X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=blobdiff_plain;f=mm%2Fmadvise.c;h=42f4fd530e5a9289471a2595a7f45832b61c94b1;hp=74bf193eff04fdeea6c433675a3705adbeb3c0f1;hb=4cecd7e369e1b252db1d64451462221b362eed1c;hpb=555fedacc366c4aaf48270da2504dfa97c41a130

diff --git a/mm/madvise.c b/mm/madvise.c
index 74bf193eff04..42f4fd530e5a 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -13,6 +13,7 @@
 #include <linux/hugetlb.h>
 #include <linux/sched.h>
 #include <linux/ksm.h>
+#include <linux/file.h>
 
 /*
  * Any behaviour which results in changes to the vma->vm_flags needs to
@@ -127,6 +128,7 @@ static long madvise_willneed(struct vm_area_struct * vma,
 {
 	struct file *file = vma->vm_file;
 
+	*prev = vma;
 	if (!file)
 		return -EBADF;
 
@@ -135,7 +137,6 @@ static long madvise_willneed(struct vm_area_struct * vma,
 		return 0;
 	}
 
-	*prev = vma;
 	start = ((start - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
 	if (end > vma->vm_end)
 		end = vma->vm_end;
@@ -197,14 +198,16 @@ static long madvise_remove(struct vm_area_struct *vma,
 	struct address_space *mapping;
 	loff_t offset, endoff;
 	int error;
+	struct file *f;
 
 	*prev = NULL;	/* tell sys_madvise we drop mmap_sem */
 
 	if (vma->vm_flags & (VM_LOCKED|VM_NONLINEAR|VM_HUGETLB))
 		return -EINVAL;
 
-	if (!vma->vm_file || !vma->vm_file->f_mapping
-		|| !vma->vm_file->f_mapping->host) {
+	f = vma->vm_file;
+
+	if (!f || !f->f_mapping || !f->f_mapping->host) {
 			return -EINVAL;
 	}
 
@@ -218,13 +221,81 @@ static long madvise_remove(struct vm_area_struct *vma,
 	endoff = (loff_t)(end - vma->vm_start - 1)
 			+ ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
 
-	/* vmtruncate_range needs to take i_mutex */
+	/*
+	 * vmtruncate_range may need to take i_mutex.  We need to
+	 * explicitly grab a reference because the vma (and hence the
+	 * vma's reference to the file) can go away as soon as we drop
+	 * mmap_sem.
+	 */
+	get_file(f);
 	up_read(&current->mm->mmap_sem);
 	error = vmtruncate_range(mapping->host, offset, endoff);
+	fput(f);
 	down_read(&current->mm->mmap_sem);
 	return error;
 }
 
+#ifdef __arm__
+static long madvise_force_cache(struct vm_area_struct *vma,
+				struct vm_area_struct **prev,
+				unsigned long start, unsigned long end,
+				int tex_cb)
+{
+	struct mm_struct *mm = vma->vm_mm;
+	unsigned long addr, next_pgd, next_pmd;
+	spinlock_t *ptl;
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *pte;
+	u32 val;
+
+	*prev = vma;
+
+	if (mm == NULL)
+		return -EINVAL;
+
+	tex_cb &= 7;
+	vma->vm_page_prot = __pgprot_modify(vma->vm_page_prot,
+		L_PTE_MT_MASK, (tex_cb << 2));
+
+	addr = start;
+	pgd = pgd_offset(mm, addr);
+	flush_cache_range(vma, addr, end);
+	do {
+		next_pgd = pgd_addr_end(addr, end);
+		if (pgd_none_or_clear_bad(pgd))
+			continue;
+		pud = pud_offset(pgd, addr);
+		pmd = pmd_offset(pud, addr);
+		next_pmd = pmd_addr_end(addr, end);
+		if (pmd_trans_huge(*pmd)) {
+			val = pmd_val(*pmd);
+			val &= ~0x100c;
+			val |= (tex_cb << 10) & 0x1000;
+			val |= (tex_cb << 2)  & 0x000c;
+			set_pmd_at(mm, addr, pmd, __pmd(val));
+		}
+		else if (pmd_none_or_clear_bad(pmd))
+			continue;
+
+		pte = pte_offset_map_lock(mm, pmd, addr, &ptl);
+		do {
+			if (!pte_present(*pte))
+				continue;
+			val = pte_val(*pte);
+			val = (val & ~L_PTE_MT_MASK) | (tex_cb << 2);
+			set_pte_at(mm, addr, pte, __pte(val));
+		} while (pte++, addr += PAGE_SIZE, addr < next_pmd);
+		pte_unmap_unlock(pte - 1, ptl);
+
+	} while (pgd++, addr = next_pgd, addr < end);
+	flush_tlb_range(vma, start, end);
+
+	return 0;
+}
+#endif
+
 #ifdef CONFIG_MEMORY_FAILURE
 /*
  * Error injection support for memory error handling.
@@ -268,6 +339,11 @@ madvise_vma(struct vm_area_struct *vma, struct vm_area_struct **prev,
 		return madvise_willneed(vma, prev, start, end);
 	case MADV_DONTNEED:
 		return madvise_dontneed(vma, prev, start, end);
+#ifdef __arm__
+	case 0x2000 ... 0x2007:
+		return madvise_force_cache(vma, prev, start, end,
+			behavior & 7);
+#endif
 	default:
 		return madvise_behavior(vma, prev, start, end, behavior);
 	}
@@ -292,6 +368,9 @@ madvise_behavior_valid(int behavior)
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 	case MADV_HUGEPAGE:
 	case MADV_NOHUGEPAGE:
+#endif
+#ifdef __arm__
+	case 0x2000 ... 0x2007:
 #endif
 		return 1;