Many places in kernel use seq_file API to iterate over a regular
list_head. The code for such iteration is identical in all the
places, so it's worth introducing a common helpers.
This makes code about 300 lines smaller:
block/genhd.c | 40 +++-----
crypto/proc.c | 17 ---
drivers/char/misc.c | 18 ----
drivers/input/input.c | 29 ------
drivers/isdn/capi/kcapi_proc.c | 28 ------
fs/afs/proc.c | 81 ++----------------
fs/namespace.c | 14 ---
fs/nfs/client.c | 54 +-----------
fs/proc/proc_tty.c | 15 ---
fs/seq_file.c | 34 +++++++
include/linux/seq_file.h | 11 ++
kernel/module.c | 17 ---
mm/slab.c | 28 +-----
net/atm/br2684.c | 22 ----
net/core/sock.c | 39 --------
net/ipv4/netfilter/nf_conntrack_l3proto_ipv4_compat.c | 27 ------
net/netfilter/nf_conntrack_expect.c | 27 ------
net/rxrpc/ar-proc.c | 48 +---------
18 files changed, 126 insertions(+), 423 deletions(-)
The first version of this patch made the helper functions static inline
in the seq_file.h header. This patch moves them to the fs/seq_file.c as
Andrew proposed. The vmlinux .text section sizes are as follows:
2.6.22-rc1-mm1: 0x001794d5
with the previous version: 0x00179505
with this patch: 0x00179135
The config file used was make allnoconfig with the "y" inclusion of all
the possible options to make the files modified by the patch compile plus
drivers I have on the test node.
Many places in kernel use seq_file API to iterate over a regular
list_head. The code for such iteration is identical in all the
places, so it's worth introducing a common helpers.
Signed-off-by: Pavel Emelianov <[email protected]>
---
diff --git a/fs/seq_file.c b/fs/seq_file.c
index 0ac22af..49194a4 100644
--- a/fs/seq_file.c
+++ b/fs/seq_file.c
@@ -447,3 +447,37 @@ int seq_puts(struct seq_file *m, const c
return -1;
}
EXPORT_SYMBOL(seq_puts);
+
+struct list_head *seq_list_start(struct list_head *head, loff_t pos)
+{
+ struct list_head *lh;
+
+ list_for_each(lh, head)
+ if (pos-- == 0)
+ return lh;
+
+ return NULL;
+}
+
+EXPORT_SYMBOL(seq_list_start);
+
+struct list_head *seq_list_start_head(struct list_head *head, loff_t pos)
+{
+ if (!pos)
+ return head;
+
+ return seq_list_start(head, pos - 1);
+}
+
+EXPORT_SYMBOL(seq_list_start_head);
+
+struct list_head *seq_list_next(void *v, struct list_head *head, loff_t *ppos)
+{
+ struct list_head *lh;
+
+ lh = ((struct list_head *)v)->next;
+ ++*ppos;
+ return lh == head ? NULL : lh;
+}
+
+EXPORT_SYMBOL(seq_list_next);
diff --git a/include/linux/seq_file.h b/include/linux/seq_file.h
index 3e3cccb..83783ab 100644
--- a/include/linux/seq_file.h
+++ b/include/linux/seq_file.h
@@ -50,5 +50,16 @@ int seq_release_private(struct inode *,
#define SEQ_START_TOKEN ((void *)1)
+/*
+ * Helpers for iteration over list_head-s in seq_files
+ */
+
+extern struct list_head *seq_list_start(struct list_head *head,
+ loff_t pos);
+extern struct list_head *seq_list_start_head(struct list_head *head,
+ loff_t pos);
+extern struct list_head *seq_list_next(void *v, struct list_head *head,
+ loff_t *ppos);
+
#endif
#endif
These proc files show some header before dumping
the list, so the seq_list_start_head() is used.
