[PATCH v2] initramfs: Provide a common initrd reserve function
Palmer Dabbelt
palmer at dabbelt.com
Thu Jan 14 21:33:03 EST 2021
On Wed, 13 Jan 2021 18:33:58 PST (-0800), wangkefeng.wang at huawei.com wrote:
> The ARM and riscv have same logic to check and reserve
> the memory of initrd, let's provide a common function to
> reduce duplicated code.
>
> Add __LINUX_INITRD_H define in initrd.h to prevent build error
> (found by kernel test robot <lkp at intel.com>) from the multiple
> inclusion of same header file multiple time.
This is doing a bunch of different things:
* Fixing the lack of a preprocessor guard in initrd.h
* Adding some generic code.
* Converting two architectures over to that generic code.
It needs to be split into four patches. I'm happy to take them via the RISC-V
tree (with an Ack from for the arch/arm/ stuff), but not all together.
It looks like csky copied this as well, they at least have exactly the same
message.
> Signed-off-by: Kefeng Wang <wangkefeng.wang at huawei.com>
> ---
> v2: fix build err
>
> arch/arm/mm/init.c | 43 +---------------------------------
> arch/riscv/mm/init.c | 53 +-----------------------------------------
> include/linux/initrd.h | 11 +++++++++
> init/initramfs.c | 45 +++++++++++++++++++++++++++++++++++
> 4 files changed, 58 insertions(+), 94 deletions(-)
>
> diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c
> index 828a2561b229..a29e14cd626c 100644
> --- a/arch/arm/mm/init.c
> +++ b/arch/arm/mm/init.c
> @@ -153,47 +153,6 @@ phys_addr_t __init arm_memblock_steal(phys_addr_t size, phys_addr_t align)
> return phys;
> }
>
> -static void __init arm_initrd_init(void)
> -{
> -#ifdef CONFIG_BLK_DEV_INITRD
> - phys_addr_t start;
> - unsigned long size;
> -
> - initrd_start = initrd_end = 0;
> -
> - if (!phys_initrd_size)
> - return;
> -
> - /*
> - * Round the memory region to page boundaries as per free_initrd_mem()
> - * This allows us to detect whether the pages overlapping the initrd
> - * are in use, but more importantly, reserves the entire set of pages
> - * as we don't want these pages allocated for other purposes.
> - */
> - start = round_down(phys_initrd_start, PAGE_SIZE);
> - size = phys_initrd_size + (phys_initrd_start - start);
> - size = round_up(size, PAGE_SIZE);
> -
> - if (!memblock_is_region_memory(start, size)) {
> - pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region - disabling initrd\n",
> - (u64)start, size);
> - return;
> - }
> -
> - if (memblock_is_region_reserved(start, size)) {
> - pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region - disabling initrd\n",
> - (u64)start, size);
> - return;
> - }
> -
> - memblock_reserve(start, size);
> -
> - /* Now convert initrd to virtual addresses */
> - initrd_start = __phys_to_virt(phys_initrd_start);
> - initrd_end = initrd_start + phys_initrd_size;
> -#endif
> -}
> -
> #ifdef CONFIG_CPU_ICACHE_MISMATCH_WORKAROUND
> void check_cpu_icache_size(int cpuid)
> {
> @@ -215,7 +174,7 @@ void __init arm_memblock_init(const struct machine_desc *mdesc)
> /* Register the kernel text, kernel data and initrd with memblock. */
> memblock_reserve(__pa(KERNEL_START), KERNEL_END - KERNEL_START);
>
> - arm_initrd_init();
> + reserve_initrd_mem();
>
> arm_mm_memblock_reserve();
>
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index da53902ef0fc..93cba0d3f43f 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -105,55 +105,6 @@ void __init mem_init(void)
> print_vm_layout();
> }
>
> -#ifdef CONFIG_BLK_DEV_INITRD
> -static void __init setup_initrd(void)
> -{
> - phys_addr_t start;
> - unsigned long size;
> -
> - /* Ignore the virtul address computed during device tree parsing */
> - initrd_start = initrd_end = 0;
> -
> - if (!phys_initrd_size)
> - return;
> - /*
> - * Round the memory region to page boundaries as per free_initrd_mem()
> - * This allows us to detect whether the pages overlapping the initrd
> - * are in use, but more importantly, reserves the entire set of pages
> - * as we don't want these pages allocated for other purposes.
