6 files changed, 494 insertions, 303 deletions

diff --git a/arch/s390/mm/Makefile b/arch/s390/mm/Makefile
index aa9a42b6e62d..8e09db1edbb9 100644
--- a/arch/s390/mm/Makefile
+++ b/arch/s390/mm/Makefile
@@ -2,6 +2,6 @@
 # Makefile for the linux s390-specific parts of the memory manager.
 #
 
-obj-y	 := init.o fault.o ioremap.o extmem.o mmap.o
+obj-y	 := init.o fault.o ioremap.o extmem.o mmap.o vmem.o
 obj-$(CONFIG_CMM) += cmm.o
 
diff --git a/arch/s390/mm/extmem.c b/arch/s390/mm/extmem.c
index 226275d5c4f6..775bf19e742b 100644
--- a/arch/s390/mm/extmem.c
+++ b/arch/s390/mm/extmem.c
@@ -14,12 +14,14 @@
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/bootmem.h>
+#include <linux/ctype.h>
 #include <asm/page.h>
+#include <asm/pgtable.h>
 #include <asm/ebcdic.h>
 #include <asm/errno.h>
 #include <asm/extmem.h>
 #include <asm/cpcmd.h>
-#include <linux/ctype.h>
+#include <asm/setup.h>
 
 #define DCSS_DEBUG	/* Debug messages on/off */
 
@@ -77,15 +79,11 @@ struct dcss_segment {
 	int segcnt;
 };
 
-static DEFINE_SPINLOCK(dcss_lock);
+static DEFINE_MUTEX(dcss_lock);
 static struct list_head dcss_list = LIST_HEAD_INIT(dcss_list);
 static char *segtype_string[] = { "SW", "EW", "SR", "ER", "SN", "EN", "SC",
 					"EW/EN-MIXED" };
 
-extern struct {
-	unsigned long addr, size, type;
-} memory_chunk[MEMORY_CHUNKS];
-
 /*
  * Create the 8 bytes, ebcdic VM segment name from
  * an ascii name.
@@ -117,7 +115,7 @@ segment_by_name (char *name)
 	struct list_head *l;
 	struct dcss_segment *tmp, *retval = NULL;
 
-	assert_spin_locked(&dcss_lock);
+	BUG_ON(!mutex_is_locked(&dcss_lock));
 	dcss_mkname (name, dcss_name);
 	list_for_each (l, &dcss_list) {
 		tmp = list_entry (l, struct dcss_segment, list);
@@ -241,65 +239,6 @@ query_segment_type (struct dcss_segment *seg)
 }
 