Signed-off-by: Pavel Emelianov <[email protected]>
---
diff --git a/fs/afs/proc.c b/fs/afs/proc.c
index d5601f6..d5300e4 100644
--- a/fs/afs/proc.c
+++ b/fs/afs/proc.c
@@ -200,23 +200,9 @@ static int afs_proc_cells_open(struct in
*/
static void *afs_proc_cells_start(struct seq_file *m, loff_t *_pos)
{
- struct list_head *_p;
- loff_t pos = *_pos;
-
/* lock the list against modification */
down_read(&afs_proc_cells_sem);
-
- /* allow for the header line */
- if (!pos)
- return (void *) 1;
- pos--;
-
- /* find the n'th element in the list */
- list_for_each(_p, &afs_proc_cells)
- if (!pos--)
- break;
-
- return _p != &afs_proc_cells ? _p : NULL;
+ return seq_list_start_head(&afs_proc_cells, *_pos);
}
/*
@@ -224,14 +210,7 @@ static void *afs_proc_cells_start(struct
*/
static void *afs_proc_cells_next(struct seq_file *p, void *v, loff_t *pos)
{
- struct list_head *_p;
-
- (*pos)++;
-
- _p = v;
- _p = v == (void *) 1 ? afs_proc_cells.next : _p->next;
-
- return _p != &afs_proc_cells ? _p : NULL;
+ return seq_list_next(v, &afs_proc_cells, pos);
}
/*
@@ -249,7 +228,7 @@ static int afs_proc_cells_show(struct se
{
struct afs_cell *cell = list_entry(v, struct afs_cell, proc_link);
- if (v == (void *) 1) {
+ if (v == &afs_proc_cells) {
/* display header on line 1 */
seq_puts(m, "USE NAME\n");
return 0;
@@ -502,26 +481,13 @@ static int afs_proc_cell_volumes_release
*/
static void *afs_proc_cell_volumes_start(struct seq_file *m, loff_t *_pos)
{
- struct list_head *_p;
struct afs_cell *cell = m->private;
- loff_t pos = *_pos;
_enter("cell=%p pos=%Ld", cell, *_pos);
/* lock the list against modification */
down_read(&cell->vl_sem);
-
- /* allow for the header line */
- if (!pos)
- return (void *) 1;
- pos--;
-
- /* find the n'th element in the list */
- list_for_each(_p, &cell->vl_list)
- if (!pos--)
- break;
-
- return _p != &cell->vl_list ? _p : NULL;
+ return seq_list_start_head(&cell->vl_list, *_pos);
}
/*
@@ -530,17 +496,10 @@ static void *afs_proc_cell_volumes_start
static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
loff_t *_pos)
{
- struct list_head *_p;
struct afs_cell *cell = p->private;
_enter("cell=%p pos=%Ld", cell, *_pos);
-
- (*_pos)++;
-
- _p = v;
- _p = (v == (void *) 1) ? cell->vl_list.next : _p->next;
-
- return (_p != &cell->vl_list) ? _p : NULL;
+ return seq_list_next(v, &cell->vl_list, _pos);
}
/*
@@ -568,11 +527,12 @@ const char afs_vlocation_states[][4] = {
*/
static int afs_proc_cell_volumes_show(struct seq_file *m, void *v)
{
+ struct afs_cell *cell = m->private;
struct afs_vlocation *vlocation =
list_entry(v, struct afs_vlocation, link);
/* display header on line 1 */
- if (v == (void *) 1) {
+ if (v == &cell->vl_list) {
seq_puts(m, "USE STT VLID[0] VLID[1] VLID[2] NAME\n");
return 0;
}
@@ -733,26 +693,13 @@ static int afs_proc_cell_servers_release
static void *afs_proc_cell_servers_start(struct seq_file *m, loff_t *_pos)
__acquires(m->private->servers_lock)
{
