Merge master.kernel.org:/home/rmk/linux-2.6-arm-smp

[linux-2.6-omap-h63xx.git] / fs / proc / base.c

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 73b1e94171b7bc6cc01de6335f31f523c62bb3f4..23db452ab428c9896a96aad29217100e67aeb78a 100644 (file)
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -62,6 +62,7 @@
 #include <linux/namespace.h>
 #include <linux/mm.h>
 #include <linux/smp_lock.h>
+#include <linux/rcupdate.h>
 #include <linux/kallsyms.h>
 #include <linux/mount.h>
 #include <linux/security.h>
@@ -119,7 +120,6 @@ enum pid_directory_inos {
 #ifdef CONFIG_AUDITSYSCALL
        PROC_TGID_LOGINUID,
 #endif
-       PROC_TGID_FD_DIR,
        PROC_TGID_OOM_SCORE,
        PROC_TGID_OOM_ADJUST,
        PROC_TID_INO,
@@ -158,9 +158,11 @@ enum pid_directory_inos {
 #ifdef CONFIG_AUDITSYSCALL
        PROC_TID_LOGINUID,
 #endif
-       PROC_TID_FD_DIR = 0x8000,       /* 0x8000-0xffff */
        PROC_TID_OOM_SCORE,
        PROC_TID_OOM_ADJUST,
+
+       /* Add new entries before this */
+       PROC_TID_FD_DIR = 0x8000,       /* 0x8000-0xffff */
 };
 
 struct pid_entry {
@@ -282,16 +284,16 @@ static int proc_fd_link(struct inode *inode, struct dentry **dentry, struct vfsm
 
        files = get_files_struct(task);
        if (files) {
-               spin_lock(&files->file_lock);
+               rcu_read_lock();
                file = fcheck_files(files, fd);
                if (file) {
                        *mnt = mntget(file->f_vfsmnt);
                        *dentry = dget(file->f_dentry);
-                       spin_unlock(&files->file_lock);
+                       rcu_read_unlock();
                        put_files_struct(files);
                        return 0;
                }
-               spin_unlock(&files->file_lock);
+               rcu_read_unlock();
                put_files_struct(files);
        }
        return -ENOENT;
@@ -345,33 +347,6 @@ static int proc_root_link(struct inode *inode, struct dentry **dentry, struct vf
         (task->state == TASK_STOPPED || task->state == TASK_TRACED) && \
         security_ptrace(current,task) == 0))
 
-static int may_ptrace_attach(struct task_struct *task)
-{
-       int retval = 0;
-
-       task_lock(task);
-
-       if (!task->mm)
-               goto out;
-       if (((current->uid != task->euid) ||
-            (current->uid != task->suid) ||
-            (current->uid != task->uid) ||
-            (current->gid != task->egid) ||
-            (current->gid != task->sgid) ||
-            (current->gid != task->gid)) && !capable(CAP_SYS_PTRACE))
-               goto out;
-       rmb();
-       if (task->mm->dumpable != 1 && !capable(CAP_SYS_PTRACE))
-               goto out;
-       if (security_ptrace(current, task))
-               goto out;
-
-       retval = 1;
-out:
-       task_unlock(task);
-       return retval;
-}
-
 static int proc_pid_environ(struct task_struct *task, char * buffer)
 {
        int res = 0;
@@ -381,7 +356,7 @@ static int proc_pid_environ(struct task_struct *task, char * buffer)
                if (len > PAGE_SIZE)
                        len = PAGE_SIZE;
                res = access_process_vm(task, mm->env_start, buffer, len, 0);
-               if (!may_ptrace_attach(task))
+               if (!ptrace_may_attach(task))
                        res = -ESRCH;
                mmput(mm);
        }
@@ -684,7 +659,7 @@ static ssize_t mem_read(struct file * file, char __user * buf,
        int ret = -ESRCH;
        struct mm_struct *mm;
 