 /*
- * check if the given segment collides with guest storage.
- * returns 1 if this is the case, 0 if no collision was found
- */
-static int
-segment_overlaps_storage(struct dcss_segment *seg)
-{
-	int i;
-
-	for (i=0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
-		if (memory_chunk[i].type != 0)
-			continue;
-		if ((memory_chunk[i].addr >> 20) > (seg->end >> 20))
-			continue;
-		if (((memory_chunk[i].addr + memory_chunk[i].size - 1) >> 20)
-				< (seg->start_addr >> 20))
-			continue;
-		return 1;
-	}
-	return 0;
-}
-
-/*
- * check if segment collides with other segments that are currently loaded
- * returns 1 if this is the case, 0 if no collision was found
- */
-static int
-segment_overlaps_others (struct dcss_segment *seg)
-{
-	struct list_head *l;
-	struct dcss_segment *tmp;
-
-	assert_spin_locked(&dcss_lock);
-	list_for_each(l, &dcss_list) {
-		tmp = list_entry(l, struct dcss_segment, list);
-		if ((tmp->start_addr >> 20) > (seg->end >> 20))
-			continue;
-		if ((tmp->end >> 20) < (seg->start_addr >> 20))
-			continue;
-		if (seg == tmp)
-			continue;
-		return 1;
-	}
-	return 0;
-}
-
-/*
- * check if segment exceeds the kernel mapping range (detected or set via mem=)
- * returns 1 if this is the case, 0 if segment fits into the range
- */
-static inline int
-segment_exceeds_range (struct dcss_segment *seg)
-{
-	int seg_last_pfn = (seg->end) >> PAGE_SHIFT;
-	if (seg_last_pfn > max_pfn)
-		return 1;
-	return 0;
-}
-
-/*
  * get info about a segment
  * possible return values:
  * -ENOSYS  : we are not running on VM
@@ -344,24 +283,26 @@ __segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long
 	rc = query_segment_type (seg);
 	if (rc < 0)
 		goto out_free;
-	if (segment_exceeds_range(seg)) {
-		PRINT_WARN ("segment_load: not loading segment %s - exceeds"
-				" kernel mapping range\n",name);
-		rc = -ERANGE;
+
+	rc = add_shared_memory(seg->start_addr, seg->end - seg->start_addr + 1);
+
+	switch (rc) {
+	case 0:
+		break;
+	case -ENOSPC:
+		PRINT_WARN("segment_load: not loading segment %s - overlaps "
+			   "storage/segment\n", name);
 		goto out_free;
-	}
-	if (segment_overlaps_storage(seg)) {
-		PRINT_WARN ("segment_load: not loading segment %s - overlaps"
-				" storage\n",name);
-		rc = -ENOSPC;
+	case -ERANGE:
+		PRINT_WARN("segment_load: not loading segment %s - exceeds "
+			   "kernel mapping range\n", name);
 		goto out_free;
-	}
-	if (segment_overlaps_others(seg)) {
-		PRINT_WARN ("segment_load: not loading segment %s - overlaps"
-				" other segments\n",name);
-		rc = -EBUSY;
+	default:
+		PRINT_WARN("segment_load: not loading segment %s (rc: %d)\n",
+			   name, rc);
 		goto out_free;
 	}
+
 	if (do_nonshared)
 		dcss_command = DCSS_LOADNSR;
 	else
@@ -375,7 +316,7 @@ __segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long
 		rc = dcss_diag_translate_rc (seg->end);
 		dcss_diag(DCSS_PURGESEG, seg->dcss_name,
 				&seg->start_addr, &seg->end);
-		goto out_free;
+		goto out_shared;
 	}
 	seg->do_nonshared = do_nonshared;
 	atomic_set(&seg->ref_count, 1);
@@ -394,6 +335,8 @@ __segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long
 				(void*)seg->start_addr, (void*)seg->end,
 				segtype_string[seg->vm_segtype]);
 	goto out;
+ out_shared:
+	remove_shared_memory(seg->start_addr, seg->end - seg->start_addr + 1);
  out_free:
 	kfree(seg);
  out:
@@ -429,7 +372,7 @@ segment_load (char *name, int do_nonshared, unsigned long *addr,
 	if (!MACHINE_IS_VM)
 		return -ENOSYS;
 
-	spin_lock (&dcss_lock);
+	mutex_lock(&dcss_lock);
 	seg = segment_by_name (name);
 	if (seg == NULL)
 		rc = __segment_load (name, do_nonshared, addr, end);
@@ -444,7 +387,7 @@ segment_load (char *name, int do_nonshared, unsigned long *addr,
 			rc    = -EPERM;
 		}
 	}
-	spin_unlock (&dcss_lock);
+	mutex_unlock(&dcss_lock);
 	return rc;
 }
 
@@ -467,7 +410,7 @@ segment_modify_shared (char *name, int do_nonshared)
 	unsigned long dummy;
 	int dcss_command, rc, diag_cc;
 
-	spin_lock (&dcss_lock);
+	mutex_lock(&dcss_lock);
 	seg = segment_by_name (name);
 	if (seg == NULL) {
 		rc = -EINVAL;
@@ -508,7 +451,7 @@ segment_modify_shared (char *name, int do_nonshared)
 		  &dummy, &dummy);
 	kfree(seg);
  out_unlock:
-	spin_unlock(&dcss_lock);
+	mutex_unlock(&dcss_lock);
 	return rc;
 }
 
@@ -526,21 +469,21 @@ segment_unload(char *name)
 	if (!MACHINE_IS_VM)
 		return;
 
-	spin_lock(&dcss_lock);
+	mutex_lock(&dcss_lock);
 	seg = segment_by_name (name);
 	if (seg == NULL) {
 		PRINT_ERR ("could not find segment %s in segment_unload, "
 				"please report to linux390@de.ibm.com\n",name);
 		goto out_unlock;
 	}
-	if (atomic_dec_return(&seg->ref_count) == 0) {
-		list_del(&seg->list);
-		dcss_diag(DCSS_PURGESEG, seg->dcss_name,
-			  &dummy, &dummy);
-		kfree(seg);
-	}
+	if (atomic_dec_return(&seg->ref_count) != 0)
+		goto out_unlock;
+	remove_shared_memory(seg->start_addr, seg->end - seg->start_addr + 1);
+	list_del(&seg->list);
+	dcss_diag(DCSS_PURGESEG, seg->dcss_name, &dummy, &dummy);
+	kfree(seg);
 out_unlock:
-	spin_unlock(&dcss_lock);
+	mutex_unlock(&dcss_lock);
 }
 
