From 60fe3910bb029e3671ce7ac080a7acb7e032b9e0 Mon Sep 17 00:00:00 2001 From: Thiago Jung Bauermann Date: Tue, 29 Nov 2016 23:45:47 +1100 Subject: [PATCH] kexec_file: Allow arch-specific memory walking for kexec_add_buffer Allow architectures to specify a different memory walking function for kexec_add_buffer. x86 uses iomem to track reserved memory ranges, but PowerPC uses the memblock subsystem. Signed-off-by: Thiago Jung Bauermann Acked-by: Dave Young Acked-by: Balbir Singh Signed-off-by: Michael Ellerman --- include/linux/kexec.h | 29 ++++++++++++++++++++++++++++- kernel/kexec_file.c | 30 ++++++++++++++++++++++-------- kernel/kexec_internal.h | 16 ---------------- 3 files changed, 50 insertions(+), 25 deletions(-) diff --git a/include/linux/kexec.h b/include/linux/kexec.h index 406c33dcae13..5e320ddaaa82 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -148,7 +148,34 @@ struct kexec_file_ops { kexec_verify_sig_t *verify_sig; #endif }; -#endif + +/** + * struct kexec_buf - parameters for finding a place for a buffer in memory + * @image: kexec image in which memory to search. + * @buffer: Contents which will be copied to the allocated memory. + * @bufsz: Size of @buffer. + * @mem: On return will have address of the buffer in memory. + * @memsz: Size for the buffer in memory. + * @buf_align: Minimum alignment needed. + * @buf_min: The buffer can't be placed below this address. + * @buf_max: The buffer can't be placed above this address. + * @top_down: Allocate from top of memory. + */ +struct kexec_buf { + struct kimage *image; + char *buffer; + unsigned long bufsz; + unsigned long mem; + unsigned long memsz; + unsigned long buf_align; + unsigned long buf_min; + unsigned long buf_max; + bool top_down; +}; + +int __weak arch_kexec_walk_mem(struct kexec_buf *kbuf, + int (*func)(u64, u64, void *)); +#endif /* CONFIG_KEXEC_FILE */ struct kimage { kimage_entry_t head; diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index 037c321c5618..f865674bff51 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -428,6 +428,27 @@ static int locate_mem_hole_callback(u64 start, u64 end, void *arg) return locate_mem_hole_bottom_up(start, end, kbuf); } +/** + * arch_kexec_walk_mem - call func(data) on free memory regions + * @kbuf: Context info for the search. Also passed to @func. + * @func: Function to call for each memory region. + * + * 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 __weak arch_kexec_walk_mem(struct kexec_buf *kbuf, + int (*func)(u64, u64, void *)) +{ + if (kbuf->image->type == KEXEC_TYPE_CRASH) + return walk_iomem_res_desc(crashk_res.desc, + IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY, + crashk_res.start, crashk_res.end, + kbuf, func); + else + return walk_system_ram_res(0, ULONG_MAX, kbuf, func); +} + /* * Helper function for placing a buffer in a kexec segment. This assumes * that kexec_mutex is held. @@ -474,14 +495,7 @@ int kexec_add_buffer(struct kimage *image, char *buffer, unsigned long bufsz, kbuf->top_down = top_down; /* Walk the RAM ranges and allocate a suitable range for the buffer */ - if (image->type == KEXEC_TYPE_CRASH) - ret = walk_iomem_res_desc(crashk_res.desc, - IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY, - crashk_res.start, crashk_res.end, kbuf, - locate_mem_hole_callback); - else - ret = walk_system_ram_res(0, -1, kbuf, - locate_mem_hole_callback); + ret = arch_kexec_walk_mem(kbuf, locate_mem_hole_callback); if (ret != 1) { /* A suitable memory range could not be found for buffer */ return -EADDRNOTAVAIL; diff --git a/kernel/kexec_internal.h b/kernel/kexec_internal.h index 0a52315d9c62..4cef7e4706b0 100644 --- a/kernel/kexec_internal.h +++ b/kernel/kexec_internal.h @@ -20,22 +20,6 @@ struct kexec_sha_region { unsigned long len; }; -/* - * Keeps track of buffer parameters as provided by caller for requesting - * memory placement of buffer. - */ -struct kexec_buf { - struct kimage *image; - char *buffer; - unsigned long bufsz; - unsigned long mem; - unsigned long memsz; - unsigned long buf_align; - unsigned long buf_min; - unsigned long buf_max; - bool top_down; /* allocate from top of memory hole */ -}; - void kimage_file_post_load_cleanup(struct kimage *image); #else /* CONFIG_KEXEC_FILE */ static inline void kimage_file_post_load_cleanup(struct kimage *image) { } -- 2.30.2