[PATCH] ppc64: Abolish ioremap_mm
Currently ppc64 has two mm_structs for the kernel, init_mm and also
ioremap_mm. The latter really isn't necessary: this patch abolishes it,
instead restricting vmallocs to the lower 1TB of the init_mm's range and
placing io mappings in the upper 1TB. This simplifies the code in a number
of places and eliminates an unecessary set of pagetables. It also tweaks
the unmap/free path a little, allowing us to remove the unmap_im_area() set
of page table walkers, replacing them with unmap_vm_area().
Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/ppc64/mm/init.c b/arch/ppc64/mm/init.c
index 4b42aff..6fa1e64 100644
--- a/arch/ppc64/mm/init.c
+++ b/arch/ppc64/mm/init.c
@@ -73,9 +73,6 @@
extern pgd_t swapper_pg_dir[];
extern struct task_struct *current_set[NR_CPUS];
-extern pgd_t ioremap_dir[];
-pgd_t * ioremap_pgd = (pgd_t *)&ioremap_dir;
-
unsigned long klimit = (unsigned long)_end;
unsigned long _SDR1=0;
@@ -137,69 +134,6 @@
#else
-static void unmap_im_area_pte(pmd_t *pmd, unsigned long addr,
- unsigned long end)
-{
- pte_t *pte;
-
- pte = pte_offset_kernel(pmd, addr);
- do {
- pte_t ptent = ptep_get_and_clear(&ioremap_mm, addr, pte);
- WARN_ON(!pte_none(ptent) && !pte_present(ptent));
- } while (pte++, addr += PAGE_SIZE, addr != end);
-}
-
-static inline void unmap_im_area_pmd(pud_t *pud, unsigned long addr,
- unsigned long end)
-{
- pmd_t *pmd;
- unsigned long next;
-
- pmd = pmd_offset(pud, addr);
- do {
- next = pmd_addr_end(addr, end);
- if (pmd_none_or_clear_bad(pmd))
- continue;
- unmap_im_area_pte(pmd, addr, next);
- } while (pmd++, addr = next, addr != end);
-}
-
-static inline void unmap_im_area_pud(pgd_t *pgd, unsigned long addr,
- unsigned long end)
-{
- pud_t *pud;
- unsigned long next;
-
- pud = pud_offset(pgd, addr);
- do {
- next = pud_addr_end(addr, end);
- if (pud_none_or_clear_bad(pud))
- continue;
- unmap_im_area_pmd(pud, addr, next);
- } while (pud++, addr = next, addr != end);
-}
-
-static void unmap_im_area(unsigned long addr, unsigned long end)
-{
- struct mm_struct *mm = &ioremap_mm;
- unsigned long next;
- pgd_t *pgd;
-
- spin_lock(&mm->page_table_lock);
-
- pgd = pgd_offset_i(addr);
- flush_cache_vunmap(addr, end);
- do {
- next = pgd_addr_end(addr, end);
- if (pgd_none_or_clear_bad(pgd))
- continue;
- unmap_im_area_pud(pgd, addr, next);
- } while (pgd++, addr = next, addr != end);
- flush_tlb_kernel_range(start, end);
-
- spin_unlock(&mm->page_table_lock);
-}
-
/*
* map_io_page currently only called by __ioremap
* map_io_page adds an entry to the ioremap page table
@@ -214,21 +148,21 @@
unsigned long vsid;
if (mem_init_done) {
- spin_lock(&ioremap_mm.page_table_lock);
- pgdp = pgd_offset_i(ea);
- pudp = pud_alloc(&ioremap_mm, pgdp, ea);
+ spin_lock(&init_mm.page_table_lock);
+ pgdp = pgd_offset_k(ea);
+ pudp = pud_alloc(&init_mm, pgdp, ea);
if (!pudp)
return -ENOMEM;
- pmdp = pmd_alloc(&ioremap_mm, pudp, ea);
+ pmdp = pmd_alloc(&init_mm, pudp, ea);
if (!pmdp)
return -ENOMEM;
- ptep = pte_alloc_kernel(&ioremap_mm, pmdp, ea);
+ ptep = pte_alloc_kernel(&init_mm, pmdp, ea);
if (!ptep)
return -ENOMEM;
pa = abs_to_phys(pa);
- set_pte_at(&ioremap_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT,
+ set_pte_at(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT,
__pgprot(flags)));
- spin_unlock(&ioremap_mm.page_table_lock);
+ spin_unlock(&init_mm.page_table_lock);
} else {
unsigned long va, vpn, hash, hpteg;
@@ -267,13 +201,9 @@
for (i = 0; i < size; i += PAGE_SIZE)
if (map_io_page(ea+i, pa+i, flags))
- goto failure;
+ return NULL;
return (void __iomem *) (ea + (addr & ~PAGE_MASK));
- failure:
- if (mem_init_done)
- unmap_im_area(ea, ea + size);
- return NULL;
}
@@ -381,19 +311,14 @@
*/
void iounmap(volatile void __iomem *token)
{
- unsigned long address, size;
void *addr;
if (!mem_init_done)
return;
addr = (void *) ((unsigned long __force) token & PAGE_MASK);
-
- if ((size = im_free(addr)) == 0)
- return;
- address = (unsigned long)addr;
- unmap_im_area(address, address + size);
+ im_free(addr);
}
static int iounmap_subset_regions(unsigned long addr, unsigned long size)