- struct list_head *_p;
struct afs_cell *cell = m->private;
- loff_t pos = *_pos;
_enter("cell=%p pos=%Ld", cell, *_pos);
/* lock the list against modification */
read_lock(&cell->servers_lock);
-
- /* allow for the header line */
- if (!pos)
- return (void *) 1;
- pos--;
-
- /* find the n'th element in the list */
- list_for_each(_p, &cell->servers)
- if (!pos--)
- break;
-
- return _p != &cell->servers ? _p : NULL;
+ return seq_list_start_head(&cell->servers, *_pos);
}
/*
@@ -761,17 +708,10 @@ static void *afs_proc_cell_servers_start
static void *afs_proc_cell_servers_next(struct seq_file *p, void *v,
loff_t *_pos)
{
- struct list_head *_p;
struct afs_cell *cell = p->private;
_enter("cell=%p pos=%Ld", cell, *_pos);
-
- (*_pos)++;
-
- _p = v;
- _p = v == (void *) 1 ? cell->servers.next : _p->next;
-
- return _p != &cell->servers ? _p : NULL;
+ return seq_list_next(v, &cell->servers, _pos);
}
/*
@@ -790,11 +730,12 @@ static void afs_proc_cell_servers_stop(s
*/
static int afs_proc_cell_servers_show(struct seq_file *m, void *v)
{
+ struct afs_cell *cell = m->private;
struct afs_server *server = list_entry(v, struct afs_server, link);
char ipaddr[20];
/* display header on line 1 */
- if (v == (void *) 1) {
+ if (v == &cell->servers) {
seq_puts(m, "USE ADDR STATE\n");
return 0;
}
The .show callback receives the list_head pointer now, not
the struct br2684_dev one.
Signed-off-by: Pavel Emelianov <[email protected]>
---
diff --git a/net/atm/br2684.c b/net/atm/br2684.c
index 0e9f00c..3e26438 100644
--- a/net/atm/br2684.c
+++ b/net/atm/br2684.c
@@ -699,28 +699,13 @@ static struct atm_ioctl br2684_ioctl_ops
#ifdef CONFIG_PROC_FS
static void *br2684_seq_start(struct seq_file *seq, loff_t *pos)
{
- loff_t offs = 0;
- struct br2684_dev *brd;
-
read_lock(&devs_lock);
-
- list_for_each_entry(brd, &br2684_devs, br2684_devs) {
- if (offs == *pos)
- return brd;
- ++offs;
- }
- return NULL;
+ return seq_list_start(&br2684_devs, *pos);
}
static void *br2684_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
- struct br2684_dev *brd = v;
-
- ++*pos;
-
- brd = list_entry(brd->br2684_devs.next,
- struct br2684_dev, br2684_devs);
- return (&brd->br2684_devs != &br2684_devs) ? brd : NULL;
+ return seq_list_next(v, &br2684_devs, pos);
}
static void br2684_seq_stop(struct seq_file *seq, void *v)
@@ -730,7 +715,8 @@ static void br2684_seq_stop(struct seq_f
static int br2684_seq_show(struct seq_file *seq, void *v)
{
- const struct br2684_dev *brdev = v;
+ const struct br2684_dev *brdev = list_entry(v, struct br2684_dev,
+ br2684_devs);
const struct net_device *net_dev = brdev->net_dev;
const struct br2684_vcc *brvcc;
The /proc/partitions .show callback checked the *v to be
the first element in list to show the header. Now *v is the
struct list_head pointer and it is checked for the head of
the list.
The comment in /proc/diskstats .show handler is also updated
not to forget it in the future.