 /*
@@ -559,12 +502,13 @@ segment_save(char *name)
 	if (!MACHINE_IS_VM)
 		return;
 
-	spin_lock(&dcss_lock);
+	mutex_lock(&dcss_lock);
 	seg = segment_by_name (name);
 
 	if (seg == NULL) {
-		PRINT_ERR ("could not find segment %s in segment_save, please report to linux390@de.ibm.com\n",name);
-		return;
+		PRINT_ERR("could not find segment %s in segment_save, please "
+			  "report to linux390@de.ibm.com\n", name);
+		goto out;
 	}
 
 	startpfn = seg->start_addr >> PAGE_SHIFT;
@@ -591,7 +535,7 @@ segment_save(char *name)
 		goto out;
 	}
 out:
-	spin_unlock(&dcss_lock);
+	mutex_unlock(&dcss_lock);
 }
 
 EXPORT_SYMBOL(segment_load);
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 1c323bbfda91..cd85e34d8703 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -31,6 +31,7 @@
 #include <asm/uaccess.h>
 #include <asm/pgtable.h>
 #include <asm/kdebug.h>
+#include <asm/s390_ext.h>
 
 #ifndef CONFIG_64BIT
 #define __FAIL_ADDR_MASK 0x7ffff000
@@ -394,6 +395,7 @@ void do_dat_exception(struct pt_regs *regs, unsigned long error_code)
 /*
  * 'pfault' pseudo page faults routines.
  */
+static ext_int_info_t ext_int_pfault;
 static int pfault_disable = 0;
 
 static int __init nopfault(char *str)
@@ -422,7 +424,7 @@ int pfault_init(void)
 		  __PF_RES_FIELD };
         int rc;
 
-	if (pfault_disable)
+	if (!MACHINE_IS_VM || pfault_disable)
 		return -1;
 	asm volatile(
 		"	diag	%1,%0,0x258\n"
@@ -440,7 +442,7 @@ void pfault_fini(void)
 	pfault_refbk_t refbk =
 	{ 0x258, 1, 5, 2, 0ULL, 0ULL, 0ULL, 0ULL };
 
-	if (pfault_disable)
+	if (!MACHINE_IS_VM || pfault_disable)
 		return;
 	__ctl_clear_bit(0,9);
 	asm volatile(
@@ -500,5 +502,25 @@ pfault_interrupt(__u16 error_code)
 			set_tsk_need_resched(tsk);
 	}
 }
-#endif
 
+void __init pfault_irq_init(void)
+{
+	if (!MACHINE_IS_VM)
+		return;
+
+	/*
+	 * Try to get pfault pseudo page faults going.
+	 */
+	if (register_early_external_interrupt(0x2603, pfault_interrupt,
+					      &ext_int_pfault) != 0)
+		panic("Couldn't request external interrupt 0x2603");
+
+	if (pfault_init() == 0)
+		return;
+
+	/* Tough luck, no pfault. */
+	pfault_disable = 1;
+	unregister_early_external_interrupt(0x2603, pfault_interrupt,
+					    &ext_int_pfault);
+}
+#endif
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index d99891718709..4bb21be3b007 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -24,6 +24,7 @@
 #include <linux/pagemap.h>
 #include <linux/bootmem.h>
 #include <linux/pfn.h>
+#include <linux/poison.h>
 
 #include <asm/processor.h>
 #include <asm/system.h>
@@ -69,6 +70,8 @@ void show_mem(void)
         printk("Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
         i = max_mapnr;
         while (i-- > 0) {
+		if (!pfn_valid(i))
+			continue;
 		page = pfn_to_page(i);
                 total++;
 		if (PageReserved(page))
@@ -84,65 +87,52 @@ void show_mem(void)
         printk("%d pages swap cached\n",cached);
 }
 
