1 files changed, 74 insertions, 107 deletions

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 2d696b0c93bf..043c83cb51f9 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -105,7 +105,7 @@
  */
 
 struct pid_entry {
-        char *name;
+        const char *name;
         int len;
         umode_t mode;
         const struct inode_operations *iop;
@@ -130,10 +130,6 @@ struct pid_entry {
                 { .proc_get_link = get_link } )
 #define REG(NAME, MODE, fops)                           \
         NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
-#define INF(NAME, MODE, read)                           \
-        NOD(NAME, (S_IFREG|(MODE)),                     \
-                NULL, &proc_info_file_operations,       \
-                { .proc_read = read } )
 #define ONE(NAME, MODE, show)                           \
         NOD(NAME, (S_IFREG|(MODE)),                     \
                 NULL, &proc_single_file_operations,     \
@@ -200,27 +196,32 @@ static int proc_root_link(struct dentry *dentry, struct path *path)
         return result;
 }
 
-static int proc_pid_cmdline(struct task_struct *task, char *buffer)
+static int proc_pid_cmdline(struct seq_file *m, struct pid_namespace *ns,
+                            struct pid *pid, struct task_struct *task)
 {
-        return get_cmdline(task, buffer, PAGE_SIZE);
+        /*
+         * Rely on struct seq_operations::show() being called once
+         * per internal buffer allocation. See single_open(), traverse().
+         */
+        BUG_ON(m->size < PAGE_SIZE);
+        m->count += get_cmdline(task, m->buf, PAGE_SIZE);
+        return 0;
 }
 
-static int proc_pid_auxv(struct task_struct *task, char *buffer)
+static int proc_pid_auxv(struct seq_file *m, struct pid_namespace *ns,
+                         struct pid *pid, struct task_struct *task)
 {
         struct mm_struct *mm = mm_access(task, PTRACE_MODE_READ);
-        int res = PTR_ERR(mm);
         if (mm && !IS_ERR(mm)) {
                 unsigned int nwords = 0;
                 do {
                         nwords += 2;
                 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
-                res = nwords * sizeof(mm->saved_auxv[0]);
-                if (res > PAGE_SIZE)
-                        res = PAGE_SIZE;
-                memcpy(buffer, mm->saved_auxv, res);
+                seq_write(m, mm->saved_auxv, nwords * sizeof(mm->saved_auxv[0]));
                 mmput(mm);
-        }
-        return res;
+                return 0;
+        } else
+                return PTR_ERR(mm);
 }
 
 
@@ -229,7 +230,8 @@ static int proc_pid_auxv(struct task_struct *task, char *buffer)
  * Provides a wchan file via kallsyms in a proper one-value-per-file format.
  * Returns the resolved symbol.  If that fails, simply return the address.
  */
-static int proc_pid_wchan(struct task_struct *task, char *buffer)
+static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns,
+                          struct pid *pid, struct task_struct *task)
 {
         unsigned long wchan;
         char symname[KSYM_NAME_LEN];
@@ -240,9 +242,9 @@ static int proc_pid_wchan(struct task_struct *task, char *buffer)
                 if (!ptrace_may_access(task, PTRACE_MODE_READ))
                         return 0;
                 else
-                        return sprintf(buffer, "%lu", wchan);
+                        return seq_printf(m, "%lu", wchan);
         else
-                return sprintf(buffer, "%s", symname);
+                return seq_printf(m, "%s", symname);
 }
 #endif /* CONFIG_KALLSYMS */
 
@@ -304,9 +306,10 @@ static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns,
 /*
  * Provides /proc/PID/schedstat
  */
-static int proc_pid_schedstat(struct task_struct *task, char *buffer)
+static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns,
+                              struct pid *pid, struct task_struct *task)
 {
-        return sprintf(buffer, "%llu %llu %lu\n",
+        return seq_printf(m, "%llu %llu %lu\n",
                         (unsigned long long)task->se.sum_exec_runtime,
                         (unsigned long long)task->sched_info.run_delay,
                         task->sched_info.pcount);
@@ -404,7 +407,8 @@ static const struct file_operations proc_cpuset_operations = {
 };
 #endif
 
-static int proc_oom_score(struct task_struct *task, char *buffer)
+static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns,
+                          struct pid *pid, struct task_struct *task)
 {
         unsigned long totalpages = totalram_pages + total_swap_pages;
         unsigned long points = 0;
@@ -414,12 +418,12 @@ static int proc_oom_score(struct task_struct *task, char *buffer)
                 points = oom_badness(task, NULL, NULL, totalpages) *
                                                 1000 / totalpages;
         read_unlock(&tasklist_lock);
-        return sprintf(buffer, "%lu\n", points);
+        return seq_printf(m, "%lu\n", points);
 }
 
 struct limit_names {
-        char *name;
-        char *unit;
+        const char *name;
+        const char *unit;
 };
 
 static const struct limit_names lnames[RLIM_NLIMITS] = {
@@ -442,12 +446,11 @@ static const struct limit_names lnames[RLIM_NLIMITS] = {
 };
 
