resource: Provide resource struct in resource walk callback

In preperation for a new function that will need additional resource
information during the resource walk, update the resource walk callback to
pass the resource structure.  Since the current callback start and end
arguments are pulled from the resource structure, the callback functions
can obtain them from the resource structure directly.
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Tested-by: Borislav Petkov <bp@suse.de>
Cc: kvm@vger.kernel.org
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: linuxppc-dev@lists.ozlabs.org
Link: https://lkml.kernel.org/r/20171020143059.3291-10-brijesh.singh@amd.com

arch/powerpc/kernel/machine_kexec_file_64.c

@@ -91,11 +91,13 @@ int arch_kimage_file_post_load_cleanup(struct kimage *image)
  * and that value will be returned. If all free regions are visited without
  * func returning non-zero, then zero will be returned.
  */
-int arch_kexec_walk_mem(struct kexec_buf *kbuf, int (*func)(u64, u64, void *))
+int arch_kexec_walk_mem(struct kexec_buf *kbuf,
+			int (*func)(struct resource *, void *))
 {
 	int ret = 0;
 	u64 i;
 	phys_addr_t mstart, mend;
+	struct resource res = { };
 
 	if (kbuf->top_down) {
 		for_each_free_mem_range_reverse(i, NUMA_NO_NODE, 0,
@@ -105,7 +107,9 @@ int arch_kexec_walk_mem(struct kexec_buf *kbuf, int (*func)(u64, u64, void *))
 			 * range while in kexec, end points to the last byte
 			 * in the range.
 			 */
-			ret = func(mstart, mend - 1, kbuf);
+			res.start = mstart;
+			res.end = mend - 1;
+			ret = func(&res, kbuf);
 			if (ret)
 				break;
 		}
@@ -117,7 +121,9 @@ int arch_kexec_walk_mem(struct kexec_buf *kbuf, int (*func)(u64, u64, void *))
 			 * range while in kexec, end points to the last byte
 			 * in the range.
 			 */
-			ret = func(mstart, mend - 1, kbuf);
+			res.start = mstart;
+			res.end = mend - 1;
+			ret = func(&res, kbuf);
 			if (ret)
 				break;
 		}

arch/x86/kernel/crash.c

@@ -209,7 +209,7 @@ void native_machine_crash_shutdown(struct pt_regs *regs)
 }
 
 #ifdef CONFIG_KEXEC_FILE
-static int get_nr_ram_ranges_callback(u64 start, u64 end, void *arg)
+static int get_nr_ram_ranges_callback(struct resource *res, void *arg)
 {
 	unsigned int *nr_ranges = arg;
 
@@ -342,7 +342,7 @@ static int elf_header_exclude_ranges(struct crash_elf_data *ced,
 	return ret;
 }
 
-static int prepare_elf64_ram_headers_callback(u64 start, u64 end, void *arg)
+static int prepare_elf64_ram_headers_callback(struct resource *res, void *arg)
 {
 	struct crash_elf_data *ced = arg;
 	Elf64_Ehdr *ehdr;
@@ -355,7 +355,7 @@ static int prepare_elf64_ram_headers_callback(u64 start, u64 end, void *arg)
 	ehdr = ced->ehdr;
 
 	/* Exclude unwanted mem ranges */
-	ret = elf_header_exclude_ranges(ced, start, end);
+	ret = elf_header_exclude_ranges(ced, res->start, res->end);
 	if (ret)
 		return ret;
 
@@ -518,14 +518,14 @@ static int add_e820_entry(struct boot_params *params, struct e820_entry *entry)
 	return 0;
 }
 
-static int memmap_entry_callback(u64 start, u64 end, void *arg)
+static int memmap_entry_callback(struct resource *res, void *arg)
 {
 	struct crash_memmap_data *cmd = arg;
 	struct boot_params *params = cmd->params;
 	struct e820_entry ei;
 
-	ei.addr = start;
-	ei.size = end - start + 1;
+	ei.addr = res->start;
+	ei.size = res->end - res->start + 1;
 	ei.type = cmd->type;
 	add_e820_entry(params, &ei);
 
@@ -619,12 +619,12 @@ int crash_setup_memmap_entries(struct kimage *image, struct boot_params *params)
 	return ret;
 }
 
-static int determine_backup_region(u64 start, u64 end, void *arg)
+static int determine_backup_region(struct resource *res, void *arg)
 {
 	struct kimage *image = arg;
 
