Re: [PATCH 2/2] efi: Remove global 'memmap'

Ard Biesheuvel
2016-04-11T13:17:58Z

On 11 April 2016 at 15:03, Matt Fleming <matt@codeblueprint.co.uk> wrote:
> Abolish the poorly named EFI memory map named 'memmap'. It is shadowed
> by a bunch of local definitions in various files and having two ways
> to access the EFI memory map ('efi->memmap' vs 'memmap') is rather
> confusing.
>
> Furthermore, ia64 doesn't even provide this global object, which has
> caused issues when trying to write generic EFI memmap code.
>
> Replace all occurrences with efi.memmap.
>
> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> Cc: "Luck, Tony" <tony.luck@intel.com>
> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
> ---
> arch/x86/platform/efi/efi.c | 86 +++++++++++++++++++++-----------------
> drivers/firmware/efi/arm-init.c | 20 ++++-----
> drivers/firmware/efi/arm-runtime.c | 13 +++---
> drivers/firmware/efi/fake_mem.c | 40 +++++++++---------
> include/linux/efi.h | 7 ++--
> 5 files changed, 86 insertions(+), 80 deletions(-)
>
> diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
> index bd8f03301b59..88d2fb2cb3ef 100644
> --- a/arch/x86/platform/efi/efi.c
> +++ b/arch/x86/platform/efi/efi.c
> @@ -56,8 +56,6 @@
>
> #define EFI_DEBUG
>
> -struct efi_memory_map memmap;
> -
> static struct efi efi_phys __initdata;
> static efi_system_table_t efi_systab __initdata;
>
> @@ -207,15 +205,13 @@ int __init efi_memblock_x86_reserve_range(void)
> #else
> pmap = (e->efi_memmap | ((__u64)e->efi_memmap_hi << 32));
> #endif
> - memmap.phys_map = pmap;
> - memmap.nr_map = e->efi_memmap_size /
> + efi.memmap.phys_map = pmap;
> + efi.memmap.nr_map = e->efi_memmap_size /
> e->efi_memdesc_size;
> - memmap.desc_size = e->efi_memdesc_size;
> - memmap.desc_version = e->efi_memdesc_version;
> -
> - memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
> + efi.memmap.desc_size = e->efi_memdesc_size;
> + efi.memmap.desc_version = e->efi_memdesc_version;
>
> - efi.memmap = &memmap;
> + memblock_reserve(pmap, efi.memmap.nr_map * efi.memmap.desc_size);
>
> return 0;
> }
> @@ -240,10 +236,14 @@ void __init efi_print_memmap(void)
>
> void __init efi_unmap_memmap(void)
> {
> + unsigned long size;
> +
> clear_bit(EFI_MEMMAP, &efi.flags);
> - if (memmap.map) {
> - early_memunmap(memmap.map, memmap.nr_map * memmap.desc_size);
> - memmap.map = NULL;
> +
> + size = efi.memmap.nr_map * efi.memmap.desc_size;
> + if (efi.memmap.map) {
> + early_memunmap(efi.memmap.map, size);
> + efi.memmap.map = NULL;
> }
> }
>
> @@ -432,17 +432,22 @@ static int __init efi_runtime_init(void)
>
> static int __init efi_memmap_init(void)
> {
> + unsigned long addr, size;
> +
> if (efi_enabled(EFI_PARAVIRT))
> return 0;
>
> /* Map the EFI memory map */
> - memmap.map = early_memremap((unsigned long)memmap.phys_map,
> - memmap.nr_map * memmap.desc_size);
> - if (memmap.map == NULL) {
> + size = efi.memmap.nr_map * efi.memmap.desc_size;
> + addr = (unsigned long)efi.memmap.phys_map;
> +
> + efi.memmap.map = early_memremap(addr, size);
> + if (efi.memmap.map == NULL) {
> pr_err("Could not map the memory map!\n");
> return -ENOMEM;
> }
> - memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
> +
> + efi.memmap.map_end = efi.memmap.map + size;
>
> if (add_efi_memmap)
> do_add_efi_memmap();
> @@ -544,7 +549,6 @@ void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
