diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/include/asm/e820/api.h | 3 | ||||
| -rw-r--r-- | arch/x86/kernel/e820.c | 78 | ||||
| -rw-r--r-- | arch/x86/kernel/kexec-bzimage64.c | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/setup.c | 4 | ||||
| -rw-r--r-- | arch/x86/power/hibernate_64.c | 4 |
5 files changed, 56 insertions, 37 deletions
diff --git a/arch/x86/include/asm/e820/api.h b/arch/x86/include/asm/e820/api.h index 2a6de16ad9b5..2c336d8a8593 100644 --- a/arch/x86/include/asm/e820/api.h +++ b/arch/x86/include/asm/e820/api.h @@ -3,9 +3,8 @@ #include <asm/e820/types.h> -/* see comment in arch/x86/kernel/e820.c */ extern struct e820_table *e820_table; -extern struct e820_table *e820_table_saved; +extern struct e820_table *e820_table_firmware; extern unsigned long pci_mem_start; diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c index 7d12433ad056..86d6d823e47e 100644 --- a/arch/x86/kernel/e820.c +++ b/arch/x86/kernel/e820.c @@ -27,23 +27,43 @@ #include <asm/cpufeature.h> /* - * The e820 table is the array that gets modified e.g. with command line parameters - * and that is also registered with modifications in the kernel resource tree - * with the iomem_resource as parent. + * The firmware and bootloader passes us an E820 table that is the primary + * physical memory layout description available about x86 systems. * - * The e820_table_saved is directly saved after the BIOS-provided memory map is - * copied. It doesn't get modified afterwards. It's registered for the - * /sys/firmware/memmap interface. + * The kernel takes the e820 memory layout and optionally modifies it with + * quirks and other tweaks, and feeds that into the generic Linux memory + * allocation code routines via a platform independent interface (memblock, etc.). * - * That memory map is not modified and is used as base for kexec. The kexec'd - * kernel should get the same memory map as the firmware provides. Then the - * user can e.g. boot the original kernel with mem=1G while still booting the - * next kernel with full memory. + * We organize the E820 table into two main data structures: + * + * - 'e820_table_firmware': the original firmware version passed to us by the + * bootloader - not modified by the kernel. We use this to: + * + * - inform the user about the firmware's notion of memory layout + * via /sys/firmware/memmap + * + * - the hibernation code uses it to generate a kernel-independent MD5 + * fingerprint of the physical memory layout of a system. + * + * - kexec, which is a bootloader in disguise, uses the original e820 + * layout to pass to the kexec-ed kernel. This way the original kernel + * can have a restricted e820 map while the kexec()-ed kexec-kernel + * can have access to full memory - etc. + * + * - 'e820_table': this is the main e820 table that is massaged by the + * low level x86 platform code, or modified by boot parameters, before + * passed on to higher level MM layers. + * + * Once the e820 map has been converted to the standard Linux memory layout + * information its role stops - modifying it has no effect and does not get + * re-propagated. So itsmain role is a temporary bootstrap storage of firmware + * specific memory layout data during early bootup. */ -static struct e820_table e820_table_init __initdata; -static struct e820_table initial_e820_table_saved __initdata; -struct e820_table *e820_table __refdata = &e820_table_init; -struct e820_table *e820_table_saved __refdata = &initial_e820_table_saved; +static struct e820_table e820_table_init __initdata; +static struct e820_table e820_table_firmware_init __initdata; + +struct e820_table *e820_table __refdata = &e820_table_init; +struct e820_table *e820_table_firmware __refdata = &e820_table_firmware_init; /* For PCI or other memory-mapped resources */ unsigned long pci_mem_start = 0xaeedbabe; @@ -497,10 +517,10 @@ u64 __init e820_update_range(u64 start, u64 size, unsigned old_type, return __e820_update_range(e820_table, start, size, old_type, new_type); } -static u64 __init e820_update_range_saved(u64 start, u64 size, +static u64 __init e820_update_range_firmware(u64 start, u64 size, unsigned old_type, unsigned new_type) { - return __e820_update_range(e820_table_saved, start, size, old_type, + return __e820_update_range(e820_table_firmware, start, size, old_type, new_type); } @@ -572,9 +592,9 @@ void __init update_e820(void) printk(KERN_INFO "e820: modified physical RAM map:\n"); e820_print_map("modified"); } -static void __init update_e820_table_saved(void) +static void __init update_e820_table_firmware(void) { - sanitize_e820_table(e820_table_saved->entries, ARRAY_SIZE(e820_table_saved->entries), &e820_table_saved->nr_entries); + sanitize_e820_table(e820_table_firmware->entries, ARRAY_SIZE(e820_table_firmware->entries), &e820_table_firmware->nr_entries); } #define