[PATCH] rcu: Mention rcu_bh in description of rcutorture's torture_type parameter
[linux-2.6.git] / kernel / acct.c
index 4168f63..0aad5ca 100644 (file)
  * a struct file opened for write. Fixed. 2/6/2000, AV.
  */
 
-#include <linux/config.h>
 #include <linux/mm.h>
 #include <linux/slab.h>
 #include <linux/acct.h>
+#include <linux/capability.h>
 #include <linux/file.h>
 #include <linux/tty.h>
 #include <linux/security.h>
@@ -54,6 +54,7 @@
 #include <linux/jiffies.h>
 #include <linux/times.h>
 #include <linux/syscalls.h>
+#include <linux/mount.h>
 #include <asm/uaccess.h>
 #include <asm/div64.h>
 #include <linux/blkdev.h> /* sector_div */
@@ -73,7 +74,7 @@ int acct_parm[3] = {4, 2, 30};
 /*
  * External references and all of the globals.
  */
-static void do_acct_process(long, struct file *);
+static void do_acct_process(struct file *);
 
 /*
  * This structure is used so that all the data protected by lock
@@ -116,7 +117,7 @@ static int check_free_space(struct file *file)
        spin_unlock(&acct_globals.lock);
 
        /* May block */
-       if (vfs_statfs(file->f_dentry->d_inode->i_sb, &sbuf))
+       if (vfs_statfs(file->f_dentry, &sbuf))
                return res;
        suspend = sbuf.f_blocks * SUSPEND;
        resume = sbuf.f_blocks * RESUME;
@@ -165,7 +166,7 @@ out:
 }
 
 /*
- * Close the old accouting file (if currently open) and then replace
+ * Close the old accounting file (if currently open) and then replace
  * it with file (if non-NULL).
  *
  * NOTE: acct_globals.lock MUST be held on entry and exit.
@@ -192,74 +193,113 @@ static void acct_file_reopen(struct file *file)
                add_timer(&acct_globals.timer);
        }
        if (old_acct) {
+               mnt_unpin(old_acct->f_vfsmnt);
                spin_unlock(&acct_globals.lock);
-               do_acct_process(0, old_acct);
+               do_acct_process(old_acct);
                filp_close(old_acct, NULL);
                spin_lock(&acct_globals.lock);
        }
 }
 
-/*
- *  sys_acct() is the only system call needed to implement process
- *  accounting. It takes the name of the file where accounting records
- *  should be written. If the filename is NULL, accounting will be
- *  shutdown.
- */
-asmlinkage long sys_acct(const char __user *name)
+static int acct_on(char *name)
 {
-       struct file *file = NULL;
-       char *tmp;
+       struct file *file;
        int error;
 
-       if (!capable(CAP_SYS_PACCT))
-               return -EPERM;
+       /* Difference from BSD - they don't do O_APPEND */
+       file = filp_open(name, O_WRONLY|O_APPEND|O_LARGEFILE, 0);
+       if (IS_ERR(file))
+               return PTR_ERR(file);
 
-       if (name) {
-               tmp = getname(name);
-               if (IS_ERR(tmp)) {
-                       return (PTR_ERR(tmp));
-               }
-               /* Difference from BSD - they don't do O_APPEND */
-               file = filp_open(tmp, O_WRONLY|O_APPEND, 0);
-               putname(tmp);
-               if (IS_ERR(file)) {
-                       return (PTR_ERR(file));
-               }
-               if (!S_ISREG(file->f_dentry->d_inode->i_mode)) {
-                       filp_close(file, NULL);
-                       return (-EACCES);
-               }
+       if (!S_ISREG(file->f_dentry->d_inode->i_mode)) {
+               filp_close(file, NULL);
+               return -EACCES;
+       }
 
-               if (!file->f_op->write) {
-                       filp_close(file, NULL);
-                       return (-EIO);
-               }
+       if (!file->f_op->write) {
+               filp_close(file, NULL);
+               return -EIO;
        }
 
        error = security_acct(file);
        if (error) {
-               if (file)
-                       filp_close(file, NULL);
+               filp_close(file, NULL);
                return error;
        }
 
        spin_lock(&acct_globals.lock);
+       mnt_pin(file->f_vfsmnt);
        acct_file_reopen(file);
        spin_unlock(&acct_globals.lock);
 
-       return (0);
+       mntput(file->f_vfsmnt); /* it's pinned, now give up active reference */
+
+       return 0;
 }
 
