mm/memory_hotplug: rename walk_memory_range() and pass start+size instead of pfns

walk_memory_range() was once used to iterate over sections.  Now, it
iterates over memory blocks.  Rename the function, fixup the
documentation.

Also, pass start+size instead of PFNs, which is what most callers
already have at hand.  (we'll rework link_mem_sections() most probably
soon)

Follow-up patches will rework, simplify, and move walk_memory_blocks()
to drivers/base/memory.c.

Note: walk_memory_blocks() only works correctly right now if the
start_pfn is aligned to a section start.  This is the case right now,
but we'll generalize the function in a follow up patch so the semantics
match the documentation.

[akpm@linux-foundation.org: remove unused variable]
Link: http://lkml.kernel.org/r/20190614100114.311-5-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Rashmica Gupta <rashmica.g@gmail.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Arun KS <arunks@codeaurora.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/powerpc/platforms/powernv/memtrace.c b/arch/powerpc/platforms/powernv/memtrace.c
index 5e53c1392d3b03ebc91bfc291532073ccb96b348..eb2e75dac369a4fc6e658b5088d408a375df1428 100644 (file)
--- a/arch/powerpc/platforms/powernv/memtrace.c
+++ b/arch/powerpc/platforms/powernv/memtrace.c
@@ -70,23 +70,23 @@ static int change_memblock_state(struct memory_block *mem, void *arg)
 /* called with device_hotplug_lock held */
 static bool memtrace_offline_pages(u32 nid, u64 start_pfn, u64 nr_pages)
 {
-       u64 end_pfn = start_pfn + nr_pages - 1;
+       const unsigned long start = PFN_PHYS(start_pfn);
+       const unsigned long size = PFN_PHYS(nr_pages);
 
-       if (walk_memory_range(start_pfn, end_pfn, NULL,
-           check_memblock_online))
+       if (walk_memory_blocks(start, size, NULL, check_memblock_online))
                return false;
 
-       walk_memory_range(start_pfn, end_pfn, (void *)MEM_GOING_OFFLINE,
-                         change_memblock_state);
+       walk_memory_blocks(start, size, (void *)MEM_GOING_OFFLINE,
+                          change_memblock_state);
 
        if (offline_pages(start_pfn, nr_pages)) {
-               walk_memory_range(start_pfn, end_pfn, (void *)MEM_ONLINE,
-                                 change_memblock_state);
+               walk_memory_blocks(start, size, (void *)MEM_ONLINE,
+                                  change_memblock_state);
                return false;
        }
 
-       walk_memory_range(start_pfn, end_pfn, (void *)MEM_OFFLINE,
-                         change_memblock_state);
+       walk_memory_blocks(start, size, (void *)MEM_OFFLINE,
+                          change_memblock_state);
 
 
        return true;
@@ -242,9 +242,8 @@ static int memtrace_online(void)
                 */
                if (!memhp_auto_online) {
                        lock_device_hotplug();
-                       walk_memory_range(PFN_DOWN(ent->start),
-                                         PFN_UP(ent->start + ent->size - 1),
-                                         NULL, online_mem_block);
+                       walk_memory_blocks(ent->start, ent->size, NULL,
+                                          online_mem_block);
                        unlock_device_hotplug();
                }
 

diff --git a/drivers/acpi/acpi_memhotplug.c b/drivers/acpi/acpi_memhotplug.c
index db013dc21c0240b897f7214dbb0a0e8390285118..e294f44a785046656379b574893061c6377b5beb 100644 (file)
--- a/drivers/acpi/acpi_memhotplug.c
+++ b/drivers/acpi/acpi_memhotplug.c
@@ -155,16 +155,6 @@ static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
        return 0;
 }
 
-static unsigned long acpi_meminfo_start_pfn(struct acpi_memory_info *info)
-{
-       return PFN_DOWN(info->start_addr);
-}
-
-static unsigned long acpi_meminfo_end_pfn(struct acpi_memory_info *info)
-{
-       return PFN_UP(info->start_addr + info->length-1);
-}
-
 static int acpi_bind_memblk(struct memory_block *mem, void *arg)
 {
        return acpi_bind_one(&mem->dev, arg);
@@ -173,9 +163,8 @@ static int acpi_bind_memblk(struct memory_block *mem, void *arg)
 static int acpi_bind_memory_blocks(struct acpi_memory_info *info,
                                   struct acpi_device *adev)
 {
-       return walk_memory_range(acpi_meminfo_start_pfn(info),
-                                acpi_meminfo_end_pfn(info), adev,
-                                acpi_bind_memblk);
+       return walk_memory_blocks(info->start_addr, info->length, adev,
+                                 acpi_bind_memblk);
 }
 