 /* Display limits for a process */
-static int proc_pid_limits(struct task_struct *task, char *buffer)
+static int proc_pid_limits(struct seq_file *m, struct pid_namespace *ns,
+                           struct pid *pid, struct task_struct *task)
 {
         unsigned int i;
-        int count = 0;
         unsigned long flags;
-        char *bufptr = buffer;
 
         struct rlimit rlim[RLIM_NLIMITS];
 
@@ -459,35 +462,34 @@ static int proc_pid_limits(struct task_struct *task, char *buffer)
         /*
          * print the file header
          */
-        count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n",
+       seq_printf(m, "%-25s %-20s %-20s %-10s\n",
                         "Limit", "Soft Limit", "Hard Limit", "Units");
 
         for (i = 0; i < RLIM_NLIMITS; i++) {
                 if (rlim[i].rlim_cur == RLIM_INFINITY)
-                        count += sprintf(&bufptr[count], "%-25s %-20s ",
+                        seq_printf(m, "%-25s %-20s ",
                                          lnames[i].name, "unlimited");
                 else
-                        count += sprintf(&bufptr[count], "%-25s %-20lu ",
+                        seq_printf(m, "%-25s %-20lu ",
                                          lnames[i].name, rlim[i].rlim_cur);
 
                 if (rlim[i].rlim_max == RLIM_INFINITY)
-                        count += sprintf(&bufptr[count], "%-20s ", "unlimited");
+                        seq_printf(m, "%-20s ", "unlimited");
                 else
-                        count += sprintf(&bufptr[count], "%-20lu ",
-                                         rlim[i].rlim_max);
+                        seq_printf(m, "%-20lu ", rlim[i].rlim_max);
 
                 if (lnames[i].unit)
-                        count += sprintf(&bufptr[count], "%-10s\n",
-                                         lnames[i].unit);
+                        seq_printf(m, "%-10s\n", lnames[i].unit);
                 else
-                        count += sprintf(&bufptr[count], "\n");
+                        seq_putc(m, '\n');
         }
 
-        return count;
+        return 0;
 }
 
 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
-static int proc_pid_syscall(struct task_struct *task, char *buffer)
+static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns,
+                            struct pid *pid, struct task_struct *task)
 {
         long nr;
         unsigned long args[6], sp, pc;
@@ -496,11 +498,11 @@ static int proc_pid_syscall(struct task_struct *task, char *buffer)
                 return res;
 
         if (task_current_syscall(task, &nr, args, 6, &sp, &pc))
-                res = sprintf(buffer, "running\n");
+                seq_puts(m, "running\n");
         else if (nr < 0)
-                res = sprintf(buffer, "%ld 0x%lx 0x%lx\n", nr, sp, pc);
+                seq_printf(m, "%ld 0x%lx 0x%lx\n", nr, sp, pc);
         else
-                res = sprintf(buffer,
+                seq_printf(m,
                        "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
                        nr,
                        args[0], args[1], args[2], args[3], args[4], args[5],
@@ -598,43 +600,6 @@ static const struct inode_operations proc_def_inode_operations = {
         .setattr        = proc_setattr,
 };
 
-#define PROC_BLOCK_SIZE (3*1024)                /* 4K page size but our output routines use some slack for overruns */
-
-static ssize_t proc_info_read(struct file * file, char __user * buf,
-                          size_t count, loff_t *ppos)
-{
-        struct inode * inode = file_inode(file);
-        unsigned long page;
-        ssize_t length;
-        struct task_struct *task = get_proc_task(inode);
-
-        length = -ESRCH;
-        if (!task)
-                goto out_no_task;
-
-        if (count > PROC_BLOCK_SIZE)
-                count = PROC_BLOCK_SIZE;
-
-        length = -ENOMEM;
-        if (!(page = __get_free_page(GFP_TEMPORARY)))
-                goto out;
-
-        length = PROC_I(inode)->op.proc_read(task, (char*)page);
-
-        if (length >= 0)
-                length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
-        free_page(page);
-out:
-        put_task_struct(task);
-out_no_task:
-        return length;
-}
-
-static const struct file_operations proc_info_file_operations = {
-        .read           = proc_info_read,
-        .llseek         = generic_file_llseek,
-};
-
 static int proc_single_show(struct seq_file *m, void *v)
 {
         struct inode *inode = m->private;
@@ -2056,7 +2021,7 @@ static int show_timer(struct seq_file *m, void *v)
         struct k_itimer *timer;
         struct timers_private *tp = m->private;
         int notify;
-        static char *nstr[] = {
+        static const char * const nstr[] = {
                 [SIGEV_SIGNAL] = "signal",
                 [SIGEV_NONE] = "none",
                 [SIGEV_THREAD] = "thread",
@@ -2392,7 +2357,7 @@ static const struct file_operations proc_coredump_filter_operations = {
 #endif
 