-/*
- * If the accouting is turned on for a file in the filesystem pointed
- * to by sb, turn accouting off.
+/**
+ * sys_acct - enable/disable process accounting
+ * @name: file name for accounting records or NULL to shutdown accounting
+ *
+ * Returns 0 for success or negative errno values for failure.
+ *
+ * sys_acct() is the only system call needed to implement process
+ * accounting. It takes the name of the file where accounting records
+ * should be written. If the filename is NULL, accounting will be
+ * shutdown.
+ */
+asmlinkage long sys_acct(const char __user *name)
+{
+       int error;
+
+       if (!capable(CAP_SYS_PACCT))
+               return -EPERM;
+
+       if (name) {
+               char *tmp = getname(name);
+               if (IS_ERR(tmp))
+                       return (PTR_ERR(tmp));
+               error = acct_on(tmp);
+               putname(tmp);
+       } else {
+               error = security_acct(NULL);
+               if (!error) {
+                       spin_lock(&acct_globals.lock);
+                       acct_file_reopen(NULL);
+                       spin_unlock(&acct_globals.lock);
+               }
+       }
+       return error;
+}
+
+/**
+ * acct_auto_close - turn off a filesystem's accounting if it is on
+ * @m: vfsmount being shut down
+ *
+ * If the accounting is turned on for a file in the subtree pointed to
+ * to by m, turn accounting off.  Done when m is about to die.
+ */
+void acct_auto_close_mnt(struct vfsmount *m)
+{
+       spin_lock(&acct_globals.lock);
+       if (acct_globals.file && acct_globals.file->f_vfsmnt == m)
+               acct_file_reopen(NULL);
+       spin_unlock(&acct_globals.lock);
+}
+
+/**
+ * acct_auto_close - turn off a filesystem's accounting if it is on
+ * @sb: super block for the filesystem
+ *
+ * If the accounting is turned on for a file in the filesystem pointed
+ * to by sb, turn accounting off.
  */
 void acct_auto_close(struct super_block *sb)
 {
        spin_lock(&acct_globals.lock);
        if (acct_globals.file &&
-           acct_globals.file->f_dentry->d_inode->i_sb == sb) {
-               acct_file_reopen((struct file *)NULL);
+           acct_globals.file->f_vfsmnt->mnt_sb == sb) {
+               acct_file_reopen(NULL);
        }
        spin_unlock(&acct_globals.lock);
 }
@@ -378,11 +418,11 @@ static u32 encode_float(u64 value)
 /*
  *  do_acct_process does all actual work. Caller holds the reference to file.
  */
-static void do_acct_process(long exitcode, struct file *file)
+static void do_acct_process(struct file *file)
 {
+       struct pacct_struct *pacct = &current->signal->pacct;
        acct_t ac;
        mm_segment_t fs;
-       unsigned long vsize;
        unsigned long flim;
        u64 elapsed;
        u64 run_time;
@@ -407,8 +447,8 @@ static void do_acct_process(long exitcode, struct file *file)
        /* calculate run_time in nsec*/
        do_posix_clock_monotonic_gettime(&uptime);
        run_time = (u64)uptime.tv_sec*NSEC_PER_SEC + uptime.tv_nsec;
-       run_time -= (u64)current->start_time.tv_sec*NSEC_PER_SEC
-                                       + current->start_time.tv_nsec;
+       run_time -= (u64)current->group_leader->start_time.tv_sec * NSEC_PER_SEC
+                      + current->group_leader->start_time.tv_nsec;
        /* convert nsec -> AHZ */
        elapsed = nsec_to_AHZ(run_time);
 #if ACCT_VERSION==3
@@ -427,12 +467,6 @@ static void do_acct_process(long exitcode, struct file *file)
 #endif
        do_div(elapsed, AHZ);
        ac.ac_btime = xtime.tv_sec - elapsed;
-       ac.ac_utime = encode_comp_t(jiffies_to_AHZ(
-                                           current->signal->utime +
-                                           current->group_leader->utime));
-       ac.ac_stime = encode_comp_t(jiffies_to_AHZ(
-                                           current->signal->stime +
-                                           current->group_leader->stime));
        /* we really need to bite the bullet and change layout */
        ac.ac_uid = current->uid;
        ac.ac_gid = current->gid;
@@ -449,42 +483,27 @@ static void do_acct_process(long exitcode, struct file *file)
        ac.ac_ppid = current->parent->tgid;
 #endif
 
