[PATCH v17 4/6] PowerPC/kexec: make the update_cpus_node() function public

Hari Bathini hbathini at linux.ibm.com
Sat Mar 2 05:18:38 PST 2024



On 26/02/24 2:11 pm, Sourabh Jain wrote:
> Move the update_cpus_node() from kexec/{file_load_64.c => core_64.c}
> to allow other kexec components to use it.
> 
> Later in the series, this function is used for in-kernel updates
> to the kdump image during CPU/memory hotplug or online/offline events for
> both kexec_load and kexec_file_load syscalls.
> 
> No functional changes are intended.
> 

Looks good to me.

Acked-by: Hari Bathini <hbathini at linux.ibm.com>

> Signed-off-by: Sourabh Jain <sourabhjain at linux.ibm.com>
> Cc: Akhil Raj <lf32.dev at gmail.com>
> Cc: Andrew Morton <akpm at linux-foundation.org>
> Cc: Aneesh Kumar K.V <aneesh.kumar at kernel.org>
> Cc: Baoquan He <bhe at redhat.com>
> Cc: Borislav Petkov (AMD) <bp at alien8.de>
> Cc: Boris Ostrovsky <boris.ostrovsky at oracle.com>
> Cc: Christophe Leroy <christophe.leroy at csgroup.eu>
> Cc: Dave Hansen <dave.hansen at linux.intel.com>
> Cc: Dave Young <dyoung at redhat.com>
> Cc: David Hildenbrand <david at redhat.com>
> Cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
> Cc: Hari Bathini <hbathini at linux.ibm.com>
> Cc: Laurent Dufour <laurent.dufour at fr.ibm.com>
> Cc: Mahesh Salgaonkar <mahesh at linux.ibm.com>
> Cc: Michael Ellerman <mpe at ellerman.id.au>
> Cc: Mimi Zohar <zohar at linux.ibm.com>
> Cc: Naveen N Rao <naveen at kernel.org>
> Cc: Oscar Salvador <osalvador at suse.de>
> Cc: Thomas Gleixner <tglx at linutronix.de>
> Cc: Valentin Schneider <vschneid at redhat.com>
> Cc: Vivek Goyal <vgoyal at redhat.com>
> Cc: kexec at lists.infradead.org
> Cc: x86 at kernel.org
> ---
>   arch/powerpc/include/asm/kexec.h  |  4 ++
>   arch/powerpc/kexec/core_64.c      | 91 +++++++++++++++++++++++++++++++
>   arch/powerpc/kexec/file_load_64.c | 87 -----------------------------
>   3 files changed, 95 insertions(+), 87 deletions(-)
> 
> diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
> index fdb90e24dc74..d9ff4d0e392d 100644
> --- a/arch/powerpc/include/asm/kexec.h
> +++ b/arch/powerpc/include/asm/kexec.h
> @@ -185,6 +185,10 @@ static inline void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *))
>   
>   #endif /* CONFIG_CRASH_DUMP */
>   
> +#if defined(CONFIG_KEXEC_FILE) || defined(CONFIG_CRASH_DUMP)
> +int update_cpus_node(void *fdt);
> +#endif
> +
>   #ifdef CONFIG_PPC_BOOK3S_64
>   #include <asm/book3s/64/kexec.h>
>   #endif
> diff --git a/arch/powerpc/kexec/core_64.c b/arch/powerpc/kexec/core_64.c
> index 762e4d09aacf..85050be08a23 100644
> --- a/arch/powerpc/kexec/core_64.c
> +++ b/arch/powerpc/kexec/core_64.c
> @@ -17,6 +17,7 @@
>   #include <linux/cpu.h>
>   #include <linux/hardirq.h>
>   #include <linux/of.h>
> +#include <linux/libfdt.h>
>   
>   #include <asm/page.h>
>   #include <asm/current.h>
> @@ -30,6 +31,7 @@
>   #include <asm/hw_breakpoint.h>
>   #include <asm/svm.h>
>   #include <asm/ultravisor.h>
> +#include <asm/crashdump-ppc64.h>
>   