-       if (!MAY_PTRACE(task) || !may_ptrace_attach(task))
+       if (!MAY_PTRACE(task) || !ptrace_may_attach(task))
                goto out;
 
        ret = -ENOMEM;
@@ -710,7 +685,7 @@ static ssize_t mem_read(struct file * file, char __user * buf,
 
                this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
                retval = access_process_vm(task, src, page, this_len, 0);
-               if (!retval || !MAY_PTRACE(task) || !may_ptrace_attach(task)) {
+               if (!retval || !MAY_PTRACE(task) || !ptrace_may_attach(task)) {
                        if (!ret)
                                ret = -EIO;
                        break;
@@ -748,7 +723,7 @@ static ssize_t mem_write(struct file * file, const char * buf,
        struct task_struct *task = proc_task(file->f_dentry->d_inode);
        unsigned long dst = *ppos;
 
-       if (!MAY_PTRACE(task) || !may_ptrace_attach(task))
+       if (!MAY_PTRACE(task) || !ptrace_may_attach(task))
                return -ESRCH;
 
        page = (char *)__get_free_page(GFP_USER);
@@ -1065,6 +1040,7 @@ static int proc_readfd(struct file * filp, void * dirent, filldir_t filldir)
        int retval;
        char buf[NUMBUF];
        struct files_struct * files;
+       struct fdtable *fdt;
 
        retval = -ENOENT;
        if (!pid_alive(p))
@@ -1087,15 +1063,16 @@ static int proc_readfd(struct file * filp, void * dirent, filldir_t filldir)
                        files = get_files_struct(p);
                        if (!files)
                                goto out;
-                       spin_lock(&files->file_lock);
+                       rcu_read_lock();
+                       fdt = files_fdtable(files);
                        for (fd = filp->f_pos-2;
-                            fd < files->max_fds;
+                            fd < fdt->max_fds;
                             fd++, filp->f_pos++) {
                                unsigned int i,j;
 
                                if (!fcheck_files(files, fd))
                                        continue;
-                               spin_unlock(&files->file_lock);
+                               rcu_read_unlock();
 
                                j = NUMBUF;
                                i = fd;
@@ -1107,12 +1084,12 @@ static int proc_readfd(struct file * filp, void * dirent, filldir_t filldir)
 
                                ino = fake_ino(tid, PROC_TID_FD_DIR + fd);
                                if (filldir(dirent, buf+j, NUMBUF-j, fd+2, ino, DT_LNK) < 0) {
-                                       spin_lock(&files->file_lock);
+                                       rcu_read_lock();
                                        break;
                                }
-                               spin_lock(&files->file_lock);
+                               rcu_read_lock();
                        }
-                       spin_unlock(&files->file_lock);
+                       rcu_read_unlock();
                        put_files_struct(files);
        }
 out:
@@ -1287,9 +1264,9 @@ static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
 
        files = get_files_struct(task);
        if (files) {
-               spin_lock(&files->file_lock);
+               rcu_read_lock();
                if (fcheck_files(files, fd)) {
-                       spin_unlock(&files->file_lock);
+                       rcu_read_unlock();
                        put_files_struct(files);
                        if (task_dumpable(task)) {
                                inode->i_uid = task->euid;
@@ -1301,7 +1278,7 @@ static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
                        security_task_to_inode(task, inode);
                        return 1;
                }
-               spin_unlock(&files->file_lock);
+               rcu_read_unlock();
                put_files_struct(files);
        }
        d_drop(dentry);
@@ -1393,7 +1370,7 @@ static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry,
        if (!files)
                goto out_unlock;
        inode->i_mode = S_IFLNK;
-       spin_lock(&files->file_lock);
+       rcu_read_lock();
        file = fcheck_files(files, fd);
        if (!file)
                goto out_unlock2;
@@ -1401,7 +1378,7 @@ static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry,
                inode->i_mode |= S_IRUSR | S_IXUSR;
        if (file->f_mode & 2)
                inode->i_mode |= S_IWUSR | S_IXUSR;
-       spin_unlock(&files->file_lock);
+       rcu_read_unlock();
        put_files_struct(files);
        inode->i_op = &proc_pid_link_inode_operations;
        inode->i_size = 64;
@@ -1411,7 +1388,7 @@ static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry,
        return NULL;
 
 out_unlock2:
-       spin_unlock(&files->file_lock);
+       rcu_read_unlock();
        put_files_struct(files);
 out_unlock:
        iput(inode);