fs: Convert show_fdinfo functions to void

seq_printf functions shouldn't really check the return value.
Checking seq_has_overflowed() occasionally is used instead.

Update vfs documentation.

Link: http://lkml.kernel.org/p/e37e6e7b76acbdcc3bb4ab2a57c8f8ca1ae11b9a.1412031505.git.joe@perches.com

Cc: David S. Miller <davem@davemloft.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Joe Perches <joe@perches.com>
[ did a few clean ups ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

7 files changed, 59 insertions, 79 deletions

diff --git a/fs/eventfd.c b/fs/eventfd.c
index d6a88e7812f3..4b0a226024fa 100644
--- a/fs/eventfd.c
+++ b/fs/eventfd.c
@@ -287,17 +287,14 @@ static ssize_t eventfd_write(struct file *file, const char __user *buf, size_t c
 }
 
 #ifdef CONFIG_PROC_FS
-static int eventfd_show_fdinfo(struct seq_file *m, struct file *f)
+static void eventfd_show_fdinfo(struct seq_file *m, struct file *f)
 {
         struct eventfd_ctx *ctx = f->private_data;
-        int ret;
 
         spin_lock_irq(&ctx->wqh.lock);
-        ret = seq_printf(m, "eventfd-count: %16llx\n",
-                         (unsigned long long)ctx->count);
+        seq_printf(m, "eventfd-count: %16llx\n",
+                   (unsigned long long)ctx->count);
         spin_unlock_irq(&ctx->wqh.lock);
-
-        return ret;
 }
 #endif
 
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 7bcfff900f05..d77f94491352 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -870,25 +870,22 @@ static unsigned int ep_eventpoll_poll(struct file *file, poll_table *wait)
 }
 
 #ifdef CONFIG_PROC_FS
-static int ep_show_fdinfo(struct seq_file *m, struct file *f)
+static void ep_show_fdinfo(struct seq_file *m, struct file *f)
 {
         struct eventpoll *ep = f->private_data;
         struct rb_node *rbp;
-        int ret = 0;
 
         mutex_lock(&ep->mtx);
         for (rbp = rb_first(&ep->rbr); rbp; rbp = rb_next(rbp)) {
                 struct epitem *epi = rb_entry(rbp, struct epitem, rbn);
 
-                ret = seq_printf(m, "tfd: %8d events: %8x data: %16llx\n",
-                                 epi->ffd.fd, epi->event.events,
-                                 (long long)epi->event.data);
-                if (ret)
+                seq_printf(m, "tfd: %8d events: %8x data: %16llx\n",
+                           epi->ffd.fd, epi->event.events,
+                           (long long)epi->event.data);
+                if (seq_has_overflowed(m))
                         break;
         }
         mutex_unlock(&ep->mtx);
-
-        return ret;
 }
 #endif
 
diff --git a/fs/notify/fdinfo.c b/fs/notify/fdinfo.c
index 9d7e2b9659cb..6ffd220eb14d 100644
--- a/fs/notify/fdinfo.c
+++ b/fs/notify/fdinfo.c
@@ -20,25 +20,24 @@
 
 #if defined(CONFIG_INOTIFY_USER) || defined(CONFIG_FANOTIFY)
 
-static int show_fdinfo(struct seq_file *m, struct file *f,
-                       int (*show)(struct seq_file *m, struct fsnotify_mark *mark))
+static void show_fdinfo(struct seq_file *m, struct file *f,
+                        void (*show)(struct seq_file *m,
+                                     struct fsnotify_mark *mark))
 {
         struct fsnotify_group *group = f->private_data;
         struct fsnotify_mark *mark;
-        int ret = 0;
 
         mutex_lock(&group->mark_mutex);
         list_for_each_entry(mark, &group->marks_list, g_list) {
-                ret = show(m, mark);
-                if (ret)
+                show(m, mark);
+                if (seq_has_overflowed(m))
                         break;
         }
         mutex_unlock(&group->mark_mutex);
-        return ret;
 }
 
 #if defined(CONFIG_EXPORTFS)
-static int show_mark_fhandle(struct seq_file *m, struct inode *inode)
+static void show_mark_fhandle(struct seq_file *m, struct inode *inode)
 {
         struct {
                 struct file_handle handle;
@@ -52,71 +51,62 @@ static int show_mark_fhandle(struct seq_file *m, struct inode *inode)
         ret = exportfs_encode_inode_fh(inode, (struct fid *)f.handle.f_handle, &size, 0);
         if ((ret == FILEID_INVALID) || (ret < 0)) {
                 WARN_ONCE(1, "Can't encode file handler for inotify: %d\n", ret);
-                return 0;
+                return;
         }
 
         f.handle.handle_type = ret;
         f.handle.handle_bytes = size * sizeof(u32);
 
