diff options
Diffstat (limited to 'arch/x86/kernel/e820.c')
| -rw-r--r-- | arch/x86/kernel/e820.c | 49 |
1 files changed, 36 insertions, 13 deletions
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c index d78a586..532da61 100644 --- a/arch/x86/kernel/e820.c +++ b/arch/x86/kernel/e820.c @@ -20,10 +20,12 @@ #include <asm/setup.h> /* - * We organize the E820 table into two main data structures: + * We organize the E820 table into three 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: + * bootloader - not modified by the kernel. It is composed of two parts: + * the first 128 E820 memory entries in boot_params.e820_table and the remaining + * (if any) entries of the SETUP_E820_EXT nodes. We use this to: * * - inform the user about the firmware's notion of memory layout * via /sys/firmware/memmap @@ -31,6 +33,14 @@ * - the hibernation code uses it to generate a kernel-independent MD5 * fingerprint of the physical memory layout of a system. * + * - 'e820_table_kexec': a slightly modified (by the kernel) firmware version + * passed to us by the bootloader - the major difference between + * e820_table_firmware[] and this one is that, the latter marks the setup_data + * list created by the EFI boot stub as reserved, so that kexec can reuse the + * setup_data information in the second kernel. Besides, e820_table_kexec[] + * might also be modified by the kexec itself to fake a mptable. + * We use this to: + * * - 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 @@ -46,9 +56,11 @@ * specific memory layout data during early bootup. */ static struct e820_table e820_table_init __initdata; +static struct e820_table e820_table_kexec_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_kexec __refdata = &e820_table_kexec_init; struct e820_table *e820_table_firmware __refdata = &e820_table_firmware_init; /* For PCI or other memory-mapped resources */ @@ -470,9 +482,9 @@ u64 __init e820__range_update(u64 start, u64 size, enum e820_type old_type, enum return __e820__range_update(e820_table, start, size, old_type, new_type); } -static u64 __init e820__range_update_firmware(u64 start, u64 size, enum e820_type old_type, enum e820_type new_type) +static u64 __init e820__range_update_kexec(u64 start, u64 size, enum e820_type old_type, enum e820_type new_type) { - return __e820__range_update(e820_table_firmware, start, size, old_type, new_type); + return __e820__range_update(e820_table_kexec, start, size, old_type, new_type); } /* Remove a range of memory from the E820 table: */ @@ -546,9 +558,9 @@ void __init e820__update_table_print(void) e820__print_table("modified"); } -static void __init e820__update_table_firmware(void) +static void __init e820__update_table_kexec(void) { - e820__update_table(e820_table_firmware); + e820__update_table(e820_table_kexec); } #define MAX_GAP_END 0x100000000ull @@ -623,7 +635,7 @@ __init void e820__setup_pci_gap(void) /* * Called late during init, in free_initmem(). * - * Initial e820_table and e820_table_firmware are largish __initdata arrays. + * Initial e820_table and e820_table_kexec are largish __initdata arrays. * * Copy them to a (usually much smaller) dynamically allocated area that is * sized precisely after the number of e820 entries. @@ -643,6 +655,12 @@ __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_kexec->nr_entries; + n = kmalloc(size, GFP_KERNEL); + BUG_ON(!n); + memcpy(n, e820_table_kexec, size); + e820_table_kexec = n; + size = offsetof(struct e820_table, entries) + sizeof(struct e820_entry)*e820_table_firmware->nr_entries; n = kmalloc(size, GFP_KERNEL); BUG_ON(!n); @@ -669,6 +687,9 @@ void __init e820__memory_setup_extended(u64 phys_addr, u32 data_len) __append_e820_table(extmap, entries); e820__update_table(e820_table); + memcpy(e820_table_kexec, e820_table, sizeof(*e820_table_kexec)); + memcpy(e820_table_firmware, e820_table, sizeof(*e820_table_firmware)); + early_memunmap(sdata, data_len); pr_info("e820: extended physical RAM map:\n"); e820__print_table("extended"); @@ -727,7 +748,7 @@ core_initcall(e820__register_nvs_regions); /* * Allocate the requested number of bytes with the requsted alignment * and return (the physical address) to the caller. Also register this - * range in the 'firmware' E820 table as a reserved range. + * range in the 'kexec' E820 table as a reserved range. * * This allows kexec to fake a new mptable, as if it came from the real * system. @@ -738,9 +759,9 @@ u64 __init e820__memblock_alloc_reserved(u64 size, u64 align) addr = __memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE); if (addr) { - e820__range_update_firmware(addr, size, E820_TYPE_RAM, E820_TYPE_RESERVED); - pr_info("e820: update e820_table_firmware for e820__memblock_alloc_reserved()\n"); - e820__update_table_firmware(); + e820__range_update_kexec(addr, size, E820_TYPE_RAM, E820_TYPE_RESERVED); + pr_info("e820: update e820_table_kexec for e820__memblock_alloc_reserved()\n"); + e820__update_table_kexec(); } return addr; @@ -923,13 +944,13 @@ void __init e820__reserve_setup_data(void) while (pa_data) { data = early_memremap(pa_data, sizeof(*data)); e820__range_update(pa_data, sizeof(*data)+data->len, E820_TYPE_RAM, E820_TYPE_RESERVED_KERN); + e820__range_update_kexec(pa_data, sizeof(*data)+data->len, E820_TYPE_RAM, E820_TYPE_RESERVED_KERN); pa_data = data->next; early_memunmap(data, sizeof(*data)); } e820__update_table(e820_table); - - memcpy(e820_table_firmware, e820_table, sizeof(*e820_table_firmware)); + e820__update_table(e820_table_kexec); pr_info("extended physical RAM map:\n"); e820__print_table("reserve setup_data"); @@ -1062,6 +1083,7 @@ void __init e820__reserve_resources(void) res++; } + /* Expose the bootloader-provided memory layout to the sysfs. */ for (i = 0; i < e820_table_firmware->nr_entries; i++) { struct e820_entry *entry = e820_table_firmware->entries + i; @@ -1175,6 +1197,7 @@ void __init e820__memory_setup(void) who = x86_init.resources.memory_setup(); + memcpy(e820_table_kexec, e820_table, sizeof(*e820_table_kexec)); memcpy(e820_table_firmware, e820_table, sizeof(*e820_table_firmware)); pr_info("e820: BIOS-provided physical RAM map:\n"); |
