powerpc/mm: move warning from resize_hpt_for_hotplug()

resize_hpt_for_hotplug() reports a warning when it cannot
resize the hash page table ("Unable to resize hash page
table to target order") but in some cases it's not a problem
and can make user thinks something has not worked properly.

This patch moves the warning to arch_remove_memory() to
only report the problem when it is needed.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/include/asm/sparsemem.h

@@ -17,9 +17,9 @@ extern int create_section_mapping(unsigned long start, unsigned long end, int ni
 extern int remove_section_mapping(unsigned long start, unsigned long end);
 
 #ifdef CONFIG_PPC_BOOK3S_64
-extern void resize_hpt_for_hotplug(unsigned long new_mem_size);
+extern int resize_hpt_for_hotplug(unsigned long new_mem_size);
 #else
-static inline void resize_hpt_for_hotplug(unsigned long new_mem_size) { }
+static inline int resize_hpt_for_hotplug(unsigned long new_mem_size) { return 0; }
 #endif
 
 #ifdef CONFIG_NUMA

arch/powerpc/mm/hash_utils_64.c

@@ -755,12 +755,12 @@ static unsigned long __init htab_get_table_size(void)
 }
 
 #ifdef CONFIG_MEMORY_HOTPLUG
-void resize_hpt_for_hotplug(unsigned long new_mem_size)
+int resize_hpt_for_hotplug(unsigned long new_mem_size)
 {
 	unsigned target_hpt_shift;
 
 	if (!mmu_hash_ops.resize_hpt)
-		return;
+		return 0;
 
 	target_hpt_shift = htab_shift_for_mem_size(new_mem_size);
 
@@ -772,16 +772,11 @@ void resize_hpt_for_hotplug(unsigned long new_mem_size)
 	 * reduce unless the target shift is at least 2 below the
 	 * current shift
 	 */
-	if ((target_hpt_shift > ppc64_pft_size)
-	    || (target_hpt_shift < (ppc64_pft_size - 1))) {
-		int rc;
+	if (target_hpt_shift > ppc64_pft_size ||
+	    target_hpt_shift < ppc64_pft_size - 1)
+		return mmu_hash_ops.resize_hpt(target_hpt_shift);
 
-		rc = mmu_hash_ops.resize_hpt(target_hpt_shift);
-		if (rc && (rc != -ENODEV))
-			printk(KERN_WARNING
-			       "Unable to resize hash page table to target order %d: %d\n",
-			       target_hpt_shift, rc);
-	}
+	return 0;
 }
 
 int hash__create_section_mapping(unsigned long start, unsigned long end, int nid)

arch/powerpc/mm/mem.c

@@ -161,7 +161,8 @@ int __meminit arch_remove_memory(int nid, u64 start, u64 size,
 	 */
 	vm_unmap_aliases();
 
-	resize_hpt_for_hotplug(memblock_phys_mem_size());
+	if (resize_hpt_for_hotplug(memblock_phys_mem_size()) == -ENOSPC)
+		pr_warn("Hash collision while resizing HPT\n");
 
 	return ret;
 }

arch/powerpc/platforms/pseries/lpar.c

@@ -901,8 +901,10 @@ static int pseries_lpar_resize_hpt(unsigned long shift)
 		break;
 
 	case H_PARAMETER:
+		pr_warn("Invalid argument from H_RESIZE_HPT_PREPARE\n");
 		return -EINVAL;
 	case H_RESOURCE:
+		pr_warn("Operation not permitted from H_RESIZE_HPT_PREPARE\n");
 		return -EPERM;
 	default:
 		pr_warn("Unexpected error %d from H_RESIZE_HPT_PREPARE\n", rc);
@@ -918,7 +920,6 @@ static int pseries_lpar_resize_hpt(unsigned long shift)
 	if (rc != 0) {
 		switch (state.commit_rc) {
 		case H_PTEG_FULL:
-			pr_warn("Hash collision while resizing HPT\n");
 			return -ENOSPC;
 
 		default: