acct: switch to __kernel_write()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

3 files changed, 13 insertions, 20 deletions

diff --git a/fs/internal.h b/fs/internal.h
index 465742407466..9a2edba87c2b 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -131,7 +131,6 @@ extern long prune_dcache_sb(struct super_block *sb, unsigned long nr_to_scan,
 /*
  * read_write.c
  */
-extern ssize_t __kernel_write(struct file *, const char *, size_t, loff_t *);
 extern int rw_verify_area(int, struct file *, const loff_t *, size_t);
 
 /*
diff --git a/include/linux/fs.h b/include/linux/fs.h
index e11d60cc867b..4b7d57cf7863 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2335,6 +2335,7 @@ extern int do_pipe_flags(int *, int);
 
 extern int kernel_read(struct file *, loff_t, char *, unsigned long);
 extern ssize_t kernel_write(struct file *, const char *, size_t, loff_t);
+extern ssize_t __kernel_write(struct file *, const char *, size_t, loff_t *);
 extern struct file * open_exec(const char *);
  
 /* fs/dcache.c -- generic fs support functions */
diff --git a/kernel/acct.c b/kernel/acct.c
index 807ebc5d8333..8082d9875d6b 100644
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -456,12 +456,16 @@ static void do_acct_process(struct bsd_acct_struct *acct,
 {
         struct pacct_struct *pacct = &current->signal->pacct;
         acct_t ac;
-        mm_segment_t fs;
         unsigned long flim;
         u64 elapsed, run_time;
         struct tty_struct *tty;
         const struct cred *orig_cred;
 
+        /*
+         * Accounting records are not subject to resource limits.
+         */
+        flim = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
+        current->signal->rlim[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY;
         /* Perform file operations on behalf of whoever enabled accounting */
         orig_cred = override_creds(file->f_cred);
 
@@ -536,25 +540,14 @@ static void do_acct_process(struct bsd_acct_struct *acct,
          * Get freeze protection. If the fs is frozen, just skip the write
          * as we could deadlock the system otherwise.
          */
-        if (!file_start_write_trylock(file))
-                goto out;
-        /*
-         * Kernel segment override to datasegment and write it
-         * to the accounting file.
-         */
-        fs = get_fs();
-        set_fs(KERNEL_DS);
-        /*
-         * Accounting records are not subject to resource limits.
-         */
-        flim = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
-        current->signal->rlim[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY;
-        file->f_op->write(file, (char *)&ac,
-                               sizeof(acct_t), &file->f_pos);
-        current->signal->rlim[RLIMIT_FSIZE].rlim_cur = flim;
-        set_fs(fs);
-        file_end_write(file);
+        if (file_start_write_trylock(file)) {
+                /* it's been opened O_APPEND, so position is irrelevant */
+                loff_t pos = 0;
+                __kernel_write(file, (char *)&ac, sizeof(acct_t), &pos);
+                file_end_write(file);
+        }
 out:
+        current->signal->rlim[RLIMIT_FSIZE].rlim_cur = flim;
         revert_creds(orig_cred);
 }