 #ifdef CONFIG_TASK_IO_ACCOUNTING
-static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
+static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole)
 {
         struct task_io_accounting acct = task->ioac;
         unsigned long flags;
@@ -2416,7 +2381,7 @@ static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
 
                 unlock_task_sighand(task, &flags);
         }
-        result = sprintf(buffer,
+        result = seq_printf(m,
                         "rchar: %llu\n"
                         "wchar: %llu\n"
                         "syscr: %llu\n"
@@ -2436,20 +2401,22 @@ out_unlock:
         return result;
 }
 
-static int proc_tid_io_accounting(struct task_struct *task, char *buffer)
+static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
+                                  struct pid *pid, struct task_struct *task)
 {
-        return do_io_accounting(task, buffer, 0);
+        return do_io_accounting(task, m, 0);
 }
 
-static int proc_tgid_io_accounting(struct task_struct *task, char *buffer)
+static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
+                                   struct pid *pid, struct task_struct *task)
 {
-        return do_io_accounting(task, buffer, 1);
+        return do_io_accounting(task, m, 1);
 }
 #endif /* CONFIG_TASK_IO_ACCOUNTING */
 
 #ifdef CONFIG_USER_NS
 static int proc_id_map_open(struct inode *inode, struct file *file,
-        struct seq_operations *seq_ops)
+        const struct seq_operations *seq_ops)
 {
         struct user_namespace *ns = NULL;
         struct task_struct *task;
@@ -2557,10 +2524,10 @@ static const struct pid_entry tgid_base_stuff[] = {
         DIR("net",        S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
 #endif
         REG("environ",    S_IRUSR, proc_environ_operations),
-        INF("auxv",       S_IRUSR, proc_pid_auxv),
+        ONE("auxv",       S_IRUSR, proc_pid_auxv),
         ONE("status",     S_IRUGO, proc_pid_status),
         ONE("personality", S_IRUSR, proc_pid_personality),
-        INF("limits",     S_IRUGO, proc_pid_limits),
+        ONE("limits",     S_IRUGO, proc_pid_limits),
 #ifdef CONFIG_SCHED_DEBUG
         REG("sched",      S_IRUGO|S_IWUSR, proc_pid_sched_operations),
 #endif
@@ -2569,9 +2536,9 @@ static const struct pid_entry tgid_base_stuff[] = {
 #endif
         REG("comm",      S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
-        INF("syscall",    S_IRUSR, proc_pid_syscall),
+        ONE("syscall",    S_IRUSR, proc_pid_syscall),
 #endif
-        INF("cmdline",    S_IRUGO, proc_pid_cmdline),
+        ONE("cmdline",    S_IRUGO, proc_pid_cmdline),
         ONE("stat",       S_IRUGO, proc_tgid_stat),
         ONE("statm",      S_IRUGO, proc_pid_statm),
         REG("maps",       S_IRUGO, proc_pid_maps_operations),
@@ -2594,13 +2561,13 @@ static const struct pid_entry tgid_base_stuff[] = {
         DIR("attr",       S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
 #endif
 #ifdef CONFIG_KALLSYMS
-        INF("wchan",      S_IRUGO, proc_pid_wchan),
+        ONE("wchan",      S_IRUGO, proc_pid_wchan),
 #endif
 #ifdef CONFIG_STACKTRACE
         ONE("stack",      S_IRUSR, proc_pid_stack),
 #endif
 #ifdef CONFIG_SCHEDSTATS
-        INF("schedstat",  S_IRUGO, proc_pid_schedstat),
+        ONE("schedstat",  S_IRUGO, proc_pid_schedstat),
 #endif
 #ifdef CONFIG_LATENCYTOP
         REG("latency",  S_IRUGO, proc_lstats_operations),
@@ -2611,7 +2578,7 @@ static const struct pid_entry tgid_base_stuff[] = {
 #ifdef CONFIG_CGROUPS
         REG("cgroup",  S_IRUGO, proc_cgroup_operations),
 #endif
-        INF("oom_score",  S_IRUGO, proc_oom_score),
+        ONE("oom_score",  S_IRUGO, proc_oom_score),
         REG("oom_adj",    S_IRUGO|S_IWUSR, proc_oom_adj_operations),
         REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
 #ifdef CONFIG_AUDITSYSCALL
@@ -2625,10 +2592,10 @@ static const struct pid_entry tgid_base_stuff[] = {
         REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
 #endif
 #ifdef CONFIG_TASK_IO_ACCOUNTING
-        INF("io",       S_IRUSR, proc_tgid_io_accounting),
+        ONE("io",       S_IRUSR, proc_tgid_io_accounting),
 #endif
 #ifdef CONFIG_HARDWALL
-        INF("hardwall",   S_IRUGO, proc_pid_hardwall),
+        ONE("hardwall",   S_IRUGO, proc_pid_hardwall),
 #endif
 #ifdef CONFIG_USER_NS
         REG("uid_map",    S_IRUGO|S_IWUSR, proc_uid_map_operations),
@@ -2780,12 +2747,12 @@ out:
 