> void __init runtime_code_page_mkexec(void)
> {
> efi_memory_desc_t *md;
> - void *p;
>
> /* Make EFI runtime service code area executable */
> for_each_efi_memory_desc(md) {
> @@ -594,7 +598,6 @@ void __init old_map_region(efi_memory_desc_t *md)
> /* Merge contiguous regions of the same type and attribute */
> static void __init efi_merge_regions(void)
> {
> - void *p;
> efi_memory_desc_t *md, *prev_md = NULL;
>
> for_each_efi_memory_desc(md) {
> @@ -640,6 +643,7 @@ static void __init get_systab_virt_addr(efi_memory_desc_t *md)
> static void __init save_runtime_map(void)
> {
> #ifdef CONFIG_KEXEC_CORE
> + unsigned long desc_size;
> efi_memory_desc_t *md;
> void *tmp, *q = NULL;
> int count = 0;
> @@ -647,21 +651,23 @@ static void __init save_runtime_map(void)
> if (efi_enabled(EFI_OLD_MEMMAP))
> return;
>
> + desc_size = efi.memmap.desc_size;
> +
> for_each_efi_memory_desc(md) {
> if (!(md->attribute & EFI_MEMORY_RUNTIME) ||
> (md->type == EFI_BOOT_SERVICES_CODE) ||
> (md->type == EFI_BOOT_SERVICES_DATA))
> continue;
> - tmp = krealloc(q, (count + 1) * memmap.desc_size, GFP_KERNEL);
> + tmp = krealloc(q, (count + 1) * desc_size, GFP_KERNEL);
> if (!tmp)
> goto out;
> q = tmp;
>
> - memcpy(q + count * memmap.desc_size, md, memmap.desc_size);
> + memcpy(q + count * desc_size, md, desc_size);
> count++;
> }
>
> - efi_runtime_map_setup(q, count, memmap.desc_size);
> + efi_runtime_map_setup(q, count, desc_size);
> return;
>
> out:
> @@ -701,10 +707,10 @@ static inline void *efi_map_next_entry_reverse(void *entry)
> {
> /* Initial call */
> if (!entry)
> - return memmap.map_end - memmap.desc_size;
> + return efi.memmap.map_end - efi.memmap.desc_size;
>
> - entry -= memmap.desc_size;
> - if (entry < memmap.map)
> + entry -= efi.memmap.desc_size;
> + if (entry < efi.memmap.map)
> return NULL;
>
> return entry;
> @@ -746,10 +752,10 @@ static void *efi_map_next_entry(void *entry)
>
> /* Initial call */
> if (!entry)
> - return memmap.map;
> + return efi.memmap.map;
>
> - entry += memmap.desc_size;
> - if (entry >= memmap.map_end)
> + entry += efi.memmap.desc_size;
> + if (entry >= efi.memmap.map_end)
> return NULL;
>
> return entry;
> @@ -763,8 +769,11 @@ static void * __init efi_map_regions(int *count, int *pg_shift)
> {
> void *p, *new_memmap = NULL;
> unsigned long left = 0;
> + unsigned long desc_size;
> efi_memory_desc_t *md;
>
> + desc_size = efi.memmap.desc_size;
> +
> p = NULL;
> while ((p = efi_map_next_entry(p))) {
> md = p;
> @@ -779,7 +788,7 @@ static void * __init efi_map_regions(int *count, int *pg_shift)
> efi_map_region(md);
> get_systab_virt_addr(md);
>
> - if (left < memmap.desc_size) {
> + if (left < desc_size) {
> new_memmap = realloc_pages(new_memmap, *pg_shift);
> if (!new_memmap)
> return NULL;
> @@ -788,10 +797,9 @@ static void * __init efi_map_regions(int *count, int *pg_shift)
> (*pg_shift)++;
> }
>
> - memcpy(new_memmap + (*count * memmap.desc_size), md,
> - memmap.desc_size);
> + memcpy(new_memmap + (*count * desc_size), md, desc_size);
>
> - left -= memmap.desc_size;
> + left -= desc_size;
> (*count)++;
> }
>
> @@ -835,10 +843,10 @@ static void __init kexec_enter_virtual_mode(void)
>
> BUG_ON(!efi.systab);
>
> - num_pages = ALIGN(memmap.nr_map * memmap.desc_size, PAGE_SIZE);
> + num_pages = ALIGN(efi.memmap.nr_map * efi.memmap.desc_size, PAGE_SIZE);
> num_pages >>= PAGE_SHIFT;