Signed-off-by: Pavel Emelianov <[email protected]>
---
diff --git a/block/genhd.c b/block/genhd.c
index 863a8c0..8813c14 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -270,22 +270,13 @@ void __init printk_all_partitions(void)
/* iterator */
static void *part_start(struct seq_file *part, loff_t *pos)
{
- struct list_head *p;
- loff_t l = *pos;
-
mutex_lock(&block_subsys_lock);
- list_for_each(p, &block_subsys.list)
- if (!l--)
- return list_entry(p, struct gendisk, kobj.entry);
- return NULL;
+ return seq_list_start_head(&block_subsys.list, *pos);
}
static void *part_next(struct seq_file *part, void *v, loff_t *pos)
{
- struct list_head *p = ((struct gendisk *)v)->kobj.entry.next;
- ++*pos;
- return p==&block_subsys.list ? NULL :
- list_entry(p, struct gendisk, kobj.entry);
+ return seq_list_next(v, &block_subsys.list, pos);
}
static void part_stop(struct seq_file *part, void *v)
@@ -295,13 +286,16 @@ static void part_stop(struct seq_file *p
static int show_partition(struct seq_file *part, void *v)
{
- struct gendisk *sgp = v;
+ struct gendisk *sgp;
int n;
char buf[BDEVNAME_SIZE];
- if (&sgp->kobj.entry == block_subsys.list.next)
+ if (v == &block_subsys.list) {
seq_puts(part, "major minor #blocks name\n\n");
+ return 0;
+ }
+ sgp = list_entry(v, struct gendisk, kobj.entry);
/* Don't show non-partitionable removeable devices or empty devices */
if (!get_capacity(sgp) ||
(sgp->minors == 1 && (sgp->flags & GENHD_FL_REMOVABLE)))
@@ -622,22 +616,13 @@ decl_subsys(block, &ktype_block, &block_
/* iterator */
static void *diskstats_start(struct seq_file *part, loff_t *pos)
{
- loff_t k = *pos;
- struct list_head *p;
-
mutex_lock(&block_subsys_lock);
- list_for_each(p, &block_subsys.list)
- if (!k--)
- return list_entry(p, struct gendisk, kobj.entry);
- return NULL;
+ return seq_list_start(&block_subsys.list, *pos);
}
static void *diskstats_next(struct seq_file *part, void *v, loff_t *pos)
{
- struct list_head *p = ((struct gendisk *)v)->kobj.entry.next;
- ++*pos;
- return p==&block_subsys.list ? NULL :
- list_entry(p, struct gendisk, kobj.entry);
+ return seq_list_next(v, &block_subsys.list, pos);
}
static void diskstats_stop(struct seq_file *part, void *v)
@@ -647,18 +632,21 @@ static void diskstats_stop(struct seq_fi
static int diskstats_show(struct seq_file *s, void *v)
{
- struct gendisk *gp = v;
+ struct gendisk *gp;
char buf[BDEVNAME_SIZE];
int n = 0;
/*
- if (&sgp->kobj.entry == block_subsys.kset.list.next)
+ if (v == &block_subsys.list) {
seq_puts(s, "major minor name"
" rio rmerge rsect ruse wio wmerge "
"wsect wuse running use aveq"
"\n\n");
+ return 0;
+ }
*/
+ gp = list_entry(v, struct gendisk, kobj.entry);
preempt_disable();
disk_round_stats(gp);
preempt_enable();
Simple and stupid - just use the same code from another
place in the kernel.
Signed-off-by: Pavel Emelianov <[email protected]>
---
diff --git a/crypto/proc.c b/crypto/proc.c
index 102c751..3d73323 100644
--- a/crypto/proc.c
+++ b/crypto/proc.c
@@ -23,24 +23,13 @@
static void *c_start(struct seq_file *m, loff_t *pos)
{
- struct list_head *v;
- loff_t n = *pos;
-
down_read(&crypto_alg_sem);
- list_for_each(v, &crypto_alg_list)
- if (!n--)
- return list_entry(v, struct crypto_alg, cra_list);
- return NULL;
+ return seq_list_start(&crypto_alg_list, *pos);
}
static void *c_next(struct seq_file *m, void *p, loff_t *pos)
{
- struct list_head *v = p;
-
- (*pos)++;
- v = v->next;
- return (v == &crypto_alg_list) ?
