Fedora kernel-2.6.17-1.2142_FC4 patched with stable patch-2.6.17.4-vs2.0.2-rc26.diff

[linux-2.6.git] / arch / i386 / mm / ioremap.c

diff --git a/arch/i386/mm/ioremap.c b/arch/i386/mm/ioremap.c
index ab54279..247fde7 100644 (file)
--- a/arch/i386/mm/ioremap.c
+++ b/arch/i386/mm/ioremap.c
@@ -11,6 +11,7 @@
 #include <linux/vmalloc.h>
 #include <linux/init.h>
 #include <linux/slab.h>
+#include <linux/module.h>
 #include <asm/io.h>
 #include <asm/fixmap.h>
 #include <asm/cacheflush.h>
@@ -27,7 +28,7 @@ static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
        unsigned long pfn;
 
        pfn = phys_addr >> PAGE_SHIFT;
-       pte = pte_alloc_kernel(&init_mm, pmd, addr);
+       pte = pte_alloc_kernel(pmd, addr);
        if (!pte)
                return -ENOMEM;
        do {
@@ -86,14 +87,12 @@ static int ioremap_page_range(unsigned long addr,
        flush_cache_all();
        phys_addr -= addr;
        pgd = pgd_offset_k(addr);
-       spin_lock(&init_mm.page_table_lock);
        do {
                next = pgd_addr_end(addr, end);
                err = ioremap_pud_range(pgd, addr, next, phys_addr+addr, flags);
                if (err)
                        break;
        } while (pgd++, addr = next, addr != end);
-       spin_unlock(&init_mm.page_table_lock);
        flush_tlb_all();
        return err;
 }
@@ -165,7 +164,7 @@ void __iomem * __ioremap(unsigned long phys_addr, unsigned long size, unsigned l
        }
        return (void __iomem *) (offset + (char __iomem *)addr);
 }
-
+EXPORT_SYMBOL(__ioremap);
 
 /**
  * ioremap_nocache     -   map bus memory into CPU space
@@ -222,11 +221,19 @@ void __iomem *ioremap_nocache (unsigned long phys_addr, unsigned long size)
 
        return p;                                       
 }
+EXPORT_SYMBOL(ioremap_nocache);
 
+/**
+ * iounmap - Free a IO remapping
+ * @addr: virtual address from ioremap_*
+ *
+ * Caller must ensure there is only one unmapping for the same pointer.
+ */
 void iounmap(volatile void __iomem *addr)
 {
-       struct vm_struct *p;
-       if ((void __force *) addr <= high_memory) 
+       struct vm_struct *p, *o;
+
+       if ((void __force *)addr <= high_memory)
                return;
 
        /*
@@ -238,23 +245,40 @@ void iounmap(volatile void __iomem *addr)
                        addr < phys_to_virt(ISA_END_ADDRESS))
                return;
 
-       write_lock(&vmlist_lock);
-       p = __remove_vm_area((void *) (PAGE_MASK & (unsigned long __force) addr));
-       if (!p) { 
+       addr = (volatile void __iomem *)(PAGE_MASK & (unsigned long __force)addr);
+
+       /* Use the vm area unlocked, assuming the caller
+          ensures there isn't another iounmap for the same address
+          in parallel. Reuse of the virtual address is prevented by
+          leaving it in the global lists until we're done with it.
+          cpa takes care of the direct mappings. */
+       read_lock(&vmlist_lock);
+       for (p = vmlist; p; p = p->next) {
+               if (p->addr == addr)
+                       break;
+       }
+       read_unlock(&vmlist_lock);
+
+       if (!p) {
                printk("iounmap: bad address %p\n", addr);
-               goto out_unlock;
+               dump_stack();
+               return;
        }
 
+       /* Reset the direct mapping. Can block */
        if ((p->flags >> 20) && p->phys_addr < virt_to_phys(high_memory) - 1) {
                change_page_attr(virt_to_page(__va(p->phys_addr)),
                                 p->size >> PAGE_SHIFT,
                                 PAGE_KERNEL);
                global_flush_tlb();
        } 
-out_unlock:
-       write_unlock(&vmlist_lock);
+
+       /* Finally remove it */
+       o = remove_vm_area((void *)addr);
+       BUG_ON(p != o || o == NULL);
        kfree(p); 
 }
+EXPORT_SYMBOL(iounmap);
 
 void __init *bt_ioremap(unsigned long phys_addr, unsigned long size)
 {