>
> - if (efi_setup_page_tables(memmap.phys_map, num_pages)) {
> + if (efi_setup_page_tables(efi.memmap.phys_map, num_pages)) {
> clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
> return;
> }
> @@ -922,16 +930,16 @@ static void __init __efi_enter_virtual_mode(void)
>
> if (efi_is_native()) {
> status = phys_efi_set_virtual_address_map(
> - memmap.desc_size * count,
> - memmap.desc_size,
> - memmap.desc_version,
> + efi.memmap.desc_size * count,
> + efi.memmap.desc_size,
> + efi.memmap.desc_version,
> (efi_memory_desc_t *)__pa(new_memmap));
> } else {
> status = efi_thunk_set_virtual_address_map(
> efi_phys.set_virtual_address_map,
> - memmap.desc_size * count,
> - memmap.desc_size,
> - memmap.desc_version,
> + efi.memmap.desc_size * count,
> + efi.memmap.desc_size,
> + efi.memmap.desc_version,
> (efi_memory_desc_t *)__pa(new_memmap));
> }
>
> diff --git a/drivers/firmware/efi/arm-init.c b/drivers/firmware/efi/arm-init.c
> index 96e7fe548164..275187a86a19 100644
> --- a/drivers/firmware/efi/arm-init.c
> +++ b/drivers/firmware/efi/arm-init.c
> @@ -20,8 +20,6 @@
>
> #include <asm/efi.h>
>
> -struct efi_memory_map memmap;
> -
> u64 efi_system_table;
>
> static int __init is_normal_ram(efi_memory_desc_t *md)
> @@ -40,7 +38,7 @@ static phys_addr_t efi_to_phys(unsigned long addr)
> {
> efi_memory_desc_t *md;
>
> - for_each_efi_memory_desc_in_map(&memmap, md) {
> + for_each_efi_memory_desc(md) {
> if (!(md->attribute & EFI_MEMORY_RUNTIME))
> continue;
> if (md->virt_addr == 0)
> @@ -145,7 +143,7 @@ static __init void reserve_regions(void)
> if (efi_enabled(EFI_DBG))
> pr_info("Processing EFI memory map:\n");
>
> - for_each_efi_memory_desc_in_map(&memmap, md) {
> + for_each_efi_memory_desc(md) {
> paddr = md->phys_addr;
> npages = md->num_pages;
>
> @@ -186,9 +184,9 @@ void __init efi_init(void)
>
> efi_system_table = params.system_table;
>
> - memmap.phys_map = params.mmap;
> - memmap.map = early_memremap_ro(params.mmap, params.mmap_size);
> - if (memmap.map == NULL) {
> + efi.memmap.phys_map = params.mmap;
> + efi.memmap.map = early_memremap_ro(params.mmap, params.mmap_size);
> + if (efi.memmap.map == NULL) {
> /*
> * If we are booting via UEFI, the UEFI memory map is the only
> * description of memory we have, so there is little point in
> @@ -196,15 +194,15 @@ void __init efi_init(void)
> */
> panic("Unable to map EFI memory map.\n");
> }
> - memmap.map_end = memmap.map + params.mmap_size;
> - memmap.desc_size = params.desc_size;
> - memmap.desc_version = params.desc_ver;
> + efi.memmap.map_end = efi.memmap.map + params.mmap_size;
> + efi.memmap.desc_size = params.desc_size;
> + efi.memmap.desc_version = params.desc_ver;
>
> if (uefi_init() < 0)
> return;
>
> reserve_regions();
> - early_memunmap(memmap.map, params.mmap_size);
> + early_memunmap(efi.memmap.map, params.mmap_size);
> memblock_mark_nomap(params.mmap & PAGE_MASK,
> PAGE_ALIGN(params.mmap_size +
> (params.mmap & ~PAGE_MASK)));
> diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c
> index 1cfbfaf57a2d..0416d5d33e74 100644
> --- a/drivers/firmware/efi/arm-runtime.c
> +++ b/drivers/firmware/efi/arm-runtime.c
> @@ -89,6 +89,7 @@ static bool __init efi_virtmap_init(void)
> */
> static int __init arm_enable_runtime_services(void)
> {
> + phys_addr_t phys_map;

Is the sole purpose of this variable to prevent breaking the 80-column rule?