 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
 {
-        int result = 0;
+        int result = -ENOENT;
         struct task_struct *task;
         unsigned tgid;
         struct pid_namespace *ns;
 
-        tgid = name_to_int(dentry);
+        tgid = name_to_int(&dentry->d_name);
         if (tgid == ~0U)
                 goto out;
 
@@ -2896,18 +2863,18 @@ static const struct pid_entry tid_base_stuff[] = {
         DIR("fdinfo",    S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
         DIR("ns",        S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
         REG("environ",   S_IRUSR, proc_environ_operations),
-        INF("auxv",      S_IRUSR, proc_pid_auxv),
+        ONE("auxv",      S_IRUSR, proc_pid_auxv),
         ONE("status",    S_IRUGO, proc_pid_status),
         ONE("personality", S_IRUSR, proc_pid_personality),
-        INF("limits",    S_IRUGO, proc_pid_limits),
+        ONE("limits",    S_IRUGO, proc_pid_limits),
 #ifdef CONFIG_SCHED_DEBUG
         REG("sched",     S_IRUGO|S_IWUSR, proc_pid_sched_operations),
 #endif
         REG("comm",      S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
-        INF("syscall",   S_IRUSR, proc_pid_syscall),
+        ONE("syscall",   S_IRUSR, proc_pid_syscall),
 #endif
-        INF("cmdline",   S_IRUGO, proc_pid_cmdline),
+        ONE("cmdline",   S_IRUGO, proc_pid_cmdline),
         ONE("stat",      S_IRUGO, proc_tid_stat),
         ONE("statm",     S_IRUGO, proc_pid_statm),
         REG("maps",      S_IRUGO, proc_tid_maps_operations),
@@ -2932,13 +2899,13 @@ static const struct pid_entry tid_base_stuff[] = {
         DIR("attr",      S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
 #endif
 #ifdef CONFIG_KALLSYMS
-        INF("wchan",     S_IRUGO, proc_pid_wchan),
+        ONE("wchan",     S_IRUGO, proc_pid_wchan),
 #endif
 #ifdef CONFIG_STACKTRACE
         ONE("stack",      S_IRUSR, proc_pid_stack),
 #endif
 #ifdef CONFIG_SCHEDSTATS
-        INF("schedstat", S_IRUGO, proc_pid_schedstat),
+        ONE("schedstat", S_IRUGO, proc_pid_schedstat),
 #endif
 #ifdef CONFIG_LATENCYTOP
         REG("latency",  S_IRUGO, proc_lstats_operations),
@@ -2949,7 +2916,7 @@ static const struct pid_entry tid_base_stuff[] = {
 #ifdef CONFIG_CGROUPS
         REG("cgroup",  S_IRUGO, proc_cgroup_operations),
 #endif
-        INF("oom_score", S_IRUGO, proc_oom_score),
+        ONE("oom_score", S_IRUGO, proc_oom_score),
         REG("oom_adj",   S_IRUGO|S_IWUSR, proc_oom_adj_operations),
         REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
 #ifdef CONFIG_AUDITSYSCALL
@@ -2960,10 +2927,10 @@ static const struct pid_entry tid_base_stuff[] = {
         REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
 #endif
 #ifdef CONFIG_TASK_IO_ACCOUNTING
-        INF("io",       S_IRUSR, proc_tid_io_accounting),
+        ONE("io",       S_IRUSR, proc_tid_io_accounting),
 #endif
 #ifdef CONFIG_HARDWALL
-        INF("hardwall",   S_IRUGO, proc_pid_hardwall),
+        ONE("hardwall",   S_IRUGO, proc_pid_hardwall),
 #endif
 #ifdef CONFIG_USER_NS
         REG("uid_map",    S_IRUGO|S_IWUSR, proc_uid_map_operations),
@@ -3033,7 +3000,7 @@ static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry
         if (!leader)
                 goto out_no_task;
 
-        tid = name_to_int(dentry);
+        tid = name_to_int(&dentry->d_name);
         if (tid == ~0U)
                 goto out;