powerpc: Replace mem_init_done with slab_is_available()

We have a powerpc specific global called mem_init_done which is "set on
boot once kmalloc can be called".

But that's not *quite* true. We set it at the bottom of mem_init(), and
rely on the fact that mm_init() calls kmem_cache_init() immediately
after that, and nothing is running in parallel.

So replace it with the generic and 100% correct slab_is_available().

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

3 files changed, 6 insertions, 10 deletions

diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index b7285a5870f8..45fda71feb27 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -61,7 +61,6 @@
 #define CPU_FTR_NOEXECUTE       0
 #endif
 
-int mem_init_done;
 unsigned long long memory_limit;
 
 #ifdef CONFIG_HIGHMEM
@@ -377,8 +376,6 @@ void __init mem_init(void)
         pr_info("  * 0x%08lx..0x%08lx  : vmalloc & ioremap\n",
                 VMALLOC_START, VMALLOC_END);
 #endif /* CONFIG_PPC32 */
-
-        mem_init_done = 1;
 }
 
 void free_initmem(void)
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
index 70b4752af54f..7692d1bb1bc6 100644
--- a/arch/powerpc/mm/pgtable_32.c
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -107,9 +107,8 @@ void pgd_free(struct mm_struct *mm, pgd_t *pgd)
 __init_refok pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
 {
         pte_t *pte;
-        extern int mem_init_done;
 
-        if (mem_init_done) {
+        if (slab_is_available()) {
                 pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
         } else {
                 pte = __va(memblock_alloc(PAGE_SIZE, PAGE_SIZE));
@@ -216,7 +215,7 @@ __ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags,
          * Don't allow anybody to remap normal RAM that we're using.
          * mem_init() sets high_memory so only do the check after that.
          */
-        if (mem_init_done && (p < virt_to_phys(high_memory)) &&
+        if (slab_is_available() && (p < virt_to_phys(high_memory)) &&
             !(__allow_ioremap_reserved && memblock_is_region_reserved(p, size))) {
                 printk("__ioremap(): phys addr 0x%llx is RAM lr %ps\n",
                        (unsigned long long)p, __builtin_return_address(0));
@@ -244,7 +243,7 @@ __ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags,
         if ((v = p_mapped_by_tlbcam(p)))
                 goto out;
 
-        if (mem_init_done) {
+        if (slab_is_available()) {
                 struct vm_struct *area;
                 area = get_vm_area_caller(size, VM_IOREMAP, caller);
                 if (area == 0)
@@ -263,7 +262,7 @@ __ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags,
         for (i = 0; i < size && err == 0; i += PAGE_SIZE)
                 err = map_page(v+i, p+i, flags);
         if (err) {
-                if (mem_init_done)
+                if (slab_is_available())
                         vunmap((void *)v);
                 return NULL;
         }
diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c
index 3ac3a0a1edfb..59daa5eeec25 100644
--- a/arch/powerpc/mm/pgtable_64.c
+++ b/arch/powerpc/mm/pgtable_64.c
@@ -231,7 +231,7 @@ void __iomem * __ioremap_caller(phys_addr_t addr, unsigned long size,
         if ((size == 0) || (paligned == 0))
                 return NULL;
 
-        if (mem_init_done) {
+        if (slab_is_available()) {
                 struct vm_struct *area;
 
                 area = __get_vm_area_caller(size, VM_IOREMAP,
@@ -315,7 +315,7 @@ void __iounmap(volatile void __iomem *token)
 {
         void *addr;
 
-        if (!mem_init_done)
+        if (!slab_is_available())
                 return;
         
         addr = (void *) ((unsigned long __force)