>   int machine_kexec_prepare(struct kimage *image)
>   {
> @@ -419,3 +421,92 @@ static int __init export_htab_values(void)
>   }
>   late_initcall(export_htab_values);
>   #endif /* CONFIG_PPC_64S_HASH_MMU */
> +
> +#if defined(CONFIG_KEXEC_FILE) || defined(CONFIG_CRASH_DUMP)
> +/**
> + * add_node_props - Reads node properties from device node structure and add
> + *                  them to fdt.
> + * @fdt:            Flattened device tree of the kernel
> + * @node_offset:    offset of the node to add a property at
> + * @dn:             device node pointer
> + *
> + * Returns 0 on success, negative errno on error.
> + */
> +static int add_node_props(void *fdt, int node_offset, const struct device_node *dn)
> +{
> +	int ret = 0;
> +	struct property *pp;
> +
> +	if (!dn)
> +		return -EINVAL;
> +
> +	for_each_property_of_node(dn, pp) {
> +		ret = fdt_setprop(fdt, node_offset, pp->name, pp->value, pp->length);
> +		if (ret < 0) {
> +			pr_err("Unable to add %s property: %s\n", pp->name, fdt_strerror(ret));
> +			return ret;
> +		}
> +	}
> +	return ret;
> +}
> +
> +/**
> + * update_cpus_node - Update cpus node of flattened device tree using of_root
> + *                    device node.
> + * @fdt:              Flattened device tree of the kernel.
> + *
> + * Returns 0 on success, negative errno on error.
> + */
> +int update_cpus_node(void *fdt)
> +{
> +	struct device_node *cpus_node, *dn;
> +	int cpus_offset, cpus_subnode_offset, ret = 0;
> +
> +	cpus_offset = fdt_path_offset(fdt, "/cpus");
> +	if (cpus_offset < 0 && cpus_offset != -FDT_ERR_NOTFOUND) {
> +		pr_err("Malformed device tree: error reading /cpus node: %s\n",
> +		       fdt_strerror(cpus_offset));
> +		return cpus_offset;
> +	}
> +
> +	if (cpus_offset > 0) {
> +		ret = fdt_del_node(fdt, cpus_offset);
> +		if (ret < 0) {
> +			pr_err("Error deleting /cpus node: %s\n", fdt_strerror(ret));
> +			return -EINVAL;
> +		}
> +	}
> +
> +	/* Add cpus node to fdt */
> +	cpus_offset = fdt_add_subnode(fdt, fdt_path_offset(fdt, "/"), "cpus");
> +	if (cpus_offset < 0) {
> +		pr_err("Error creating /cpus node: %s\n", fdt_strerror(cpus_offset));
> +		return -EINVAL;
> +	}
> +
> +	/* Add cpus node properties */
> +	cpus_node = of_find_node_by_path("/cpus");
> +	ret = add_node_props(fdt, cpus_offset, cpus_node);
> +	of_node_put(cpus_node);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* Loop through all subnodes of cpus and add them to fdt */
> +	for_each_node_by_type(dn, "cpu") {
> +		cpus_subnode_offset = fdt_add_subnode(fdt, cpus_offset, dn->full_name);
> +		if (cpus_subnode_offset < 0) {
> +			pr_err("Unable to add %s subnode: %s\n", dn->full_name,
> +			       fdt_strerror(cpus_subnode_offset));
> +			ret = cpus_subnode_offset;
> +			goto out;
> +		}
> +
> +		ret = add_node_props(fdt, cpus_subnode_offset, dn);
> +		if (ret < 0)
> +			goto out;
> +	}
> +out:
> +	of_node_put(dn);
> +	return ret;
> +}
> +#endif /* CONFIG_KEXEC_FILE || CONFIG_CRASH_DUMP */
> diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
> index 6a01f62b8fcf..4b94c31e3172 100644