- NULL : list_entry(v, struct crypto_alg, cra_list);
+ return seq_list_next(p, &crypto_alg_list, pos);
}
static void c_stop(struct seq_file *m, void *p)
@@ -50,7 +39,7 @@ static void c_stop(struct seq_file *m, v
static int c_show(struct seq_file *m, void *p)
{
- struct crypto_alg *alg = (struct crypto_alg *)p;
+ struct crypto_alg *alg = list_entry(p, struct crypto_alg, cra_list);
seq_printf(m, "name : %s\n", alg->cra_name);
seq_printf(m, "driver : %s\n", alg->cra_driver_name);
This is essentially just a renaming of the existing
functions as the seq_list_start() and seq_list_next()
copies already exist in the input.c file. Now we have
them in the generic place.
Signed-off-by: Pavel Emelianov <[email protected]>
---
diff --git a/drivers/input/input.c b/drivers/input/input.c
index ccd8aba..da83c17 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -471,37 +471,16 @@ static unsigned int input_proc_devices_p
return 0;
}
-static struct list_head *list_get_nth_element(struct list_head *list, loff_t *pos)
-{
- struct list_head *node;
- loff_t i = 0;
-
- list_for_each(node, list)
- if (i++ == *pos)
- return node;
-
- return NULL;
-}
-
-static struct list_head *list_get_next_element(struct list_head *list, struct list_head *element, loff_t *pos)
-{
- if (element->next == list)
- return NULL;
-
- ++(*pos);
- return element->next;
-}
-
static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
{
/* acquire lock here ... Yes, we do need locking, I knowi, I know... */
- return list_get_nth_element(&input_dev_list, pos);
+ return seq_list_start(&input_dev_list, *pos);
}
static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
- return list_get_next_element(&input_dev_list, v, pos);
+ return seq_list_next(v, &input_dev_list, pos);
}
static void input_devices_seq_stop(struct seq_file *seq, void *v)
@@ -592,13 +571,13 @@ static void *input_handlers_seq_start(st
{
/* acquire lock here ... Yes, we do need locking, I knowi, I know... */
seq->private = (void *)(unsigned long)*pos;
- return list_get_nth_element(&input_handler_list, pos);
+ return seq_list_start(&input_handler_list, *pos);
}
static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
seq->private = (void *)(unsigned long)(*pos + 1);
- return list_get_next_element(&input_handler_list, v, pos);
+ return seq_list_next(v, &input_handler_list, pos);
}
static void input_handlers_seq_stop(struct seq_file *seq, void *v)
The similar code exists here and is called capi_driver_get_idx().
Use generic helpers now and remember to convert list_head to
struct capi_driver in .show callback.
Signed-off-by: Pavel Emelianov <[email protected]>
---
diff --git a/drivers/isdn/capi/kcapi_proc.c b/drivers/isdn/capi/kcapi_proc.c
index 31f4fd8..845a797 100644
--- a/drivers/isdn/capi/kcapi_proc.c
+++ b/drivers/isdn/capi/kcapi_proc.c
@@ -243,36 +243,15 @@ create_seq_entry(char *name, mode_t mode
// ---------------------------------------------------------------------------
-
-static __inline__ struct capi_driver *capi_driver_get_idx(loff_t pos)
-{
- struct capi_driver *drv = NULL;
- struct list_head *l;
- loff_t i;
-
- i = 0;
- list_for_each(l, &capi_drivers) {
- drv = list_entry(l, struct capi_driver, list);
- if (i++ == pos)
- return drv;
- }
- return NULL;
-}
-
static void *capi_driver_start(struct seq_file *seq, loff_t *pos)
{
- struct capi_driver *drv;
read_lock(&capi_drivers_list_lock);
- drv = capi_driver_get_idx(*pos);
- return drv;
+ return seq_list_start(&capi_drivers, *pos);
}
static void *capi_driver_next(struct seq_file *seq, void *v, loff_t *pos)
{
- struct capi_driver *drv = (struct capi_driver *)v;
- ++*pos;
- if (drv->list.next == &capi_drivers) return NULL;
- return list_entry(drv->list.next, struct capi_driver, list);
+ return seq_list_next(v, &capi_drivers, pos);
}
static void capi_driver_stop(struct seq_file *seq, void *v)
@@ -282,7 +261,8 @@ static void capi_driver_stop(struct seq_
static int capi_driver_show(struct seq_file *seq, void *v)
{
- struct capi_driver *drv = (struct capi_driver *)v;
+ struct capi_driver *drv = list_entry(v, struct capi_driver, list);
+
seq_printf(seq, "%-32s %s\n", drv->name, drv->revision);
return 0;
}
Simple and stupid - just use the helpers.