If so, please be aware that I intend to propose a patch that replaces
the ioremap_cache() below with a call to memremap(), but this is
another change that is gated by Russell merging my memremap patches
for ARM

> u64 mapsize;
>
> if (!efi_enabled(EFI_BOOT)) {
> @@ -103,15 +104,15 @@ static int __init arm_enable_runtime_services(void)
>
> pr_info("Remapping and enabling EFI services.\n");
>
> - mapsize = memmap.map_end - memmap.map;
> - memmap.map = (__force void *)ioremap_cache(memmap.phys_map,
> - mapsize);
> - if (!memmap.map) {
> + mapsize = efi.memmap.map_end - efi.memmap.map;
> + phys_map = efi.memmap.phys_map;
> +
> + efi.memmap.map = (__force void *)ioremap_cache(phys_map, mapsize);
> + if (!efi.memmap.map) {
> pr_err("Failed to remap EFI memory map\n");
> return -ENOMEM;
> }
> - memmap.map_end = memmap.map + mapsize;
> - efi.memmap = &memmap;
> + efi.memmap.map_end = efi.memmap.map + mapsize;
>
> if (!efi_virtmap_init()) {
> pr_err("UEFI virtual mapping missing or invalid -- runtime services will not be available\n");
> diff --git a/drivers/firmware/efi/fake_mem.c b/drivers/firmware/efi/fake_mem.c
> index f55b75b2e1f4..48430aba13c1 100644
> --- a/drivers/firmware/efi/fake_mem.c
> +++ b/drivers/firmware/efi/fake_mem.c
> @@ -57,7 +57,7 @@ static int __init cmp_fake_mem(const void *x1, const void *x2)
> void __init efi_fake_memmap(void)
> {
> u64 start, end, m_start, m_end, m_attr;
> - int new_nr_map = memmap.nr_map;
> + int new_nr_map = efi.memmap.nr_map;
> efi_memory_desc_t *md;
> phys_addr_t new_memmap_phy;
> void *new_memmap;
> @@ -94,25 +94,25 @@ void __init efi_fake_memmap(void)
> }
>
> /* allocate memory for new EFI memmap */
> - new_memmap_phy = memblock_alloc(memmap.desc_size * new_nr_map,
> + new_memmap_phy = memblock_alloc(efi.memmap.desc_size * new_nr_map,
> PAGE_SIZE);
> if (!new_memmap_phy)
> return;
>
> /* create new EFI memmap */
> new_memmap = early_memremap(new_memmap_phy,
> - memmap.desc_size * new_nr_map);
> + efi.memmap.desc_size * new_nr_map);
> if (!new_memmap) {
> - memblock_free(new_memmap_phy, memmap.desc_size * new_nr_map);
> + memblock_free(new_memmap_phy, efi.memmap.desc_size * new_nr_map);
> return;
> }
>
> - for (old = memmap.map, new = new_memmap;
> - old < memmap.map_end;
> - old += memmap.desc_size, new += memmap.desc_size) {
> + for (old = efi.memmap.map, new = new_memmap;
> + old < efi.memmap.map_end;
> + old += efi.memmap.desc_size, new += efi.memmap.desc_size) {
>
> /* copy original EFI memory descriptor */
> - memcpy(new, old, memmap.desc_size);
> + memcpy(new, old, efi.memmap.desc_size);
> md = new;
> start = md->phys_addr;
> end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1;
> @@ -133,8 +133,8 @@ void __init efi_fake_memmap(void)
> md->num_pages = (m_end - md->phys_addr + 1) >>
> EFI_PAGE_SHIFT;
> /* latter part */
> - new += memmap.desc_size;
> - memcpy(new, old, memmap.desc_size);
> + new += efi.memmap.desc_size;
> + memcpy(new, old, efi.memmap.desc_size);
> md = new;
> md->phys_addr = m_end + 1;
