fs, epoll: add procfs fdinfo helper
This allows us to print out eventpoll target file descriptor, events and
data, the /proc/pid/fdinfo/fd consists of
| pos: 0
| flags: 02
| tfd: 5 events: 1d data: ffffffffffffffff enabled: 1
[avagin@: fix for unitialized ret variable]
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrey Vagin <avagin@openvz.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: James Bottomley <jbottomley@parallels.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Matthew Helsley <matt.helsley@gmail.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@onelan.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index cd96649..be56b21 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -38,6 +38,8 @@
#include <asm/io.h>
#include <asm/mman.h>
#include <linux/atomic.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
/*
* LOCKING:
@@ -783,8 +785,34 @@
return pollflags != -1 ? pollflags : 0;
}
+#ifdef CONFIG_PROC_FS
+static int 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)
+ 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/proc/array.c b/fs/proc/array.c
index 439544f..060a56a 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -220,7 +220,7 @@
seq_putc(m, '\n');
}
-static void render_sigset_t(struct seq_file *m, const char *header,
+void render_sigset_t(struct seq_file *m, const char *header,
sigset_t *set)
{
int i;
diff --git a/fs/signalfd.c b/fs/signalfd.c
index 8bee4e5..b534869 100644
--- a/fs/signalfd.c
+++ b/fs/signalfd.c
@@ -29,6 +29,7 @@
#include <linux/anon_inodes.h>
#include <linux/signalfd.h>
#include <linux/syscalls.h>
+#include <linux/proc_fs.h>
void signalfd_cleanup(struct sighand_struct *sighand)
{
@@ -227,7 +228,24 @@
return total ? total: ret;
}
+#ifdef CONFIG_PROC_FS
+static int signalfd_show_fdinfo(struct seq_file *m, struct file *f)
+{
+ 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/include/linux/proc_fs.h b/include/linux/proc_fs.h
index 3fd2e87..b4f70f0 100644
--- a/include/linux/proc_fs.h
+++ b/include/linux/proc_fs.h
@@ -290,4 +290,7 @@
return pde->parent->data;
}
+#include <linux/signal.h>
+
+void render_sigset_t(struct seq_file *m, const char *header, sigset_t *set);
#endif /* _LINUX_PROC_FS_H */