Sorry for no maintainer in Cc: - I haven't found any.
Signed-off-by: Pavel Emelianov <[email protected]>
---
diff --git a/drivers/char/misc.c b/drivers/char/misc.c
index 4e6fb96..71c8cd7 100644
--- a/drivers/char/misc.c
+++ b/drivers/char/misc.c
@@ -67,25 +67,13 @@ extern int pmu_device_init(void);
#ifdef CONFIG_PROC_FS
static void *misc_seq_start(struct seq_file *seq, loff_t *pos)
{
- struct miscdevice *p;
- loff_t off = 0;
-
mutex_lock(&misc_mtx);
- list_for_each_entry(p, &misc_list, list) {
- if (*pos == off++)
- return p;
- }
- return NULL;
+ return seq_list_start(&misc_list, *pos);
}
static void *misc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
- struct list_head *n = ((struct miscdevice *)v)->list.next;
-
- ++*pos;
-
- return (n != &misc_list) ? list_entry(n, struct miscdevice, list)
- : NULL;
+ return seq_list_next(v, &misc_list, pos);
}
static void misc_seq_stop(struct seq_file *seq, void *v)
@@ -95,7 +83,7 @@ static void misc_seq_stop(struct seq_fil
static int misc_seq_show(struct seq_file *seq, void *v)
{
- const struct miscdevice *p = v;
+ const struct miscdevice *p = list_entry(v, struct miscdevice, list);
seq_printf(seq, "%3i %s\n", p->minor, p->name ? p->name : "");
return 0;
Here there is not need even in .show callback altering.
The original code passes list_head in *v.
Signed-off-by: Pavel Emelianov <[email protected]>
---
diff --git a/kernel/module.c b/kernel/module.c
index 015d60c..7a1a4d3 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2232,26 +2232,13 @@ unsigned long module_kallsyms_lookup_nam
/* Called by the /proc file system to return a list of modules. */
static void *m_start(struct seq_file *m, loff_t *pos)
{
- struct list_head *i;
- loff_t n = 0;
-
mutex_lock(&module_mutex);
- list_for_each(i, &modules) {
- if (n++ == *pos)
- break;
- }
- if (i == &modules)
- return NULL;
- return i;
+ return seq_list_start(&modules, *pos);
}
static void *m_next(struct seq_file *m, void *p, loff_t *pos)
{
- struct list_head *i = p;
- (*pos)++;
- if (i->next == &modules)
- return NULL;
- return i->next;
+ return seq_list_next(p, &modules, pos);
}
static void m_stop(struct seq_file *m, void *p)
This includes /proc/net/protocols, /proc/net/rxrpc_calls
and /proc/net/rxrpc_connections files.
All three need seq_list_start_head to show some header.
