acct: switch to __kernel_write()

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

1 files changed, 12 insertions, 19 deletions

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);
 }