> --- a/arch/powerpc/kexec/file_load_64.c
> +++ b/arch/powerpc/kexec/file_load_64.c
> @@ -838,93 +838,6 @@ unsigned int kexec_extra_fdt_size_ppc64(struct kimage *image)
>   	return extra_size + kdump_extra_fdt_size_ppc64(image);
>   }
>   
> -/**
> - * add_node_props - Reads node properties from device node structure and add
> - *                  them to fdt.
> - * @fdt:            Flattened device tree of the kernel
> - * @node_offset:    offset of the node to add a property at
> - * @dn:             device node pointer
> - *
> - * Returns 0 on success, negative errno on error.
> - */
> -static int add_node_props(void *fdt, int node_offset, const struct device_node *dn)
> -{
> -	int ret = 0;
> -	struct property *pp;
> -
> -	if (!dn)
> -		return -EINVAL;
> -
> -	for_each_property_of_node(dn, pp) {
> -		ret = fdt_setprop(fdt, node_offset, pp->name, pp->value, pp->length);
> -		if (ret < 0) {
> -			pr_err("Unable to add %s property: %s\n", pp->name, fdt_strerror(ret));
> -			return ret;
> -		}
> -	}
> -	return ret;
> -}
> -
> -/**
> - * update_cpus_node - Update cpus node of flattened device tree using of_root
> - *                    device node.
> - * @fdt:              Flattened device tree of the kernel.
> - *
> - * Returns 0 on success, negative errno on error.
> - */
> -static int update_cpus_node(void *fdt)
> -{
> -	struct device_node *cpus_node, *dn;
> -	int cpus_offset, cpus_subnode_offset, ret = 0;
> -
> -	cpus_offset = fdt_path_offset(fdt, "/cpus");
> -	if (cpus_offset < 0 && cpus_offset != -FDT_ERR_NOTFOUND) {
> -		pr_err("Malformed device tree: error reading /cpus node: %s\n",
> -		       fdt_strerror(cpus_offset));
> -		return cpus_offset;
> -	}
> -
> -	if (cpus_offset > 0) {
> -		ret = fdt_del_node(fdt, cpus_offset);
> -		if (ret < 0) {
> -			pr_err("Error deleting /cpus node: %s\n", fdt_strerror(ret));
> -			return -EINVAL;
> -		}
> -	}
> -
> -	/* Add cpus node to fdt */
> -	cpus_offset = fdt_add_subnode(fdt, fdt_path_offset(fdt, "/"), "cpus");
> -	if (cpus_offset < 0) {
> -		pr_err("Error creating /cpus node: %s\n", fdt_strerror(cpus_offset));
> -		return -EINVAL;
> -	}
> -
> -	/* Add cpus node properties */
> -	cpus_node = of_find_node_by_path("/cpus");
> -	ret = add_node_props(fdt, cpus_offset, cpus_node);
> -	of_node_put(cpus_node);
> -	if (ret < 0)
> -		return ret;
> -
> -	/* Loop through all subnodes of cpus and add them to fdt */
> -	for_each_node_by_type(dn, "cpu") {
> -		cpus_subnode_offset = fdt_add_subnode(fdt, cpus_offset, dn->full_name);
> -		if (cpus_subnode_offset < 0) {
> -			pr_err("Unable to add %s subnode: %s\n", dn->full_name,
> -			       fdt_strerror(cpus_subnode_offset));
> -			ret = cpus_subnode_offset;
> -			goto out;
> -		}
> -
> -		ret = add_node_props(fdt, cpus_subnode_offset, dn);
> -		if (ret < 0)
> -			goto out;
> -	}
> -out:
> -	of_node_put(dn);
> -	return ret;
> -}
> -
>   static int copy_property(void *fdt, int node_offset, const struct device_node *dn,
>   			 const char *propname)
>   {



More information about the kexec mailing list