 static int acpi_unbind_memblk(struct memory_block *mem, void *arg)
@@ -186,8 +175,8 @@ static int acpi_unbind_memblk(struct memory_block *mem, void *arg)
 
 static void acpi_unbind_memory_blocks(struct acpi_memory_info *info)
 {
-       walk_memory_range(acpi_meminfo_start_pfn(info),
-                         acpi_meminfo_end_pfn(info), NULL, acpi_unbind_memblk);
+       walk_memory_blocks(info->start_addr, info->length, NULL,
+                          acpi_unbind_memblk);
 }
 
 static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)

diff --git a/drivers/base/node.c b/drivers/base/node.c
index 27391f1e8f609f8f15e2c66ea6580810bf1bf772..75b7e6f6535b5ac54351a1fd7a4c772ccada5e25 100644 (file)
--- a/drivers/base/node.c
+++ b/drivers/base/node.c
@@ -834,8 +834,9 @@ void unregister_memory_block_under_nodes(struct memory_block *mem_blk)
 
 int link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn)
 {
-       return walk_memory_range(start_pfn, end_pfn, (void *)&nid,
-                                       register_mem_sect_under_node);
+       return walk_memory_blocks(PFN_PHYS(start_pfn),
+                                 PFN_PHYS(end_pfn - start_pfn), (void *)&nid,
+                                 register_mem_sect_under_node);
 }
 
 #ifdef CONFIG_HUGETLBFS

diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index 79e0add6a597e35d7277db936cec096feb8603bf..d9fffc34949f0ba25a2d4d28d0ecdc160c1f8c0b 100644 (file)
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -340,7 +340,7 @@ static inline void __remove_memory(int nid, u64 start, u64 size) {}
 #endif /* CONFIG_MEMORY_HOTREMOVE */
 
 extern void __ref free_area_init_core_hotplug(int nid);
-extern int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
+extern int walk_memory_blocks(unsigned long start, unsigned long size,
                void *arg, int (*func)(struct memory_block *, void *));
 extern int __add_memory(int nid, u64 start, u64 size);
 extern int add_memory(int nid, u64 start, u64 size);

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index d1d0ceaaca882ef6dc5e26932706cc65004bf20f..b3ef84e408fade3b3900c8947511d9a32674406b 100644 (file)
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1124,8 +1124,7 @@ int __ref add_memory_resource(int nid, struct resource *res)
 
        /* online pages if requested */
        if (memhp_auto_online)
-               walk_memory_range(PFN_DOWN(start), PFN_UP(start + size - 1),
-                                 NULL, online_memory_block);
+               walk_memory_blocks(start, size, NULL, online_memory_block);
 
        return ret;
 error:
@@ -1663,20 +1662,24 @@ int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
 #endif /* CONFIG_MEMORY_HOTREMOVE */
 
 /**
- * walk_memory_range - walks through all mem sections in [start_pfn, end_pfn)
- * @start_pfn: start pfn of the memory range
- * @end_pfn: end pfn of the memory range
+ * walk_memory_blocks - walk through all present memory blocks overlapped
+ *                     by the range [start, start + size)
+ *
+ * @start: start address of the memory range
+ * @size: size of the memory range
  * @arg: argument passed to func
- * @func: callback for each memory section walked
+ * @func: callback for each memory block walked
  *
- * This function walks through all present mem sections in range
- * [start_pfn, end_pfn) and call func on each mem section.
+ * This function walks through all present memory blocks overlapped by the
+ * range [start, start + size), calling func on each memory block.
  *
  * Returns the return value of func.
  */
-int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
+int walk_memory_blocks(unsigned long start, unsigned long size,
                void *arg, int (*func)(struct memory_block *, void *))
 {
+       const unsigned long start_pfn = PFN_DOWN(start);
+       const unsigned long end_pfn = PFN_UP(start + size - 1);
        struct memory_block *mem = NULL;
        struct mem_section *section;
        unsigned long pfn, section_nr;
@@ -1822,8 +1825,7 @@ static int __ref try_remove_memory(int nid, u64 start, u64 size)
         * whether all memory blocks in question are offline and return error
         * if this is not the case.
         */
-       rc = walk_memory_range(PFN_DOWN(start), PFN_UP(start + size - 1), NULL,
-                              check_memblock_offlined_cb);
+       rc = walk_memory_blocks(start, size, NULL, check_memblock_offlined_cb);
        if (rc)
                goto done;