Signed-off-by: Pavel Emelianov <[email protected]>
---
diff --git a/net/core/sock.c b/net/core/sock.c
index 22183c2..528f65b 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1839,46 +1839,15 @@ void proto_unregister(struct proto *prot
EXPORT_SYMBOL(proto_unregister);
#ifdef CONFIG_PROC_FS
-static inline struct proto *__proto_head(void)
-{
- return list_entry(proto_list.next, struct proto, node);
-}
-
-static inline struct proto *proto_head(void)
-{
- return list_empty(&proto_list) ? NULL : __proto_head();
-}
-
-static inline struct proto *proto_next(struct proto *proto)
-{
- return proto->node.next == &proto_list ? NULL :
- list_entry(proto->node.next, struct proto, node);
-}
-
-static inline struct proto *proto_get_idx(loff_t pos)
-{
- struct proto *proto;
- loff_t i = 0;
-
- list_for_each_entry(proto, &proto_list, node)
- if (i++ == pos)
- goto out;
-
- proto = NULL;
-out:
- return proto;
-}
-
static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
{
read_lock(&proto_list_lock);
- return *pos ? proto_get_idx(*pos - 1) : SEQ_START_TOKEN;
+ return seq_list_start_head(&proto_list, *pos);
}
static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
- ++*pos;
- return v == SEQ_START_TOKEN ? proto_head() : proto_next(v);
+ return seq_list_next(v, &proto_list, pos);
}
static void proto_seq_stop(struct seq_file *seq, void *v)
@@ -1926,7 +1895,7 @@ static void proto_seq_printf(struct seq_
static int proto_seq_show(struct seq_file *seq, void *v)
{
- if (v == SEQ_START_TOKEN)
+ if (v == &proto_list)
seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
"protocol",
"size",
@@ -1938,7 +1907,7 @@ static int proto_seq_show(struct seq_fil
"module",
"cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
else
- proto_seq_printf(seq, v);
+ proto_seq_printf(seq, list_entry(v, struct proto, node));
return 0;
}
diff --git a/net/rxrpc/ar-proc.c b/net/rxrpc/ar-proc.c
index 1c0be0e..56a5317 100644
--- a/net/rxrpc/ar-proc.c
+++ b/net/rxrpc/ar-proc.c
@@ -30,31 +30,13 @@ static const char *rxrpc_conn_states[] =
*/
static void *rxrpc_call_seq_start(struct seq_file *seq, loff_t *_pos)
{
- struct list_head *_p;
- loff_t pos = *_pos;
-
read_lock(&rxrpc_call_lock);
- if (!pos)
- return SEQ_START_TOKEN;
- pos--;
-
- list_for_each(_p, &rxrpc_calls)
- if (!pos--)
- break;
-
- return _p != &rxrpc_calls ? _p : NULL;
+ return seq_list_start_head(&rxrpc_calls, *_pos);
}
static void *rxrpc_call_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
- struct list_head *_p;
-
- (*pos)++;
-
- _p = v;
- _p = (v == SEQ_START_TOKEN) ? rxrpc_calls.next : _p->next;
-
- return _p != &rxrpc_calls ? _p : NULL;
+ return seq_list_next(v, &rxrpc_calls, pos);
}
static void rxrpc_call_seq_stop(struct seq_file *seq, void *v)
@@ -68,7 +50,7 @@ static int rxrpc_call_seq_show(struct se
struct rxrpc_call *call;
char lbuff[4 + 4 + 4 + 4 + 5 + 1], rbuff[4 + 4 + 4 + 4 + 5 + 1];
- if (v == SEQ_START_TOKEN) {
+ if (v == &rxrpc_calls) {
seq_puts(seq,
"Proto Local Remote "
" SvID ConnID CallID End Use State Abort "
@@ -129,32 +111,14 @@ struct file_operations rxrpc_call_seq_fo
*/
static void *rxrpc_connection_seq_start(struct seq_file *seq, loff_t *_pos)
{
- struct list_head *_p;
- loff_t pos = *_pos;
-
read_lock(&rxrpc_connection_lock);
- if (!pos)
- return SEQ_START_TOKEN;
- pos--;
-
- list_for_each(_p, &rxrpc_connections)
- if (!pos--)
- break;
-
- return _p != &rxrpc_connections ? _p : NULL;
+ return seq_list_start_head(&rxrpc_connections, *_pos);
}
static void *rxrpc_connection_seq_next(struct seq_file *seq, void *v,
loff_t *pos)
{
- struct list_head *_p;
-
- (*pos)++;
-
- _p = v;
- _p = (v == SEQ_START_TOKEN) ? rxrpc_connections.next : _p->next;
-
- return _p != &rxrpc_connections ? _p : NULL;
+ return seq_list_next(v, &rxrpc_connections, pos);
}
static void rxrpc_connection_seq_stop(struct seq_file *seq, void *v)
@@ -168,7 +132,7 @@ static int rxrpc_connection_seq_show(str
struct rxrpc_transport *trans;
char lbuff[4 + 4 + 4 + 4 + 5 + 1], rbuff[4 + 4 + 4 + 4 + 5 + 1];
- if (v == SEQ_START_TOKEN) {
+ if (v == &rxrpc_connections) {
seq_puts(seq,
"Proto Local Remote "
" SvID ConnID Calls End Use State Key "
This includes /proc/net/ip_conntrack_expect file.