+static void __init setup_ro_region(void)
+{
+	pgd_t *pgd;
+	pmd_t *pmd;
+	pte_t *pte;
+	pte_t new_pte;
+	unsigned long address, end;
+
+	address = ((unsigned long)&__start_rodata) & PAGE_MASK;
+	end = PFN_ALIGN((unsigned long)&__end_rodata);
+
+	for (; address < end; address += PAGE_SIZE) {
+		pgd = pgd_offset_k(address);
+		pmd = pmd_offset(pgd, address);
+		pte = pte_offset_kernel(pmd, address);
+		new_pte = mk_pte_phys(address, __pgprot(_PAGE_RO));
+		set_pte(pte, new_pte);
+	}
+}
+
+extern void vmem_map_init(void);
+
 /*
  * paging_init() sets up the page tables
  */
-
-#ifndef CONFIG_64BIT
 void __init paging_init(void)
 {
-        pgd_t * pg_dir;
-        pte_t * pg_table;
-        pte_t   pte;
-	int     i;
-        unsigned long tmp;
-        unsigned long pfn = 0;
-        unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERNSEG_TABLE;
-        static const int ssm_mask = 0x04000000L;
-	unsigned long ro_start_pfn, ro_end_pfn;
+	pgd_t *pg_dir;
+	int i;
+	unsigned long pgdir_k;
+	static const int ssm_mask = 0x04000000L;
 	unsigned long max_zone_pfns[MAX_NR_ZONES];
 
-	ro_start_pfn = PFN_DOWN((unsigned long)&__start_rodata);
-	ro_end_pfn = PFN_UP((unsigned long)&__end_rodata);
-
-	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
-	max_zone_pfns[ZONE_DMA] = max_low_pfn;
-	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
-	free_area_init_nodes(max_zone_pfns);
-
-	/* unmap whole virtual address space */
+	pg_dir = swapper_pg_dir;
 	
-        pg_dir = swapper_pg_dir;
-
+#ifdef CONFIG_64BIT
+	pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERN_REGION_TABLE;
 	for (i = 0; i < PTRS_PER_PGD; i++)
-		pmd_clear((pmd_t *) pg_dir++);
-		
-	/*
-	 * map whole physical memory to virtual memory (identity mapping) 
-	 */
-
-        pg_dir = swapper_pg_dir;
-
-        while (pfn < max_low_pfn) {
-                /*
-                 * pg_table is physical at this point
-                 */
-		pg_table = (pte_t *) alloc_bootmem_pages(PAGE_SIZE);
-
-		pmd_populate_kernel(&init_mm, (pmd_t *) pg_dir, pg_table);
-                pg_dir++;
-
-                for (tmp = 0 ; tmp < PTRS_PER_PTE ; tmp++,pg_table++) {
-			if (pfn >= ro_start_pfn && pfn < ro_end_pfn)
-				pte = pfn_pte(pfn, __pgprot(_PAGE_RO));
-			else
-				pte = pfn_pte(pfn, PAGE_KERNEL);
-                        if (pfn >= max_low_pfn)
-				pte_val(pte) = _PAGE_TYPE_EMPTY;
-			set_pte(pg_table, pte);
-                        pfn++;
-                }
-        }
+		pgd_clear(pg_dir + i);
+#else
+	pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERNSEG_TABLE;
+	for (i = 0; i < PTRS_PER_PGD; i++)
+		pmd_clear((pmd_t *)(pg_dir + i));
+#endif
+	vmem_map_init();
+	setup_ro_region();
 
 	S390_lowcore.kernel_asce = pgdir_k;
 
@@ -152,82 +142,11 @@ void __init paging_init(void)
 	__ctl_load(pgdir_k, 13, 13);
 	__raw_local_irq_ssm(ssm_mask);
 