-       read_lock(&tasklist_lock);      /* pin current->signal */
+       mutex_lock(&tty_mutex);
+       /* FIXME: Whoever is responsible for current->signal locking needs
+          to use the same locking all over the kernel and document it */
+       read_lock(&tasklist_lock);
        ac.ac_tty = current->signal->tty ?
                old_encode_dev(tty_devnum(current->signal->tty)) : 0;
        read_unlock(&tasklist_lock);
-
-       ac.ac_flag = 0;
-       if (current->flags & PF_FORKNOEXEC)
-               ac.ac_flag |= AFORK;
-       if (current->flags & PF_SUPERPRIV)
-               ac.ac_flag |= ASU;
-       if (current->flags & PF_DUMPCORE)
-               ac.ac_flag |= ACORE;
-       if (current->flags & PF_SIGNALED)
-               ac.ac_flag |= AXSIG;
-
-       vsize = 0;
-       if (current->mm) {
-               struct vm_area_struct *vma;
-               down_read(&current->mm->mmap_sem);
-               vma = current->mm->mmap;
-               while (vma) {
-                       vsize += vma->vm_end - vma->vm_start;
-                       vma = vma->vm_next;
-               }
-               up_read(&current->mm->mmap_sem);
-       }
-       vsize = vsize / 1024;
-       ac.ac_mem = encode_comp_t(vsize);
+       mutex_unlock(&tty_mutex);
+
+       spin_lock_irq(&current->sighand->siglock);
+       ac.ac_utime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_utime)));
+       ac.ac_stime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_stime)));
+       ac.ac_flag = pacct->ac_flag;
+       ac.ac_mem = encode_comp_t(pacct->ac_mem);
+       ac.ac_minflt = encode_comp_t(pacct->ac_minflt);
+       ac.ac_majflt = encode_comp_t(pacct->ac_majflt);
+       ac.ac_exitcode = pacct->ac_exitcode;
+       spin_unlock_irq(&current->sighand->siglock);
        ac.ac_io = encode_comp_t(0 /* current->io_usage */);    /* %% */
        ac.ac_rw = encode_comp_t(ac.ac_io / 1024);
-       ac.ac_minflt = encode_comp_t(current->signal->min_flt +
-                                    current->group_leader->min_flt);
-       ac.ac_majflt = encode_comp_t(current->signal->maj_flt +
-                                    current->group_leader->maj_flt);
        ac.ac_swaps = encode_comp_t(0);
-       ac.ac_exitcode = exitcode;
 
        /*
          * Kernel segment override to datasegment and write it
@@ -503,10 +522,65 @@ static void do_acct_process(long exitcode, struct file *file)
        set_fs(fs);
 }
 
-/*
+/**
+ * acct_init_pacct - initialize a new pacct_struct
+ * @pacct: per-process accounting info struct to initialize
+ */
+void acct_init_pacct(struct pacct_struct *pacct)
+{
+       memset(pacct, 0, sizeof(struct pacct_struct));
+       pacct->ac_utime = pacct->ac_stime = cputime_zero;
+}
+
+/**
+ * acct_collect - collect accounting information into pacct_struct
+ * @exitcode: task exit code
+ * @group_dead: not 0, if this thread is the last one in the process.
+ */
+void acct_collect(long exitcode, int group_dead)
+{
+       struct pacct_struct *pacct = &current->signal->pacct;
+       unsigned long vsize = 0;
+
+       if (group_dead && current->mm) {
+               struct vm_area_struct *vma;
+               down_read(&current->mm->mmap_sem);
+               vma = current->mm->mmap;
+               while (vma) {
+                       vsize += vma->vm_end - vma->vm_start;
+                       vma = vma->vm_next;
+               }
+               up_read(&current->mm->mmap_sem);
+       }
+
+       spin_lock_irq(&current->sighand->siglock);
+       if (group_dead)
+               pacct->ac_mem = vsize / 1024;
+       if (thread_group_leader(current)) {
+               pacct->ac_exitcode = exitcode;
+               if (current->flags & PF_FORKNOEXEC)
+                       pacct->ac_flag |= AFORK;
+       }
+       if (current->flags & PF_SUPERPRIV)
+               pacct->ac_flag |= ASU;
+       if (current->flags & PF_DUMPCORE)
+               pacct->ac_flag |= ACORE;
+       if (current->flags & PF_SIGNALED)
+               pacct->ac_flag |= AXSIG;
+       pacct->ac_utime = cputime_add(pacct->ac_utime, current->utime);
+       pacct->ac_stime = cputime_add(pacct->ac_stime, current->stime);
+       pacct->ac_minflt += current->min_flt;
+       pacct->ac_majflt += current->maj_flt;
+       spin_unlock_irq(&current->sighand->siglock);
+}
+
+/**
  * acct_process - now just a wrapper around do_acct_process
+ * @exitcode: task exit code
+ *
+ * handles process accounting for an exiting task
  */
-void acct_process(long exitcode)
+void acct_process(void)
 {
        struct file *file = NULL;
 
@@ -525,37 +599,6 @@ void acct_process(long exitcode)
        get_file(file);
        spin_unlock(&acct_globals.lock);
 
-       do_acct_process(exitcode, file);
+       do_acct_process(file);
        fput(file);
 }
-
-
-/*
- * acct_update_integrals
- *    -  update mm integral fields in task_struct
- */
-void acct_update_integrals(struct task_struct *tsk)
-{
-       if (likely(tsk->mm)) {
-               long delta = tsk->stime - tsk->acct_stimexpd;
-
-               if (delta == 0)
-                       return;
-               tsk->acct_stimexpd = tsk->stime;
-               tsk->acct_rss_mem1 += delta * get_mm_counter(tsk->mm, rss);
-               tsk->acct_vm_mem1 += delta * tsk->mm->total_vm;
-       }
-}
-
-/*
- * acct_clear_integrals
- *    - clear the mm integral fields in task_struct
- */
-void acct_clear_integrals(struct task_struct *tsk)
-{
-       if (tsk) {
-               tsk->acct_stimexpd = 0;
-               tsk->acct_rss_mem1 = 0;
-               tsk->acct_vm_mem1 = 0;
-       }
-}