr, unsigned long stack_top, + int debug); +#endif /* CONFIG_KEXEC_FILE */ + #else /* !CONFIG_KEXEC_CORE */ static inline void crash_kexec_secondary(struct pt_regs *regs) { } diff --git a/arch/powerpc/include/asm/systbl.h b/arch/powerpc/include/asm/systbl.h index 2fc5d4db503c..4b369d83fe9c 100644 --- a/arch/powerpc/include/asm/systbl.h +++ b/arch/powerpc/include/asm/systbl.h @@ -386,3 +386,4 @@ SYSCALL(mlock2) SYSCALL(copy_file_range) COMPAT_SYS_SPU(preadv2) COMPAT_SYS_SPU(pwritev2) +SYSCALL(kexec_file_load) diff --git a/arch/powerpc/include/asm/unistd.h b/arch/powerpc/include/asm/unistd.h index cf12c580f6b2..a01e97d3f305 100644 --- a/arch/powerpc/include/asm/unistd.h +++ b/arch/powerpc/include/asm/unistd.h @@ -12,7 +12,7 @@ #include <uapi/asm/unistd.h> -#define NR_syscalls 382 +#define NR_syscalls 383 #define __NR__exit __NR_exit diff --git a/arch/powerpc/include/uapi/asm/unistd.h b/arch/powerpc/include/uapi/asm/unistd.h index e9f5f41aa55a..2f26335a3c42 100644 --- a/arch/powerpc/include/uapi/asm/unistd.h +++ b/arch/powerpc/include/uapi/asm/unistd.h @@ -392,5 +392,6 @@ #define __NR_copy_file_range 379 #define __NR_preadv2 380 #define __NR_pwritev2 381 +#define __NR_kexec_file_load 382 #endif /* _UAPI_ASM_POWERPC_UNISTD_H_ */ diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index fd6b7b96d93d..fef0d730acc4 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -123,9 +123,11 @@ ifneq ($(CONFIG_PPC_INDIRECT_PIO),y) obj-y += iomap.o endif -ifeq ($(CONFIG_MODULES)$(CONFIG_WORD_SIZE),y64) +ifneq ($(CONFIG_MODULES)$(CONFIG_KEXEC_FILE),) +ifeq ($(CONFIG_WORD_SIZE),64) obj-y += elf_util.o elf_util_64.o endif +endif obj64-$(CONFIG_PPC_TRANSACTIONAL_MEM) += tm.o diff --git a/arch/powerpc/kernel/machine_kexec_64.c b/arch/powerpc/kernel/machine_kexec_64.c index 4c780a342282..1e678dc5096a 100644 --- a/arch/powerpc/kernel/machine_kexec_64.c +++ b/arch/powerpc/kernel/machine_kexec_64.c @@ -18,6 +18,8 @@ #include <linux/kernel.h> #include <linux/cpu.h> #include <linux/hardirq.h> +#include <linux/memblock.h> +#include <linux/libfdt.h> #include <asm/page.h> #include <asm/current.h> @@ -31,6 +33,12 @@ #include <asm/hw_breakpoint.h> #include <asm/asm-prototypes.h> +#define SLAVE_CODE_SIZE 256 + +#ifdef CONFIG_KEXEC_FILE +static struct kexec_file_ops *kexec_file_loaders[] = { }; +#endif + #ifdef CONFIG_PPC_BOOK3E int default_machine_kexec_prepare(struct kimage *image) { @@ -432,3 +440,247 @@ static int __init export_htab_values(void) } late_initcall(export_htab_values); #endif /* CONFIG_PPC_STD_MMU_64 */ + +#ifdef CONFIG_KEXEC_FILE +int arch_kexec_kernel_image_probe(struct kimage *image, void *buf, + unsigned long buf_len) +{ + int i, ret = -ENOEXEC; + struct kexec_file_ops *fops; + + /* We don't support crash kernels yet. */ + if (image->type == KEXEC_TYPE_CRASH) + return -ENOTSUPP; + + for (i = 0; i < ARRAY_SIZE(kexec_file_loaders); i++) { + fops = kexec_file_loaders[i]; + if (!fops || !fops->probe) + continue; + + ret = fops->probe(buf, buf_len); + if (!ret) { + image->fops = fops; + return ret; + } + } + + return ret; +} + +void *arch_kexec_kernel_image_load(struct kimage *image) +{ + if (!image->fops || !image->fops->load) + return ERR_PTR(-ENOEXEC); + + return image->fops->load(image, image->kernel_buf, + image->kernel_buf_len, image->initrd_buf, + image->initrd_buf_len, image->cmdline_buf, + image->cmdline_buf_len); +} + +int arch_kimage_file_post_load_cleanup(struct kimage *image) +{ + if (!image->fops || !image->fops->cleanup) + return 0; + + return image->fops->cleanup(image->image_loader_data); +} + +/** + * arch_kexec_walk_mem() - call func(data) for each unreserved memory block + * @kbuf: Context info for the search. Also passed to @func. + * @func: Function to call for each memory block. + * + * This function is used by kexec_add_buffer and kexec_locate_mem_hole + * to find unreserved memory to load kexec segments into. + * + * Return: The memory walk will stop when func returns a non-zero value + * and that value will be returned. If all free regions are visited without + * func returning non-zero, then zero will be returned. + */ +int arch_kexec_walk_mem(struct kexec_buf *kbuf, int (*func)(u64, u64, void *)) +{ + int ret = 0; + u64 i; + phys_addr_t mstart, mend; + + if (kbuf->top_down) { + for_each_free_mem_range_reverse(i, NUMA_NO_NODE, 0, + &mstart, &mend, NULL) { + /* + * In memblock, end points to the first byte after the + * range while in kexec, end points to the last byte + * in the range. + */ + ret = func(mstart, mend - 1, kbuf); + if (ret) + break; + } + } else { + for_each_free_mem_range(i, NUMA_NO_NODE, 0, &mstart, &mend, + NULL) { + /* + * In memblock, end points to the first byte after the + * range while in kexec, end points to the last byte + * in the range. + */ + ret = func(mstart, mend - 1, kbuf); + if (ret) + break; + } + } + + return ret; +} + +/** + * arch_kexec_apply_relocations_add() - apply purgatory relocations + * @ehdr: Pointer to ELF headers. + * @sechdrs: Pointer to section headers. + * @relsec: Section index of SHT_RELA section. + * + * Elf64_Shdr.sh_offset has been modified to keep the pointer to the section + * contents, while Elf64_Shdr.sh_addr points to the final address of the + * section in memory. + */ +int arch_kexec_apply_relocations_add(const Elf64_Ehdr *ehdr, + Elf64_Shdr *sechdrs, unsigned int relsec) +{ + /* Section containing the relocation entries. */ + Elf64_Shdr *rel_section = &sechdrs[relsec]; + const Elf64_Rela *rela = (const Elf64_Rela *) rel_section->sh_offset; + unsigned int num_rela = rel_section->sh_size / sizeof(Elf64_Rela); + /* Section to which relocations apply. */ + Elf64_Shdr *target_section = &sechdrs[rel_section->sh_info]; + /* Associated symbol table. */ + Elf64_Shdr *symtabsec = &sechdrs[rel_section->sh_link]; + void *syms_base = (void *) symtabsec->sh_offset; + void *loc_base = (void *) target_section->sh_offset; + Elf64_Addr addr_base = target_section->sh_addr; + struct elf_info elf_info; + const char *strtab; + + if (symtabsec->sh_link >= ehdr->e_shnum) { + /* Invalid strtab section number */ + pr_err("Invalid string table section index %d\n", + symtabsec->sh_link); + return -ENOEXEC; + } + /* String table for the associated symbol table. */ + strtab = (const char *) sechdrs[symtabsec->sh_link].sh_offset; + + elf_init_elf_info(ehdr, sechdrs, &elf_info); + + return elf64_apply_relocate_add(&elf_info, strtab, rela, num_rela, + syms_base, loc_base, addr_base, + true, true, "kexec purgatory"); +} + +/** + * setup_purgatory() - setup the purgatory runtime variables + * @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. + * @stack_top: Address where the purgatory can place its stack. + * @debug: Can the purgatory print messages to the console? + * + * Return: 0 on success, or negative errno on error. + */ +int setup_purgatory(struct kimage *image, const void *slave_code, + const void *fdt, unsigned long kernel_load_addr, + unsigned long fdt_load_addr, unsigned long stack_top, + int debug) +{ + int ret, tree_node; + const void *prop; + unsigned long opal_base, opal_entry; + uint64_t toc; + unsigned int *slave_code_buf, master_entry; + struct elf_info purg_info; + + slave_code_buf = kmalloc(SLAVE_CODE_SIZE, GFP_KERNEL); + if (!slave_code_buf) + return -ENOMEM; + + /* Get the slave code from the new kernel and put it in purgatory. */ + ret = kexec_purgatory_get_set_symbol(image, "purgatory_start", + slave_code_buf, SLAVE_CODE_SIZE, + true); + if (ret) { + kfree(slave_code_buf); + return ret; + } + + master_entry = slave_code_buf[0]; + memcpy(slave_code_buf, slave_code, SLAVE_CODE_SIZE); + slave_code_buf[0] = master_entry; + ret = kexec_purgatory_get_set_symbol(image, "purgatory_start", + slave_code_buf, SLAVE_CODE_SIZE, + false); + kfree(slave_code_buf); + + ret = kexec_purgatory_get_set_symbol(image, "kernel", &kernel_load_addr, + sizeof(kernel_load_addr), false); + if (ret) + return ret; + ret = kexec_purgatory_get_set_symbol(image, "dt_offset", &fdt_load_addr, + sizeof(fdt_load_addr), false); + if (ret) + return ret; + + tree_node = fdt_path_offset(fdt, "/ibm,opal"); + if (tree_node >= 0) { + prop = fdt_getprop(fdt, tree_node, "opal-base-address", NULL); + if (!prop) { + pr_err("OPAL address not found in the device tree.\n"); + return -EINVAL; + } + opal_base = fdt64_to_cpu((const fdt64_t *) prop); + + prop = fdt_getprop(fdt, tree_node, "opal-entry-address", NULL); + if (!prop) { + pr_err("OPAL address not found in the device tree.\n"); + return -EINVAL; + } + opal_entry = fdt64_to_cpu((const fdt64_t *) prop); + + ret = kexec_purgatory_get_set_symbol(image, "opal_base", + &opal_base, + sizeof(opal_base), false); + if (ret) + return ret; + ret = kexec_purgatory_get_set_symbol(image, "opal_entry", + &opal_entry, + sizeof(opal_entry), false); + if (ret) + return ret; + } + + ret = kexec_purgatory_get_set_symbol(image, "stack", &stack_top, + sizeof(stack_top), false); + if (ret) + return ret; + + elf_init_elf_info(image->purgatory_info.ehdr, + image->purgatory_info.sechdrs, &purg_info); + toc = my_r2(&purg_info); + ret = kexec_purgatory_get_set_symbol(image, "my_toc", &toc, sizeof(toc), + false); + if (ret) + return ret; + + pr_debug("Purgatory TOC is at 0x%llx\n", toc); + + ret = kexec_purgatory_get_set_symbol(image, "debug", &debug, + sizeof(debug), false); + if (ret) + return ret; + if (!debug) + pr_debug("Disabling purgatory output.\n"); + + return 0; +} + +#endif /* CONFIG_KEXEC_FILE */ -- 1.9.1