Commit 79a9d994 authored by Csaba Henk's avatar Csaba Henk Committed by Miklos Szeredi
Browse files

fuse: add fusectl interface to max_background



Make the max_background and congestion_threshold parameters of a FUSE
mount tunable at runtime by adding the respective knobs to its directory
within the fusectl filesystem.
Signed-off-by: default avatarCsaba Henk <csaba@gluster.com>
Signed-off-by: default avatarMiklos Szeredi <mszeredi@suse.cz>
parent 487ea5af
......@@ -61,6 +61,121 @@ static ssize_t fuse_conn_waiting_read(struct file *file, char __user *buf,
return simple_read_from_buffer(buf, len, ppos, tmp, size);
}
static ssize_t fuse_conn_limit_read(struct file *file, char __user *buf,
size_t len, loff_t *ppos, unsigned val)
{
char tmp[32];
size_t size = sprintf(tmp, "%u\n", val);
return simple_read_from_buffer(buf, len, ppos, tmp, size);
}
static ssize_t fuse_conn_limit_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos, unsigned *val,
unsigned global_limit)
{
unsigned long t;
char tmp[32];
unsigned limit = (1 << 16) - 1;
int err;
if (*ppos || count >= sizeof(tmp) - 1)
return -EINVAL;
if (copy_from_user(tmp, buf, count))
return -EINVAL;
tmp[count] = '\0';
err = strict_strtoul(tmp, 0, &t);
if (err)
return err;
if (!capable(CAP_SYS_ADMIN))
limit = min(limit, global_limit);
if (t > limit)
return -EINVAL;
*val = t;
return count;
}
static ssize_t fuse_conn_max_background_read(struct file *file,
char __user *buf, size_t len,
loff_t *ppos)
{
struct fuse_conn *fc;
unsigned val;
fc = fuse_ctl_file_conn_get(file);
if (!fc)
return 0;
val = fc->max_background;
fuse_conn_put(fc);
return fuse_conn_limit_read(file, buf, len, ppos, val);
}
static ssize_t fuse_conn_max_background_write(struct file *file,
const char __user *buf,
size_t count, loff_t *ppos)
{
unsigned val;
ssize_t ret;
ret = fuse_conn_limit_write(file, buf, count, ppos, &val,
max_user_bgreq);
if (ret > 0) {
struct fuse_conn *fc = fuse_ctl_file_conn_get(file);
if (fc) {
fc->max_background = val;
fuse_conn_put(fc);
}
}
return ret;
}
static ssize_t fuse_conn_congestion_threshold_read(struct file *file,
char __user *buf, size_t len,
loff_t *ppos)
{
struct fuse_conn *fc;
unsigned val;
fc = fuse_ctl_file_conn_get(file);
if (!fc)
return 0;
val = fc->congestion_threshold;
fuse_conn_put(fc);
return fuse_conn_limit_read(file, buf, len, ppos, val);
}
static ssize_t fuse_conn_congestion_threshold_write(struct file *file,
const char __user *buf,
size_t count, loff_t *ppos)
{
unsigned val;
ssize_t ret;
ret = fuse_conn_limit_write(file, buf, count, ppos, &val,
max_user_congthresh);
if (ret > 0) {
struct fuse_conn *fc = fuse_ctl_file_conn_get(file);
if (fc) {
fc->congestion_threshold = val;
fuse_conn_put(fc);
}
}
return ret;
}
static const struct file_operations fuse_ctl_abort_ops = {
.open = nonseekable_open,
.write = fuse_conn_abort_write,
......@@ -71,6 +186,18 @@ static const struct file_operations fuse_ctl_waiting_ops = {
.read = fuse_conn_waiting_read,
};
static const struct file_operations fuse_conn_max_background_ops = {
.open = nonseekable_open,
.read = fuse_conn_max_background_read,
.write = fuse_conn_max_background_write,
};
static const struct file_operations fuse_conn_congestion_threshold_ops = {
.open = nonseekable_open,
.read = fuse_conn_congestion_threshold_read,
.write = fuse_conn_congestion_threshold_write,
};
static struct dentry *fuse_ctl_add_dentry(struct dentry *parent,
struct fuse_conn *fc,
const char *name,
......@@ -127,9 +254,14 @@ int fuse_ctl_add_conn(struct fuse_conn *fc)
goto err;
if (!fuse_ctl_add_dentry(parent, fc, "waiting", S_IFREG | 0400, 1,
NULL, &fuse_ctl_waiting_ops) ||
NULL, &fuse_ctl_waiting_ops) ||
!fuse_ctl_add_dentry(parent, fc, "abort", S_IFREG | 0200, 1,
NULL, &fuse_ctl_abort_ops))
NULL, &fuse_ctl_abort_ops) ||
!fuse_ctl_add_dentry(parent, fc, "max_background", S_IFREG | 0600,
1, NULL, &fuse_conn_max_background_ops) ||
!fuse_ctl_add_dentry(parent, fc, "congestion_threshold",
S_IFREG | 0600, 1, NULL,
&fuse_conn_congestion_threshold_ops))
goto err;
return 0;
......
......@@ -32,7 +32,7 @@
#define FUSE_NAME_MAX 1024
/** Number of dentries for each connection in the control filesystem */
#define FUSE_CTL_NUM_DENTRIES 3
#define FUSE_CTL_NUM_DENTRIES 5
/** If the FUSE_DEFAULT_PERMISSIONS flag is given, the filesystem
module will check permissions based on the file mode. Otherwise no
......@@ -49,6 +49,10 @@ extern struct list_head fuse_conn_list;
/** Global mutex protecting fuse_conn_list and the control filesystem */
extern struct mutex fuse_mutex;
/** Module parameters */
extern unsigned max_user_bgreq;
extern unsigned max_user_congthresh;
/** FUSE inode */
struct fuse_inode {
/** Inode data */
......
......@@ -31,7 +31,7 @@ DEFINE_MUTEX(fuse_mutex);
static int set_global_limit(const char *val, struct kernel_param *kp);
static unsigned max_user_bgreq;
unsigned max_user_bgreq;
module_param_call(max_user_bgreq, set_global_limit, param_get_uint,
&max_user_bgreq, 0644);
__MODULE_PARM_TYPE(max_user_bgreq, "uint");
......@@ -39,7 +39,7 @@ MODULE_PARM_DESC(max_user_bgreq,
"Global limit for the maximum number of backgrounded requests an "
"unprivileged user can set");
static unsigned max_user_congthresh;
unsigned max_user_congthresh;
module_param_call(max_user_congthresh, set_global_limit, param_get_uint,
&max_user_congthresh, 0644);
__MODULE_PARM_TYPE(max_user_congthresh, "uint");
......
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