-        ret = seq_printf(m, "fhandle-bytes:%x fhandle-type:%x f_handle:",
-                         f.handle.handle_bytes, f.handle.handle_type);
+        seq_printf(m, "fhandle-bytes:%x fhandle-type:%x f_handle:",
+                   f.handle.handle_bytes, f.handle.handle_type);
 
         for (i = 0; i < f.handle.handle_bytes; i++)
-                ret |= seq_printf(m, "%02x", (int)f.handle.f_handle[i]);
-
-        return ret;
+                seq_printf(m, "%02x", (int)f.handle.f_handle[i]);
 }
 #else
-static int show_mark_fhandle(struct seq_file *m, struct inode *inode)
+static void show_mark_fhandle(struct seq_file *m, struct inode *inode)
 {
-        return 0;
 }
 #endif
 
 #ifdef CONFIG_INOTIFY_USER
 
-static int inotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
+static void inotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
 {
         struct inotify_inode_mark *inode_mark;
         struct inode *inode;
-        int ret = 0;
 
         if (!(mark->flags & (FSNOTIFY_MARK_FLAG_ALIVE | FSNOTIFY_MARK_FLAG_INODE)))
-                return 0;
+                return;
 
         inode_mark = container_of(mark, struct inotify_inode_mark, fsn_mark);
         inode = igrab(mark->i.inode);
         if (inode) {
-                ret = seq_printf(m, "inotify wd:%x ino:%lx sdev:%x "
-                                 "mask:%x ignored_mask:%x ",
-                                 inode_mark->wd, inode->i_ino,
-                                 inode->i_sb->s_dev,
-                                 mark->mask, mark->ignored_mask);
-                ret |= show_mark_fhandle(m, inode);
-                ret |= seq_putc(m, '\n');
+                seq_printf(m, "inotify wd:%x ino:%lx sdev:%x mask:%x ignored_mask:%x ",
+                           inode_mark->wd, inode->i_ino, inode->i_sb->s_dev,
+                           mark->mask, mark->ignored_mask);
+                show_mark_fhandle(m, inode);
+                seq_putc(m, '\n');
                 iput(inode);
         }
-
-        return ret;
 }
 
-int inotify_show_fdinfo(struct seq_file *m, struct file *f)
+void inotify_show_fdinfo(struct seq_file *m, struct file *f)
 {
-        return show_fdinfo(m, f, inotify_fdinfo);
+        show_fdinfo(m, f, inotify_fdinfo);
 }
 
 #endif /* CONFIG_INOTIFY_USER */
 
 #ifdef CONFIG_FANOTIFY
 
-static int fanotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
+static void fanotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
 {
         unsigned int mflags = 0;
         struct inode *inode;
-        int ret = 0;
 
         if (!(mark->flags & FSNOTIFY_MARK_FLAG_ALIVE))
-                return 0;
+                return;
 
         if (mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY)
                 mflags |= FAN_MARK_IGNORED_SURV_MODIFY;
@@ -124,26 +114,22 @@ static int fanotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
         if (mark->flags & FSNOTIFY_MARK_FLAG_INODE) {
                 inode = igrab(mark->i.inode);
                 if (!inode)
-                        goto out;
-                ret = seq_printf(m, "fanotify ino:%lx sdev:%x "
-                                 "mflags:%x mask:%x ignored_mask:%x ",
-                                 inode->i_ino, inode->i_sb->s_dev,
-                                 mflags, mark->mask, mark->ignored_mask);
-                ret |= show_mark_fhandle(m, inode);
-                ret |= seq_putc(m, '\n');
+                        return;
+                seq_printf(m, "fanotify ino:%lx sdev:%x mflags:%x mask:%x ignored_mask:%x ",
+                           inode->i_ino, inode->i_sb->s_dev,
+                           mflags, mark->mask, mark->ignored_mask);
+                show_mark_fhandle(m, inode);
+                seq_putc(m, '\n');
                 iput(inode);
         } else if (mark->flags & FSNOTIFY_MARK_FLAG_VFSMOUNT) {
                 struct mount *mnt = real_mount(mark->m.mnt);
 
-                ret = seq_printf(m, "fanotify mnt_id:%x mflags:%x mask:%x "
-                                 "ignored_mask:%x\n", mnt->mnt_id, mflags,
-                                 mark->mask, mark->ignored_mask);
+                seq_printf(m, "fanotify mnt_id:%x mflags:%x mask:%x ignored_mask:%x\n",
+                           mnt->mnt_id, mflags, mark->mask, mark->ignored_mask);
         }
-out:
-        return ret;
 }
 
-int fanotify_show_fdinfo(struct seq_file *m, struct file *f)
+void fanotify_show_fdinfo(struct seq_file *m, struct file *f)
 {
         struct fsnotify_group *group = f->private_data;
         unsigned int flags = 0;
@@ -169,7 +155,7 @@ int fanotify_show_fdinfo(struct seq_file *m, struct file *f)
         seq_printf(m, "fanotify flags:%x event-flags:%x\n",
                    flags, group->fanotify_data.f_flags);
 