-        local_flush_tlb();
-}
-
-#else /* CONFIG_64BIT */
-
-void __init paging_init(void)
-{
-        pgd_t * pg_dir;
-	pmd_t * pm_dir;
-        pte_t * pt_dir;
-        pte_t   pte;
-	int     i,j,k;
-        unsigned long pfn = 0;
-        unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) |
-          _KERN_REGION_TABLE;
-	static const int ssm_mask = 0x04000000L;
-	unsigned long ro_start_pfn, ro_end_pfn;
-	unsigned long max_zone_pfns[MAX_NR_ZONES];
-
-	ro_start_pfn = PFN_DOWN((unsigned long)&__start_rodata);
-	ro_end_pfn = PFN_UP((unsigned long)&__end_rodata);
-
 	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
 	max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS);
 	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
 	free_area_init_nodes(max_zone_pfns);
-
-	/*
-	 * map whole physical memory to virtual memory (identity mapping) 
-	 */
-
-        pg_dir = swapper_pg_dir;
-	
-        for (i = 0 ; i < PTRS_PER_PGD ; i++,pg_dir++) {
-	
-                if (pfn >= max_low_pfn) {
-                        pgd_clear(pg_dir);
-                        continue;
-                }          
-        
-		pm_dir = (pmd_t *) alloc_bootmem_pages(PAGE_SIZE * 4);
-                pgd_populate(&init_mm, pg_dir, pm_dir);
-
-                for (j = 0 ; j < PTRS_PER_PMD ; j++,pm_dir++) {
-                        if (pfn >= max_low_pfn) {
-                                pmd_clear(pm_dir);
-                                continue; 
-                        }          
-                        
-			pt_dir = (pte_t *) alloc_bootmem_pages(PAGE_SIZE);
-                        pmd_populate_kernel(&init_mm, pm_dir, pt_dir);
-	
-                        for (k = 0 ; k < PTRS_PER_PTE ; k++,pt_dir++) {
-				if (pfn >= ro_start_pfn && pfn < ro_end_pfn)
-					pte = pfn_pte(pfn, __pgprot(_PAGE_RO));
-				else
-					pte = pfn_pte(pfn, PAGE_KERNEL);
-				if (pfn >= max_low_pfn)
-					pte_val(pte) = _PAGE_TYPE_EMPTY;
-                                set_pte(pt_dir, pte);
-                                pfn++;
-                        }
-                }
-        }
-
-	S390_lowcore.kernel_asce = pgdir_k;
-
-        /* enable virtual mapping in kernel mode */
-	__ctl_load(pgdir_k, 1, 1);
-	__ctl_load(pgdir_k, 7, 7);
-	__ctl_load(pgdir_k, 13, 13);
-	__raw_local_irq_ssm(ssm_mask);
-
-        local_flush_tlb();
 }
-#endif /* CONFIG_64BIT */
 
 void __init mem_init(void)
 {
@@ -257,6 +176,8 @@ void __init mem_init(void)
 	printk("Write protected kernel read-only data: %#lx - %#lx\n",
 	       (unsigned long)&__start_rodata,
 	       PFN_ALIGN((unsigned long)&__end_rodata) - 1);
+	printk("Virtual memmap size: %ldk\n",
+	       (max_pfn * sizeof(struct page)) >> 10);
 }
 
 void free_initmem(void)
@@ -267,6 +188,7 @@ void free_initmem(void)
         for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
 		ClearPageReserved(virt_to_page(addr));
 		init_page_count(virt_to_page(addr));
+		memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
 		free_page(addr);
 		totalram_pages++;
         }
diff --git a/arch/s390/mm/ioremap.c b/arch/s390/mm/ioremap.c
index 0f6e9ecbefe2..3d2100a4e209 100644
--- a/arch/s390/mm/ioremap.c
+++ b/arch/s390/mm/ioremap.c
@@ -15,87 +15,8 @@
 
 #include <linux/vmalloc.h>
 #include <linux/mm.h>
-#include <asm/io.h>
+#include <linux/io.h>
 #include <asm/pgalloc.h>
-#include <asm/cacheflush.h>
-#include <asm/tlbflush.h>
-
-static inline void remap_area_pte(pte_t * pte, unsigned long address, unsigned long size,
-        unsigned long phys_addr, unsigned long flags)
-{
-        unsigned long end;
-        unsigned long pfn;
-
-        address &= ~PMD_MASK;
-        end = address + size;
-        if (end > PMD_SIZE)
-                end = PMD_SIZE;
-	if (address >= end)
-		BUG();
-        pfn = phys_addr >> PAGE_SHIFT;
-        do {
-                if (!pte_none(*pte)) {
-                        printk("remap_area_pte: page already exists\n");
-			BUG();
-		}
-                set_pte(pte, pfn_pte(pfn, __pgprot(flags)));
-                address += PAGE_SIZE;
-                pfn++;
-                pte++;
-        } while (address && (address < end));
-}
-
-static inline int remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned long size,
-        unsigned long phys_addr, unsigned long flags)
-{
-	unsigned long end;
-
-	address &= ~PGDIR_MASK;
-	end = address + size;
-	if (end > PGDIR_SIZE)
-		end = PGDIR_SIZE;
-	phys_addr -= address;
-	if (address >= end)
-		BUG();
-	do {
-		pte_t * pte = pte_alloc_kernel(pmd, address);
-		if (!pte)
-			return -ENOMEM;
-		remap_area_pte(pte, address, end - address, address + phys_addr, flags);
-		address = (address + PMD_SIZE) & PMD_MASK;
-		pmd++;
-	} while (address && (address < end));
-	return 0;
-}
-
-static int remap_area_pages(unsigned long address, unsigned long phys_addr,
-				 unsigned long size, unsigned long flags)
-{
-	int error;
-	pgd_t * dir;
-	unsigned long end = address + size;
-
-	phys_addr -= address;
-	dir = pgd_offset(&init_mm, address);
-	flush_cache_all();
-	if (address >= end)
-		BUG();
-	do {
-		pmd_t *pmd;
-		pmd = pmd_alloc(&init_mm, dir, address);
-		error = -ENOMEM;
-		if (!pmd)
-			break;
-		if (remap_area_pmd(pmd, address, end - address,
-					 phys_addr + address, flags))
-			break;
-		error = 0;
-		address = (address + PGDIR_SIZE) & PGDIR_MASK;
-		dir++;
-	} while (address && (address < end));
-	flush_tlb_all();
-	return 0;
-}
 