-	image->arch.backup_src_start = start;
-	image->arch.backup_src_sz = end - start + 1;
+	image->arch.backup_src_start = res->start;
+	image->arch.backup_src_sz = res->end - res->start + 1;
 
 	/* Expecting only one range for backup region */
 	return 1;

arch/x86/kernel/pmem.c

@@ -7,7 +7,7 @@
 #include <linux/init.h>
 #include <linux/ioport.h>
 
-static int found(u64 start, u64 end, void *data)
+static int found(struct resource *res, void *data)
 {
 	return 1;
 }

include/linux/ioport.h

@@ -272,10 +272,10 @@ walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
 		void *arg, int (*func)(unsigned long, unsigned long, void *));
 extern int
 walk_system_ram_res(u64 start, u64 end, void *arg,
-		    int (*func)(u64, u64, void *));
+		    int (*func)(struct resource *, void *));
 extern int
 walk_iomem_res_desc(unsigned long desc, unsigned long flags, u64 start, u64 end,
-		    void *arg, int (*func)(u64, u64, void *));
+		    void *arg, int (*func)(struct resource *, void *));
 
 /* True if any part of r1 overlaps r2 */
 static inline bool resource_overlaps(struct resource *r1, struct resource *r2)

include/linux/kexec.h

@@ -160,7 +160,7 @@ struct kexec_buf {
 };
 
 int __weak arch_kexec_walk_mem(struct kexec_buf *kbuf,
-			       int (*func)(u64, u64, void *));
+			       int (*func)(struct resource *, void *));
 extern int kexec_add_buffer(struct kexec_buf *kbuf);
 int kexec_locate_mem_hole(struct kexec_buf *kbuf);
 #endif /* CONFIG_KEXEC_FILE */

kernel/kexec_file.c

@@ -406,9 +406,10 @@ static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end,
 	return 1;
 }
 
-static int locate_mem_hole_callback(u64 start, u64 end, void *arg)
+static int locate_mem_hole_callback(struct resource *res, void *arg)
 {
 	struct kexec_buf *kbuf = (struct kexec_buf *)arg;
+	u64 start = res->start, end = res->end;
 	unsigned long sz = end - start + 1;
 
 	/* Returning 0 will take to next memory range */
@@ -437,7 +438,7 @@ static int locate_mem_hole_callback(u64 start, u64 end, void *arg)
  * func returning non-zero, then zero will be returned.
  */
 int __weak arch_kexec_walk_mem(struct kexec_buf *kbuf,
-			       int (*func)(u64, u64, void *))
+			       int (*func)(struct resource *, void *))
 {
 	if (kbuf->image->type == KEXEC_TYPE_CRASH)
 		return walk_iomem_res_desc(crashk_res.desc,

kernel/resource.c

@@ -402,14 +402,15 @@ static int find_next_iomem_res(struct resource *res, unsigned long desc,
 
 static int __walk_iomem_res_desc(struct resource *res, unsigned long desc,
 				 bool first_level_children_only,
-				 void *arg, int (*func)(u64, u64, void *))
+				 void *arg,
+				 int (*func)(struct resource *, void *))
 {
 	u64 orig_end = res->end;
 	int ret = -1;
 
 	while ((res->start < res->end) &&
 	       !find_next_iomem_res(res, desc, first_level_children_only)) {
-		ret = (*func)(res->start, res->end, arg);
+		ret = (*func)(res, arg);
 		if (ret)
 			break;
 
@@ -435,7 +436,7 @@ static int __walk_iomem_res_desc(struct resource *res, unsigned long desc,
  * <linux/ioport.h> and set it in 'desc' of a target resource entry.
  */
 int walk_iomem_res_desc(unsigned long desc, unsigned long flags, u64 start,
-		u64 end, void *arg, int (*func)(u64, u64, void *))
+		u64 end, void *arg, int (*func)(struct resource *, void *))
 {
 	struct resource res;
 
@@ -454,7 +455,7 @@ int walk_iomem_res_desc(unsigned long desc, unsigned long flags, u64 start,
  * ranges.
  */
 int walk_system_ram_res(u64 start, u64 end, void *arg,
-				int (*func)(u64, u64, void *))
+				int (*func)(struct resource *, void *))
 {
 	struct resource res;