[PATCH 5/7] fs: Convert show_fdinfo functions to void

From: Joe Perches
Date: Mon Sep 29 2014 - 19:10:29 EST

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

Update vfs documentation.

Signed-off-by: Joe Perches <joe@xxxxxxxxxxx>
---
Documentation/filesystems/vfs.txt | 2 +-
drivers/net/tun.c | 4 +--
fs/eventfd.c | 15 +++-----
fs/eventpoll.c | 19 ++++------
fs/notify/fdinfo.c | 76 +++++++++++++++++----------------------
fs/notify/fdinfo.h | 4 +--
fs/proc/fd.c | 2 +-
fs/signalfd.c | 10 ++----
fs/timerfd.c | 27 +++++++-------
include/linux/fs.h | 2 +-
10 files changed, 68 insertions(+), 93 deletions(-)

diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index fceff7c..af1dbc1 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -828,7 +828,7 @@ struct file_operations {
ssize_t (*splice_read)(struct file *, struct pipe_inode_info *, size_t, unsigned int);
int (*setlease)(struct file *, long arg, struct file_lock **, void **);
long (*fallocate)(struct file *, int mode, loff_t offset, loff_t len);
- int (*show_fdinfo)(struct seq_file *m, struct file *f);
+ void (*show_fdinfo)(struct seq_file *m, struct file *f);
};

Again, all methods are called without any locks being held, unless
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 186ce54..a3420e0 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -2209,7 +2209,7 @@ static int tun_chr_close(struct inode *inode, struct file *file)
}

#ifdef CONFIG_PROC_FS
-static int tun_chr_show_fdinfo(struct seq_file *m, struct file *f)
+static void tun_chr_show_fdinfo(struct seq_file *m, struct file *f)
{
struct tun_struct *tun;
struct ifreq ifr;
@@ -2225,7 +2225,7 @@ static int tun_chr_show_fdinfo(struct seq_file *m, struct file *f)
if (tun)
tun_put(tun);

- return seq_printf(m, "iff:\t%s\n", ifr.ifr_name);
+ seq_printf(m, "iff:\t%s\n", ifr.ifr_name);
}
#endif

diff --git a/fs/eventfd.c b/fs/eventfd.c
index d6a88e7..abcb25d 100644
--- a/fs/eventfd.c
+++ b/fs/eventfd.c
@@ -286,25 +286,20 @@ static ssize_t eventfd_write(struct file *file, const char __user *buf, size_t c
return res;
}

-#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)
{
+#ifdef CONFIG_PROC_FS
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
+}

static const struct file_operations eventfd_fops = {
-#ifdef CONFIG_PROC_FS
.show_fdinfo = eventfd_show_fdinfo,
-#endif
.release = eventfd_release,
.poll = eventfd_poll,
.read = eventfd_read,
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 7bcfff9..4e742b6 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -869,34 +869,29 @@ static unsigned int ep_eventpoll_poll(struct file *file, poll_table *wait)
return pollflags != -1 ? pollflags : 0;
}

-#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)
{
+#ifdef CONFIG_PROC_FS
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_is_full(m))
break;
}
mutex_unlock(&ep->mtx);
-
- return ret;
-}
#endif
+}

/* File callbacks that implement the eventpoll file behaviour */
static const struct file_operations eventpoll_fops = {
-#ifdef CONFIG_PROC_FS
.show_fdinfo = ep_show_fdinfo,
-#endif
.release = ep_eventpoll_release,
.poll = ep_eventpoll_poll,
.llseek = noop_llseek,
diff --git a/fs/notify/fdinfo.c b/fs/notify/fdinfo.c
index 9d7e2b9..0bb10b7 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_is_full(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;
@@ -125,25 +115,23 @@ static int fanotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
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');
+ 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 +157,7 @@ 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 556afda..9664c49 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 e11d7c5..4c3c253 100644
--- a/fs/proc/fd.c
+++ b/fs/proc/fd.c
@@ -53,7 +53,7 @@ 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);
fput(file);
}

diff --git a/fs/signalfd.c b/fs/signalfd.c
index 424b7b6..06bd5a2 100644
--- a/fs/signalfd.c
+++ b/fs/signalfd.c
@@ -229,24 +229,20 @@ static ssize_t signalfd_read(struct file *file, char __user *buf, size_t count,
return total ? total: ret;
}

-#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)
{
+#ifdef CONFIG_PROC_FS
struct signalfd_ctx *ctx = f->private_data;
sigset_t sigmask;

sigmask = ctx->sigmask;
signotset(&sigmask);
render_sigset_t(m, "sigmask:\t", &sigmask);
-
- return 0;
-}
#endif
+}

static const struct file_operations signalfd_fops = {
-#ifdef CONFIG_PROC_FS
.show_fdinfo = signalfd_show_fdinfo,
-#endif
.release = signalfd_release,
.poll = signalfd_poll,
.read = signalfd_read,
diff --git a/fs/timerfd.c b/fs/timerfd.c
index b46ffa9..b94fa6c 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
diff --git a/include/linux/fs.h b/include/linux/fs.h
index a4ce5bae..e2f67f0 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1494,7 +1494,7 @@ struct file_operations {
int (*setlease)(struct file *, long, struct file_lock **, void **);
long (*fallocate)(struct file *file, int mode, loff_t offset,
loff_t len);
- int (*show_fdinfo)(struct seq_file *m, struct file *f);
+ void (*show_fdinfo)(struct seq_file *m, struct file *f);
};

struct inode_operations {
--
1.8.1.2.459.gbcd45b4.dirty

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