 /*
  * Generic mapping function (not visible outside):
@@ -122,7 +43,8 @@ void * __ioremap(unsigned long phys_addr, unsigned long size, unsigned long flag
 	if (!area)
 		return NULL;
 	addr = area->addr;
-	if (remap_area_pages((unsigned long) addr, phys_addr, size, flags)) {
+	if (ioremap_page_range((unsigned long)addr, (unsigned long)addr + size,
+			       phys_addr, __pgprot(flags))) {
 		vfree(addr);
 		return NULL;
 	}
diff --git a/arch/s390/mm/vmem.c b/arch/s390/mm/vmem.c
new file mode 100644
index 000000000000..7f2944d3ec2a
--- /dev/null
+++ b/arch/s390/mm/vmem.c
@@ -0,0 +1,381 @@
+/*
+ *  arch/s390/mm/vmem.c
+ *
+ *    Copyright IBM Corp. 2006
+ *    Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
+ */
+
+#include <linux/bootmem.h>
+#include <linux/pfn.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/list.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+#include <asm/setup.h>
+#include <asm/tlbflush.h>
+
+unsigned long vmalloc_end;
+EXPORT_SYMBOL(vmalloc_end);
+
+static struct page *vmem_map;
+static DEFINE_MUTEX(vmem_mutex);
+
+struct memory_segment {
+	struct list_head list;
+	unsigned long start;
+	unsigned long size;
+};
+
+static LIST_HEAD(mem_segs);
+
+void memmap_init(unsigned long size, int nid, unsigned long zone,
+		 unsigned long start_pfn)
+{
+	struct page *start, *end;
+	struct page *map_start, *map_end;
+	int i;
+
+	start = pfn_to_page(start_pfn);
+	end = start + size;
+
+	for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
+		unsigned long cstart, cend;
+
+		cstart = PFN_DOWN(memory_chunk[i].addr);
+		cend = cstart + PFN_DOWN(memory_chunk[i].size);
+
+		map_start = mem_map + cstart;
+		map_end = mem_map + cend;
+
+		if (map_start < start)
+			map_start = start;
+		if (map_end > end)
+			map_end = end;
+
+		map_start -= ((unsigned long) map_start & (PAGE_SIZE - 1))
+			/ sizeof(struct page);
+		map_end += ((PFN_ALIGN((unsigned long) map_end)
+			     - (unsigned long) map_end)
+			    / sizeof(struct page));
+
+		if (map_start < map_end)
+			memmap_init_zone((unsigned long)(map_end - map_start),
+					 nid, zone, page_to_pfn(map_start));
+	}
+}
+
+static inline void *vmem_alloc_pages(unsigned int order)
+{
+	if (slab_is_available())
+		return (void *)__get_free_pages(GFP_KERNEL, order);
+	return alloc_bootmem_pages((1 << order) * PAGE_SIZE);
+}
+
+static inline pmd_t *vmem_pmd_alloc(void)
+{
+	pmd_t *pmd;
+	int i;
+
+	pmd = vmem_alloc_pages(PMD_ALLOC_ORDER);
+	if (!pmd)
+		return NULL;
+	for (i = 0; i < PTRS_PER_PMD; i++)
+		pmd_clear(pmd + i);
+	return pmd;
+}
+
+static inline pte_t *vmem_pte_alloc(void)
+{
+	pte_t *pte;
+	pte_t empty_pte;
+	int i;
+
+	pte = vmem_alloc_pages(PTE_ALLOC_ORDER);
+	if (!pte)
+		return NULL;
+	pte_val(empty_pte) = _PAGE_TYPE_EMPTY;
+	for (i = 0; i < PTRS_PER_PTE; i++)
+		set_pte(pte + i, empty_pte);
+	return pte;
+}
+
+/*
+ * Add a physical memory range to the 1:1 mapping.
+ */
+static int vmem_add_range(unsigned long start, unsigned long size)
+{
+	unsigned long address;
+	pgd_t *pg_dir;
+	pmd_t *pm_dir;
+	pte_t *pt_dir;
+	pte_t  pte;
+	int ret = -ENOMEM;
+
