[PATCH 11/39] netfilter/x_tables: simplify ѕeq_file code

Christoph Hellwig
2018-04-19T12:41:12Z

Just use the address family from the proc private data instead of copying
it into per-file data.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
net/netfilter/x_tables.c | 39 +++++++++++----------------------------
1 file changed, 11 insertions(+), 28 deletions(-)

diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index 71325fef647d..3704101af27f 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -1489,15 +1489,10 @@ void *xt_unregister_table(struct xt_table *table)
EXPORT_SYMBOL_GPL(xt_unregister_table);

#ifdef CONFIG_PROC_FS
-struct xt_names_priv {
- struct seq_net_private p;
- u_int8_t af;
-};
static void *xt_table_seq_start(struct seq_file *seq, loff_t *pos)
{
- struct xt_names_priv *priv = seq->private;
struct net *net = seq_file_net(seq);
- u_int8_t af = priv->af;
+ u_int8_t af = (unsigned long)PDE_DATA(file_inode(seq->file));

mutex_lock(&xt[af].mutex);
return seq_list_start(&net->xt.tables[af], *pos);
@@ -1505,17 +1500,15 @@ static void *xt_table_seq_start(struct seq_file *seq, loff_t *pos)

static void *xt_table_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
- struct xt_names_priv *priv = seq->private;
struct net *net = seq_file_net(seq);
- u_int8_t af = priv->af;
+ u_int8_t af = (unsigned long)PDE_DATA(file_inode(seq->file));

return seq_list_next(v, &net->xt.tables[af], pos);
}

static void xt_table_seq_stop(struct seq_file *seq, void *v)
{
- struct xt_names_priv *priv = seq->private;
- u_int8_t af = priv->af;
+ u_int8_t af = (unsigned long)PDE_DATA(file_inode(seq->file));

mutex_unlock(&xt[af].mutex);
}
@@ -1538,16 +1531,8 @@ static const struct seq_operations xt_table_seq_ops = {

static int xt_table_open(struct inode *inode, struct file *file)
{
- int ret;
- struct xt_names_priv *priv;
-
- ret = seq_open_net(inode, file, &xt_table_seq_ops,
- sizeof(struct xt_names_priv));
- if (!ret) {
- priv = ((struct seq_file *)file->private_data)->private;
- priv->af = (unsigned long)PDE_DATA(inode);
- }
- return ret;
+ return seq_open_net(inode, file, &xt_table_seq_ops,
+ sizeof(struct seq_net_private));
}

static const struct file_operations xt_table_ops = {
@@ -1563,7 +1548,7 @@ static const struct file_operations xt_table_ops = {
*/
struct nf_mttg_trav {
struct list_head *head, *curr;
- uint8_t class, nfproto;
+ uint8_t class;
};

enum {
@@ -1580,6 +1565,7 @@ static void *xt_mttg_seq_next(struct seq_file *seq, void *v, loff_t *ppos,
[MTTG_TRAV_NFP_UNSPEC] = MTTG_TRAV_NFP_SPEC,
[MTTG_TRAV_NFP_SPEC] = MTTG_TRAV_DONE,
};
+ uint8_t nfproto = (unsigned long)PDE_DATA(file_inode(seq->file));
struct nf_mttg_trav *trav = seq->private;

switch (trav->class) {
@@ -1594,9 +1580,9 @@ static void *xt_mttg_seq_next(struct seq_file *seq, void *v, loff_t *ppos,
if (trav->curr != trav->head)
break;
mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
- mutex_lock(&xt[trav->nfproto].mutex);
+ mutex_lock(&xt[nfproto].mutex);
trav->head = trav->curr = is_target ?
- &xt[trav->nfproto].target : &xt[trav->nfproto].match;
+ &xt[nfproto].target : &xt[nfproto].match;
trav->class = next_class[trav->class];
break;
case MTTG_TRAV_NFP_SPEC:
@@ -1628,6 +1614,7 @@ static void *xt_mttg_seq_start(struct seq_file *seq, loff_t *pos,

static void xt_mttg_seq_stop(struct seq_file *seq, void *v)
{
+ uint8_t nfproto = (unsigned long)PDE_DATA(file_inode(seq->file));
struct nf_mttg_trav *trav = seq->private;

switch (trav->class) {
@@ -1635,7 +1622,7 @@ static void xt_mttg_seq_stop(struct seq_file *seq, void *v)
mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
break;
case MTTG_TRAV_NFP_SPEC:
- mutex_unlock(&xt[trav->nfproto].mutex);
+ mutex_unlock(&xt[nfproto].mutex);
break;
}
}
@@ -1680,8 +1667,6 @@ static int xt_match_open(struct inode *inode, struct file *file)
trav = __seq_open_private(file, &xt_match_seq_ops, sizeof(*trav));
if (!trav)
return -ENOMEM;
-
- trav->nfproto = (unsigned long)PDE_DATA(inode);
return 0;
}

@@ -1732,8 +1717,6 @@ static int xt_target_open(struct inode *inode, struct file *file)
trav = __seq_open_private(file, &xt_target_seq_ops, sizeof(*trav));
if (!trav)
return -ENOMEM;
-
- trav->nfproto = (unsigned long)PDE_DATA(inode);
return 0;
}

--
2.17.0

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