> md->num_pages = (end - md->phys_addr + 1) >>
> @@ -146,16 +146,16 @@ void __init efi_fake_memmap(void)
> md->num_pages = (m_start - md->phys_addr) >>
> EFI_PAGE_SHIFT;
> /* middle part */
> - new += memmap.desc_size;
> - memcpy(new, old, memmap.desc_size);
> + new += efi.memmap.desc_size;
> + memcpy(new, old, efi.memmap.desc_size);
> md = new;
> md->attribute |= m_attr;
> md->phys_addr = m_start;
> md->num_pages = (m_end - m_start + 1) >>
> EFI_PAGE_SHIFT;
> /* last part */
> - new += memmap.desc_size;
> - memcpy(new, old, memmap.desc_size);
> + new += efi.memmap.desc_size;
> + memcpy(new, old, efi.memmap.desc_size);
> md = new;
> md->phys_addr = m_end + 1;
> md->num_pages = (end - m_end) >>
> @@ -168,8 +168,8 @@ void __init efi_fake_memmap(void)
> md->num_pages = (m_start - md->phys_addr) >>
> EFI_PAGE_SHIFT;
> /* latter part */
> - new += memmap.desc_size;
> - memcpy(new, old, memmap.desc_size);
> + new += efi.memmap.desc_size;
> + memcpy(new, old, efi.memmap.desc_size);
> md = new;
> md->phys_addr = m_start;
> md->num_pages = (end - md->phys_addr + 1) >>
> @@ -181,10 +181,10 @@ void __init efi_fake_memmap(void)
>
> /* swap into new EFI memmap */
> efi_unmap_memmap();
> - memmap.map = new_memmap;
> - memmap.phys_map = new_memmap_phy;
> - memmap.nr_map = new_nr_map;
> - memmap.map_end = memmap.map + memmap.nr_map * memmap.desc_size;
> + efi.memmap.map = new_memmap;
> + efi.memmap.phys_map = new_memmap_phy;
> + efi.memmap.nr_map = new_nr_map;
> + efi.memmap.map_end = efi.memmap.map + efi.memmap.nr_map * efi.memmap.desc_size;
> set_bit(EFI_MEMMAP, &efi.flags);
>
> /* print new EFI memmap */
> diff --git a/include/linux/efi.h b/include/linux/efi.h
> index 942b13863790..c2c0da49876e 100644
> --- a/include/linux/efi.h
> +++ b/include/linux/efi.h
> @@ -883,7 +883,7 @@ extern struct efi {
> efi_get_next_high_mono_count_t *get_next_high_mono_count;
> efi_reset_system_t *reset_system;
> efi_set_virtual_address_map_t *set_virtual_address_map;
> - struct efi_memory_map *memmap;
> + struct efi_memory_map memmap;
> unsigned long flags;
> } efi;
>
> @@ -945,7 +945,6 @@ extern void efi_initialize_iomem_resources(struct resource *code_resource,
> extern void efi_get_time(struct timespec *now);
> extern void efi_reserve_boot_services(void);
> extern int efi_get_fdt_params(struct efi_fdt_params *params);
> -extern struct efi_memory_map memmap;
> extern struct kobject *efi_kobj;
>
> extern int efi_reboot_quirk_mode;
> @@ -964,13 +963,13 @@ static inline void efi_fake_memmap(void) { }
> (md) = (void *)(md) + (m)->desc_size)
>
> /**
> - * for_each_efi_memory_desc - iterate over descriptors in efi->memmap
> + * for_each_efi_memory_desc - iterate over descriptors in efi.memmap
> * @md: the efi_memory_desc_t * iterator
> *
> * Once the loop finishes @md must not be accessed.
> */
> #define for_each_efi_memory_desc(md) \
> - for_each_efi_memory_desc_in_map(efi->memmap, md)
> + for_each_efi_memory_desc_in_map(&efi.memmap, md)
>
> /*
> * Format an EFI memory descriptor's type and attributes to a user-provided
> --
> 2.7.3
>