+	for (address = start; address < start + size; address += PAGE_SIZE) {
+		pg_dir = pgd_offset_k(address);
+		if (pgd_none(*pg_dir)) {
+			pm_dir = vmem_pmd_alloc();
+			if (!pm_dir)
+				goto out;
+			pgd_populate(&init_mm, pg_dir, pm_dir);
+		}
+
+		pm_dir = pmd_offset(pg_dir, address);
+		if (pmd_none(*pm_dir)) {
+			pt_dir = vmem_pte_alloc();
+			if (!pt_dir)
+				goto out;
+			pmd_populate_kernel(&init_mm, pm_dir, pt_dir);
+		}
+
+		pt_dir = pte_offset_kernel(pm_dir, address);
+		pte = pfn_pte(address >> PAGE_SHIFT, PAGE_KERNEL);
+		set_pte(pt_dir, pte);
+	}
+	ret = 0;
+out:
+	flush_tlb_kernel_range(start, start + size);
+	return ret;
+}
+
+/*
+ * Remove a physical memory range from the 1:1 mapping.
+ * Currently only invalidates page table entries.
+ */
+static void vmem_remove_range(unsigned long start, unsigned long size)
+{
+	unsigned long address;
+	pgd_t *pg_dir;
+	pmd_t *pm_dir;
+	pte_t *pt_dir;
+	pte_t  pte;
+
+	pte_val(pte) = _PAGE_TYPE_EMPTY;
+	for (address = start; address < start + size; address += PAGE_SIZE) {
+		pg_dir = pgd_offset_k(address);
+		if (pgd_none(*pg_dir))
+			continue;
+		pm_dir = pmd_offset(pg_dir, address);
+		if (pmd_none(*pm_dir))
+			continue;
+		pt_dir = pte_offset_kernel(pm_dir, address);
+		set_pte(pt_dir, pte);
+	}
+	flush_tlb_kernel_range(start, start + size);
+}
+
+/*
+ * Add a backed mem_map array to the virtual mem_map array.
+ */
+static int vmem_add_mem_map(unsigned long start, unsigned long size)
+{
+	unsigned long address, start_addr, end_addr;
+	struct page *map_start, *map_end;
+	pgd_t *pg_dir;
+	pmd_t *pm_dir;
+	pte_t *pt_dir;
+	pte_t  pte;
+	int ret = -ENOMEM;
+
+	map_start = vmem_map + PFN_DOWN(start);
+	map_end	= vmem_map + PFN_DOWN(start + size);
+
+	start_addr = (unsigned long) map_start & PAGE_MASK;
+	end_addr = PFN_ALIGN((unsigned long) map_end);
+
+	for (address = start_addr; address < end_addr; address += PAGE_SIZE) {
+		pg_dir = pgd_offset_k(address);
+		if (pgd_none(*pg_dir)) {
+			pm_dir = vmem_pmd_alloc();
+			if (!pm_dir)
+				goto out;
+			pgd_populate(&init_mm, pg_dir, pm_dir);
+		}
+
+		pm_dir = pmd_offset(pg_dir, address);
+		if (pmd_none(*pm_dir)) {
+			pt_dir = vmem_pte_alloc();
+			if (!pt_dir)
+				goto out;
+			pmd_populate_kernel(&init_mm, pm_dir, pt_dir);
+		}
+
+		pt_dir = pte_offset_kernel(pm_dir, address);
+		if (pte_none(*pt_dir)) {
+			unsigned long new_page;
+
+			new_page =__pa(vmem_alloc_pages(0));
+			if (!new_page)
+				goto out;
+			pte = pfn_pte(new_page >> PAGE_SHIFT, PAGE_KERNEL);
+			set_pte(pt_dir, pte);
+		}
+	}
+	ret = 0;
+out:
+	flush_tlb_kernel_range(start_addr, end_addr);
+	return ret;
+}
+
+static int vmem_add_mem(unsigned long start, unsigned long size)
+{
+	int ret;
+
+	ret = vmem_add_range(start, size);
+	if (ret)
+		return ret;
+	return vmem_add_mem_map(start, size);
+}
+
+/*
+ * Add memory segment to the segment list if it doesn't overlap with
+ * an already present segment.
+ */
+static int insert_memory_segment(struct memory_segment *seg)
+{
+	struct memory_segment *tmp;
+
+	if (PFN_DOWN(seg->start + seg->size) > max_pfn ||
+	    seg->start + seg->size < seg->start)