-        return show_fdinfo(m, f, fanotify_fdinfo);
+        show_fdinfo(m, f, fanotify_fdinfo);
 }
 
 #endif /* CONFIG_FANOTIFY */
diff --git a/fs/notify/fdinfo.h b/fs/notify/fdinfo.h
index 556afda990e9..9664c4904d6b 100644
--- a/fs/notify/fdinfo.h
+++ b/fs/notify/fdinfo.h
@@ -10,11 +10,11 @@ struct file;
 #ifdef CONFIG_PROC_FS
 
 #ifdef CONFIG_INOTIFY_USER
-extern int inotify_show_fdinfo(struct seq_file *m, struct file *f);
+void inotify_show_fdinfo(struct seq_file *m, struct file *f);
 #endif
 
 #ifdef CONFIG_FANOTIFY
-extern int fanotify_show_fdinfo(struct seq_file *m, struct file *f);
+void fanotify_show_fdinfo(struct seq_file *m, struct file *f);
 #endif
 
 #else /* CONFIG_PROC_FS */
diff --git a/fs/proc/fd.c b/fs/proc/fd.c
index e11d7c590bb0..8e5ad83b629a 100644
--- a/fs/proc/fd.c
+++ b/fs/proc/fd.c
@@ -53,7 +53,8 @@ static int seq_show(struct seq_file *m, void *v)
                            (long long)file->f_pos, f_flags,
                            real_mount(file->f_path.mnt)->mnt_id);
                 if (file->f_op->show_fdinfo)
-                        ret = file->f_op->show_fdinfo(m, file);
+                        file->f_op->show_fdinfo(m, file);
+                ret = seq_has_overflowed(m);
                 fput(file);
         }
 
diff --git a/fs/signalfd.c b/fs/signalfd.c
index 424b7b65321f..7e412ad74836 100644
--- a/fs/signalfd.c
+++ b/fs/signalfd.c
@@ -230,7 +230,7 @@ static ssize_t signalfd_read(struct file *file, char __user *buf, size_t count,
 }
 
 #ifdef CONFIG_PROC_FS
-static int signalfd_show_fdinfo(struct seq_file *m, struct file *f)
+static void signalfd_show_fdinfo(struct seq_file *m, struct file *f)
 {
         struct signalfd_ctx *ctx = f->private_data;
         sigset_t sigmask;
@@ -238,8 +238,6 @@ static int signalfd_show_fdinfo(struct seq_file *m, struct file *f)
         sigmask = ctx->sigmask;
         signotset(&sigmask);
         render_sigset_t(m, "sigmask:\t", &sigmask);
-
-        return 0;
 }
 #endif
 
diff --git a/fs/timerfd.c b/fs/timerfd.c
index b46ffa94372a..b94fa6c3c6eb 100644
--- a/fs/timerfd.c
+++ b/fs/timerfd.c
@@ -288,7 +288,7 @@ static ssize_t timerfd_read(struct file *file, char __user *buf, size_t count,
 }
 
 #ifdef CONFIG_PROC_FS
-static int timerfd_show(struct seq_file *m, struct file *file)
+static void timerfd_show(struct seq_file *m, struct file *file)
 {
         struct timerfd_ctx *ctx = file->private_data;
         struct itimerspec t;
@@ -298,18 +298,19 @@ static int timerfd_show(struct seq_file *m, struct file *file)
         t.it_interval = ktime_to_timespec(ctx->tintv);
         spin_unlock_irq(&ctx->wqh.lock);
 
-        return seq_printf(m,
-                          "clockid: %d\n"
-                          "ticks: %llu\n"
-                          "settime flags: 0%o\n"
-                          "it_value: (%llu, %llu)\n"
-                          "it_interval: (%llu, %llu)\n",
-                          ctx->clockid, (unsigned long long)ctx->ticks,
-                          ctx->settime_flags,
-                          (unsigned long long)t.it_value.tv_sec,
-                          (unsigned long long)t.it_value.tv_nsec,
-                          (unsigned long long)t.it_interval.tv_sec,
-                          (unsigned long long)t.it_interval.tv_nsec);
+        seq_printf(m,
+                   "clockid: %d\n"
+                   "ticks: %llu\n"
+                   "settime flags: 0%o\n"
+                   "it_value: (%llu, %llu)\n"
+                   "it_interval: (%llu, %llu)\n",
+                   ctx->clockid,
+                   (unsigned long long)ctx->ticks,
+                   ctx->settime_flags,
+                   (unsigned long long)t.it_value.tv_sec,
+                   (unsigned long long)t.it_value.tv_nsec,
+                   (unsigned long long)t.it_interval.tv_sec,
+                   (unsigned long long)t.it_interval.tv_nsec);
 }
 #else
 #define timerfd_show NULL