MAX_GAP_END 0x100000000ull /* @@ -648,7 +668,7 @@ __init void e820_setup_gap(void) /* * Called late during init, in free_initmem(). * - * Initial e820 and e820_table_saved are largish __initdata arrays. + * Initial e820 and e820_table_firmware are largish __initdata arrays. * Copy them to (usually much smaller) dynamically allocated area. * This is done after all tweaks we ever do to them: * all functions which modify them are __init functions, @@ -665,11 +685,11 @@ __init void e820_reallocate_tables(void) memcpy(n, e820_table, size); e820_table = n; - size = offsetof(struct e820_table, entries) + sizeof(struct e820_entry) * e820_table_saved->nr_entries; + size = offsetof(struct e820_table, entries) + sizeof(struct e820_entry) * e820_table_firmware->nr_entries; n = kmalloc(size, GFP_KERNEL); BUG_ON(!n); - memcpy(n, e820_table_saved, size); - e820_table_saved = n; + memcpy(n, e820_table_firmware, size); + e820_table_firmware = n; } /** @@ -745,7 +765,7 @@ core_initcall(e820_mark_nvs_memory); #endif /* - * pre allocated 4k and reserved it in memblock and e820_table_saved + * pre allocated 4k and reserved it in memblock and e820_table_firmware */ u64 __init early_reserve_e820(u64 size, u64 align) { @@ -753,9 +773,9 @@ u64 __init early_reserve_e820(u64 size, u64 align) addr = __memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE); if (addr) { - e820_update_range_saved(addr, size, E820_RAM, E820_RESERVED); - printk(KERN_INFO "e820: update e820_table_saved for early_reserve_e820\n"); - update_e820_table_saved(); + e820_update_range_firmware(addr, size, E820_RAM, E820_RESERVED); + printk(KERN_INFO "e820: update e820_table_firmware for early_reserve_e820\n"); + update_e820_table_firmware(); } return addr; @@ -1034,8 +1054,8 @@ void __init e820_reserve_resources(void) res++; } - for (i = 0; i < e820_table_saved->nr_entries; i++) { - struct e820_entry *entry = &e820_table_saved->entries[i]; + for (i = 0; i < e820_table_firmware->nr_entries; i++) { + struct e820_entry *entry = &e820_table_firmware->entries[i]; firmware_map_add_early(entry->addr, entry->addr + entry->size, e820_type_to_string(entry->type)); @@ -1145,7 +1165,7 @@ void __init e820__memory_setup(void) char *who; who = x86_init.resources.memory_setup(); - memcpy(e820_table_saved, e820_table, sizeof(struct e820_table)); + memcpy(e820_table_firmware, e820_table, sizeof(struct e820_table)); printk(KERN_INFO "e820: BIOS-provided physical RAM map:\n"); e820_print_map(who); } diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c index 3e5c995e1718..a8c9563557c9 100644 --- a/arch/x86/kernel/kexec-bzimage64.c +++ b/arch/x86/kernel/kexec-bzimage64.c @@ -100,14 +100,14 @@ static int setup_e820_entries(struct boot_params *params) { unsigned int nr_e820_entries; - nr_e820_entries = e820_table_saved->nr_entries; + nr_e820_entries = e820_table_firmware->nr_entries; /* TODO: Pass entries more than E820MAX in bootparams setup data */ if (nr_e820_entries > E820MAX) nr_e820_entries = E820MAX; params->e820_entries = nr_e820_entries; - memcpy(¶ms->e820_table, &e820_table_saved->entries, nr_e820_entries*sizeof(struct e820_entry)); + memcpy(¶ms->e820_table, &e820_table_firmware->entries, nr_e820_entries*sizeof(struct e820_entry)); return 0; } diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index a8d0e388b358..f905430d7b04 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -459,7 +459,7 @@ static void __init e820_reserve_setup_data(void) } sanitize_e820_table(e820_table->entries, ARRAY_SIZE(e820_table->entries), &e820_table->nr_entries); - memcpy(e820_table_saved, e820_table, sizeof(struct e820_table)); + memcpy(e820_table_firmware, e820_table, sizeof(struct e820_table)); printk(KERN_INFO "extended physical RAM map:\n"); e820_print_map("reserve setup_data"); } @@ -1026,7 +1026,7 @@ void __init setup_arch(char **cmdline_p) early_dump_pci_devices(); #endif - /* update the e820_table_saved too */ + /* update the e820_table_firmware too */ e820_reserve_setup_data(); finish_e820_parsing(); diff --git a/arch/x86/power/hibernate_64.c b/arch/x86/power/hibernate_64.c index 1bfda425879c..053801b022dd 100644 --- a/arch/x86/power/hibernate_64.c +++ b/arch/x86/power/hibernate_64.c @@ -231,7 +231,7 @@ static int get_e820_md5(struct e820_table *table, void *buf) static void hibernation_e820_save(void *buf) { - get_e820_md5(e820_table_saved, buf); + get_e820_md5(e820_table_firmware, buf); } static bool hibernation_e820_mismatch(void *buf) @@ -244,7 +244,7 @@ static bool hibernation_e820_mismatch(void *buf) if (!memcmp(result, buf, MD5_DIGEST_SIZE)) return false; - ret = get_e820_md5(e820_table_saved, result); + ret = get_e820_md5(e820_table_firmware, result); if (ret) return true; |