+		return -ERANGE;
+
+	list_for_each_entry(tmp, &mem_segs, list) {
+		if (seg->start >= tmp->start + tmp->size)
+			continue;
+		if (seg->start + seg->size <= tmp->start)
+			continue;
+		return -ENOSPC;
+	}
+	list_add(&seg->list, &mem_segs);
+	return 0;
+}
+
+/*
+ * Remove memory segment from the segment list.
+ */
+static void remove_memory_segment(struct memory_segment *seg)
+{
+	list_del(&seg->list);
+}
+
+static void __remove_shared_memory(struct memory_segment *seg)
+{
+	remove_memory_segment(seg);
+	vmem_remove_range(seg->start, seg->size);
+}
+
+int remove_shared_memory(unsigned long start, unsigned long size)
+{
+	struct memory_segment *seg;
+	int ret;
+
+	mutex_lock(&vmem_mutex);
+
+	ret = -ENOENT;
+	list_for_each_entry(seg, &mem_segs, list) {
+		if (seg->start == start && seg->size == size)
+			break;
+	}
+
+	if (seg->start != start || seg->size != size)
+		goto out;
+
+	ret = 0;
+	__remove_shared_memory(seg);
+	kfree(seg);
+out:
+	mutex_unlock(&vmem_mutex);
+	return ret;
+}
+
+int add_shared_memory(unsigned long start, unsigned long size)
+{
+	struct memory_segment *seg;
+	struct page *page;
+	unsigned long pfn, num_pfn, end_pfn;
+	int ret;
+
+	mutex_lock(&vmem_mutex);
+	ret = -ENOMEM;
+	seg = kzalloc(sizeof(*seg), GFP_KERNEL);
+	if (!seg)
+		goto out;
+	seg->start = start;
+	seg->size = size;
+
+	ret = insert_memory_segment(seg);
+	if (ret)
+		goto out_free;
+
+	ret = vmem_add_mem(start, size);
+	if (ret)
+		goto out_remove;
+
+	pfn = PFN_DOWN(start);
+	num_pfn = PFN_DOWN(size);
+	end_pfn = pfn + num_pfn;
+
+	page = pfn_to_page(pfn);
+	memset(page, 0, num_pfn * sizeof(struct page));
+
+	for (; pfn < end_pfn; pfn++) {
+		page = pfn_to_page(pfn);
+		init_page_count(page);
+		reset_page_mapcount(page);
+		SetPageReserved(page);
+		INIT_LIST_HEAD(&page->lru);
+	}
+	goto out;
+
+out_remove:
+	__remove_shared_memory(seg);
+out_free:
+	kfree(seg);
+out:
+	mutex_unlock(&vmem_mutex);
+	return ret;
+}
+
+/*
+ * map whole physical memory to virtual memory (identity mapping)
+ */
+void __init vmem_map_init(void)
+{
+	unsigned long map_size;
+	int i;
+
+	map_size = ALIGN(max_low_pfn, MAX_ORDER_NR_PAGES) * sizeof(struct page);
+	vmalloc_end = PFN_ALIGN(VMALLOC_END_INIT) - PFN_ALIGN(map_size);
+	vmem_map = (struct page *) vmalloc_end;
+	NODE_DATA(0)->node_mem_map = vmem_map;
+
+	for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++)
+		vmem_add_mem(memory_chunk[i].addr, memory_chunk[i].size);
+}
+
+/*
+ * Convert memory chunk array to a memory segment list so there is a single
+ * list that contains both r/w memory and shared memory segments.
+ */
+static int __init vmem_convert_memory_chunk(void)
+{
+	struct memory_segment *seg;
+	int i;
+
+	mutex_lock(&vmem_mutex);
+	for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
+		if (!memory_chunk[i].size)
+			continue;
+		seg = kzalloc(sizeof(*seg), GFP_KERNEL);
+		if (!seg)
+			panic("Out of memory...\n");
+		seg->start = memory_chunk[i].addr;
+		seg->size = memory_chunk[i].size;
+		insert_memory_segment(seg);
+	}
+	mutex_unlock(&vmem_mutex);
+	return 0;
+}
+
+core_initcall(vmem_convert_memory_chunk);