> - */
> - start = round_down(phys_initrd_start, PAGE_SIZE);
> - size = phys_initrd_size + (phys_initrd_start - start);
> - size = round_up(size, PAGE_SIZE);
> -
> - if (!memblock_is_region_memory(start, size)) {
> - pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region",
> - (u64)start, size);
> - goto disable;
> - }
> -
> - if (memblock_is_region_reserved(start, size)) {
> - pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region\n",
> - (u64)start, size);
> - goto disable;
> - }
> -
> - memblock_reserve(start, size);
> - /* Now convert initrd to virtual addresses */
> - initrd_start = (unsigned long)__va(phys_initrd_start);
> - initrd_end = initrd_start + phys_initrd_size;
> - initrd_below_start_ok = 1;
> -
> - pr_info("Initial ramdisk at: 0x%p (%lu bytes)\n",
> - (void *)(initrd_start), size);
> - return;
> -disable:
> - pr_cont(" - disabling initrd\n");
> - initrd_start = 0;
> - initrd_end = 0;
> -}
> -#endif /* CONFIG_BLK_DEV_INITRD */
> -
> void __init setup_bootmem(void)
> {
> phys_addr_t mem_start = 0;
> @@ -198,9 +149,7 @@ void __init setup_bootmem(void)
> dma32_phys_limit = min(4UL * SZ_1G, (unsigned long)PFN_PHYS(max_low_pfn));
> set_max_mapnr(max_low_pfn);
>
> -#ifdef CONFIG_BLK_DEV_INITRD
> - setup_initrd();
> -#endif /* CONFIG_BLK_DEV_INITRD */
> + reserve_initrd_mem();
>
> /*
> * Avoid using early_init_fdt_reserve_self() since __pa() does
> diff --git a/include/linux/initrd.h b/include/linux/initrd.h
> index 8db6f8c8030b..85c15717af34 100644
> --- a/include/linux/initrd.h
> +++ b/include/linux/initrd.h
> @@ -1,5 +1,8 @@
> /* SPDX-License-Identifier: GPL-2.0 */
>
> +#ifndef __LINUX_INITRD_H
> +#define __LINUX_INITRD_H
> +
> #define INITRD_MINOR 250 /* shouldn't collide with /dev/ram* too soon ... */
>
> /* starting block # of image */
> @@ -15,6 +18,12 @@ extern int initrd_below_start_ok;
> extern unsigned long initrd_start, initrd_end;
> extern void free_initrd_mem(unsigned long, unsigned long);
>
> +#ifdef CONFIG_BLK_DEV_INITRD
> +extern void __init reserve_initrd_mem(void);
> +#else
> +static inline void __init reserve_initrd_mem(void) {}
> +#endif
> +
> extern phys_addr_t phys_initrd_start;
> extern unsigned long phys_initrd_size;
>
> @@ -24,3 +33,5 @@ extern char __initramfs_start[];
> extern unsigned long __initramfs_size;
>
> void console_on_rootfs(void);
> +
> +#endif /* __LINUX_INITRD_H */
> diff --git a/init/initramfs.c b/init/initramfs.c
> index 55b74d7e5260..f75c89e9d602 100644
> --- a/init/initramfs.c
> +++ b/init/initramfs.c
> @@ -535,6 +535,51 @@ extern unsigned long __initramfs_size;
> #include <linux/initrd.h>
> #include <linux/kexec.h>
>
> +void __init reserve_initrd_mem(void)
> +{
> + phys_addr_t start;
> + unsigned long size;
> +
> + /* Ignore the virtul address computed during device tree parsing */
> + initrd_start = initrd_end = 0;
> +
> + if (!phys_initrd_size)
> + return;
> + /*
> + * Round the memory region to page boundaries as per free_initrd_mem()
> + * This allows us to detect whether the pages overlapping the initrd
> + * are in use, but more importantly, reserves the entire set of pages
> + * as we don't want these pages allocated for other purposes.
> + */
> + start = round_down(phys_initrd_start, PAGE_SIZE);
> + size = phys_initrd_size + (phys_initrd_start - start);
> + size = round_up(size, PAGE_SIZE);
> +
> + if (!memblock_is_region_memory(start, size)) {
> + pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region",
> + (u64)start, size);
> + goto disable;
> + }
> +
> + if (memblock_is_region_reserved(start, size)) {
> + pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region\n",
> + (u64)start, size);
> + goto disable;
> + }
> +
> + memblock_reserve(start, size);
> + /* Now convert initrd to virtual addresses */
> + initrd_start = (unsigned long)__va(phys_initrd_start);
> + initrd_end = initrd_start + phys_initrd_size;
> + initrd_below_start_ok = 1;
> +
> + return;
> +disable:
> + pr_cont(" - disabling initrd\n");
> + initrd_start = 0;
> + initrd_end = 0;
> +}
> +
> void __weak __init free_initrd_mem(unsigned long start, unsigned long end)
> {
> #ifdef CONFIG_ARCH_KEEP_MEMBLOCK
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