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-rw-r--r--fs/relayfs/relay.c77
1 files changed, 64 insertions, 13 deletions
diff --git a/fs/relayfs/relay.c b/fs/relayfs/relay.c
index 16446a1..abf3cea 100644
--- a/fs/relayfs/relay.c
+++ b/fs/relayfs/relay.c
@@ -80,11 +80,34 @@ static void buf_unmapped_default_callback(struct rchan_buf *buf,
{
}
+/*
+ * create_buf_file_create() default callback. Creates file to represent buf.
+ */
+static struct dentry *create_buf_file_default_callback(const char *filename,
+ struct dentry *parent,
+ int mode,
+ struct rchan_buf *buf,
+ int *is_global)
+{
+ return relayfs_create_file(filename, parent, mode,
+ &relay_file_operations, buf);
+}
+
+/*
+ * remove_buf_file() default callback. Removes file representing relay buffer.
+ */
+static int remove_buf_file_default_callback(struct dentry *dentry)
+{
+ return relayfs_remove(dentry);
+}
+
/* relay channel default callbacks */
static struct rchan_callbacks default_channel_callbacks = {
.subbuf_start = subbuf_start_default_callback,
.buf_mapped = buf_mapped_default_callback,
.buf_unmapped = buf_unmapped_default_callback,
+ .create_buf_file = create_buf_file_default_callback,
+ .remove_buf_file = remove_buf_file_default_callback,
};
/**
@@ -148,14 +171,16 @@ static inline void __relay_reset(struct rchan_buf *buf, unsigned int init)
void relay_reset(struct rchan *chan)
{
unsigned int i;
+ struct rchan_buf *prev = NULL;
if (!chan)
return;
for (i = 0; i < NR_CPUS; i++) {
- if (!chan->buf[i])
- continue;
+ if (!chan->buf[i] || chan->buf[i] == prev)
+ break;
__relay_reset(chan->buf[i], 0);
+ prev = chan->buf[i];
}
}
@@ -166,17 +191,27 @@ void relay_reset(struct rchan *chan)
*/
static struct rchan_buf *relay_open_buf(struct rchan *chan,
const char *filename,
- struct dentry *parent)
+ struct dentry *parent,
+ int *is_global)
{
struct rchan_buf *buf;
struct dentry *dentry;
+ if (*is_global)
+ return chan->buf[0];
+
+ buf = relay_create_buf(chan);
+ if (!buf)
+ return NULL;
+
/* Create file in fs */
- dentry = relayfs_create_file(filename, parent, S_IRUSR, chan);
- if (!dentry)
+ dentry = chan->cb->create_buf_file(filename, parent, S_IRUSR,
+ buf, is_global);
+ if (!dentry) {
+ relay_destroy_buf(buf);
return NULL;
+ }
- buf = RELAYFS_I(dentry->d_inode)->buf;
buf->dentry = dentry;
__relay_reset(buf, 1);
@@ -214,6 +249,10 @@ static inline void setup_callbacks(struct rchan *chan,
cb->buf_mapped = buf_mapped_default_callback;
if (!cb->buf_unmapped)
cb->buf_unmapped = buf_unmapped_default_callback;
+ if (!cb->create_buf_file)
+ cb->create_buf_file = create_buf_file_default_callback;
+ if (!cb->remove_buf_file)
+ cb->remove_buf_file = remove_buf_file_default_callback;
chan->cb = cb;
}
@@ -241,6 +280,7 @@ struct rchan *relay_open(const char *base_filename,
unsigned int i;
struct rchan *chan;
char *tmpname;
+ int is_global = 0;
if (!base_filename)
return NULL;
@@ -265,7 +305,8 @@ struct rchan *relay_open(const char *base_filename,
for_each_online_cpu(i) {
sprintf(tmpname, "%s%d", base_filename, i);
- chan->buf[i] = relay_open_buf(chan, tmpname, parent);
+ chan->buf[i] = relay_open_buf(chan, tmpname, parent,
+ &is_global);
chan->buf[i]->cpu = i;
if (!chan->buf[i])
goto free_bufs;
@@ -279,6 +320,8 @@ free_bufs:
if (!chan->buf[i])
break;
relay_close_buf(chan->buf[i]);
+ if (is_global)
+ break;
}
kfree(tmpname);
@@ -333,8 +376,7 @@ size_t relay_switch_subbuf(struct rchan_buf *buf, size_t length)
return length;
toobig:
- printk(KERN_WARNING "relayfs: event too large (%Zd)\n", length);
- WARN_ON(1);
+ buf->chan->last_toobig = length;
return 0;
}
@@ -389,16 +431,23 @@ void relay_destroy_channel(struct kref *kref)
void relay_close(struct rchan *chan)
{
unsigned int i;
+ struct rchan_buf *prev = NULL;
if (!chan)
return;
for (i = 0; i < NR_CPUS; i++) {
- if (!chan->buf[i])
- continue;
+ if (!chan->buf[i] || chan->buf[i] == prev)
+ break;
relay_close_buf(chan->buf[i]);
+ prev = chan->buf[i];
}
+ if (chan->last_toobig)
+ printk(KERN_WARNING "relayfs: one or more items not logged "
+ "[item size (%Zd) > sub-buffer size (%Zd)]\n",
+ chan->last_toobig, chan->subbuf_size);
+
kref_put(&chan->kref, relay_destroy_channel);
}
@@ -411,14 +460,16 @@ void relay_close(struct rchan *chan)
void relay_flush(struct rchan *chan)
{
unsigned int i;
+ struct rchan_buf *prev = NULL;
if (!chan)
return;
for (i = 0; i < NR_CPUS; i++) {
- if (!chan->buf[i])
- continue;
+ if (!chan->buf[i] || chan->buf[i] == prev)
+ break;
relay_switch_subbuf(chan->buf[i], 0);
+ prev = chan->buf[i];
}
}
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