uprobes: Don't use loff_t for the valid virtual address

loff_t looks confusing when it is used for the virtual address.
Change map_info and install_breakpoint/remove_breakpoint paths
to use "unsigned long".

The patch doesn't change vma_address(), it can't return "long"
because it is used to verify the mapping. But probably this
needs some cleanups too.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Anton Arapov <anton@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154355.GA9622@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 7d5c78f063aed5c40fcfe88d2606c7a2d9ff204b..4df84b76dd4898dbff720d081e6af9e611da8f4a 100644 (file)
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -664,9 +664,8 @@ static int copy_insn(struct uprobe *uprobe, struct file *filp)
  */
 static int
 install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm,
-                       struct vm_area_struct *vma, loff_t vaddr)
+                       struct vm_area_struct *vma, unsigned long vaddr)
 {
-       unsigned long addr;
        int ret;
 
        /*
@@ -679,8 +678,6 @@ install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm,
        if (!uprobe->consumers)
                return -EEXIST;
 
-       addr = (unsigned long)vaddr;
-
        if (!(uprobe->flags & UPROBE_COPY_INSN)) {
                ret = copy_insn(uprobe, vma->vm_file);
                if (ret)
@@ -689,7 +686,7 @@ install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm,
                if (is_swbp_insn((uprobe_opcode_t *)uprobe->arch.insn))
                        return -ENOTSUPP;
 
-               ret = arch_uprobe_analyze_insn(&uprobe->arch, mm, addr);
+               ret = arch_uprobe_analyze_insn(&uprobe->arch, mm, vaddr);
                if (ret)
                        return ret;
 
@@ -709,7 +706,7 @@ install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm,
         * Hence increment before and decrement on failure.
         */
        atomic_inc(&mm->uprobes_state.count);
-       ret = set_swbp(&uprobe->arch, mm, addr);
+       ret = set_swbp(&uprobe->arch, mm, vaddr);
        if (ret)
                atomic_dec(&mm->uprobes_state.count);
 
@@ -717,9 +714,9 @@ install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm,
 }
 
 static void
-remove_breakpoint(struct uprobe *uprobe, struct mm_struct *mm, loff_t vaddr)
+remove_breakpoint(struct uprobe *uprobe, struct mm_struct *mm, unsigned long vaddr)
 {
-       if (!set_orig_insn(&uprobe->arch, mm, (unsigned long)vaddr, true))
+       if (!set_orig_insn(&uprobe->arch, mm, vaddr, true))
                atomic_dec(&mm->uprobes_state.count);
 }
 
@@ -743,7 +740,7 @@ static void delete_uprobe(struct uprobe *uprobe)
 struct map_info {
        struct map_info *next;
        struct mm_struct *mm;
-       loff_t vaddr;
+       unsigned long vaddr;
 };
 
 static inline struct map_info *free_map_info(struct map_info *info)
@@ -837,7 +834,6 @@ static int register_for_each_vma(struct uprobe *uprobe, bool is_register)
        while (info) {
                struct mm_struct *mm = info->mm;
                struct vm_area_struct *vma;
-               loff_t vaddr;
 
                if (err)
                        goto free;
@@ -847,9 +843,8 @@ static int register_for_each_vma(struct uprobe *uprobe, bool is_register)
                if (!vma || !valid_vma(vma, is_register))
                        goto unlock;
 
-               vaddr = vma_address(vma, uprobe->offset);
                if (vma->vm_file->f_mapping->host != uprobe->inode ||
-                                               vaddr != info->vaddr)
+                   vma_address(vma, uprobe->offset) != info->vaddr)
                        goto unlock;
 
                if (is_register) {
@@ -1055,10 +1050,8 @@ int uprobe_mmap(struct vm_area_struct *vma)
        count = 0;
 
        list_for_each_entry(uprobe, &tmp_list, pending_list) {
-               loff_t vaddr;
-
                if (!ret) {
-                       vaddr = vma_address(vma, uprobe->offset);
+                       loff_t vaddr = vma_address(vma, uprobe->offset);
 
                        if (vaddr < vma->vm_start || vaddr >= vma->vm_end) {
                                put_uprobe(uprobe);
@@ -1122,9 +1115,8 @@ void uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned lon
        build_probe_list(inode, &tmp_list);
 
        list_for_each_entry(uprobe, &tmp_list, pending_list) {
-               loff_t vaddr;
+               loff_t vaddr = vma_address(vma, uprobe->offset);
 
-               vaddr = vma_address(vma, uprobe->offset);
                if (vaddr >= start && vaddr < end) {
                        /*
                         * An unregister could have removed the probe before