Although struct nf_conntrack_expect has list_head as
the very first element I use list_entry in .show callback
to emphasize the fact that *v is the list_head pointer.
Signed-off-by: Pavel Emelianov <[email protected]>
---
diff --git a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4_compat.c b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4_compat.c
index 89f933e..bec843a 100644
--- a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4_compat.c
+++ b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4_compat.c
@@ -208,35 +208,15 @@ static const struct file_operations ct_f
/* expects */
static void *exp_seq_start(struct seq_file *s, loff_t *pos)
{
- struct list_head *e = &nf_conntrack_expect_list;
- loff_t i;
-
/* strange seq_file api calls stop even if we fail,
* thus we need to grab lock since stop unlocks */
read_lock_bh(&nf_conntrack_lock);
-
- if (list_empty(e))
- return NULL;
-
- for (i = 0; i <= *pos; i++) {
- e = e->next;
- if (e == &nf_conntrack_expect_list)
- return NULL;
- }
- return e;
+ return seq_list_start(&nf_conntrack_expect_list, *pos);
}
static void *exp_seq_next(struct seq_file *s, void *v, loff_t *pos)
{
- struct list_head *e = v;
-
- ++*pos;
- e = e->next;
-
- if (e == &nf_conntrack_expect_list)
- return NULL;
-
- return e;
+ return seq_list_next(v, &nf_conntrack_expect_list, pos);
}
static void exp_seq_stop(struct seq_file *s, void *v)
@@ -246,7 +226,8 @@ static void exp_seq_stop(struct seq_file
static int exp_seq_show(struct seq_file *s, void *v)
{
- struct nf_conntrack_expect *exp = v;
+ struct nf_conntrack_expect *exp = list_entry(v,
+ struct nf_conntrack_expect, list);
if (exp->tuple.src.l3num != AF_INET)
return 0;
diff --git a/net/netfilter/nf_conntrack_expect.c b/net/netfilter/nf_conntrack_expect.c
index 117cbfd..7ea80e4 100644
--- a/net/netfilter/nf_conntrack_expect.c
+++ b/net/netfilter/nf_conntrack_expect.c
@@ -366,35 +366,15 @@ EXPORT_SYMBOL_GPL(nf_conntrack_expect_re
#ifdef CONFIG_PROC_FS
static void *exp_seq_start(struct seq_file *s, loff_t *pos)
{
- struct list_head *e = &nf_conntrack_expect_list;
- loff_t i;
-
/* strange seq_file api calls stop even if we fail,
* thus we need to grab lock since stop unlocks */
read_lock_bh(&nf_conntrack_lock);
-
- if (list_empty(e))
- return NULL;
-
- for (i = 0; i <= *pos; i++) {
- e = e->next;
- if (e == &nf_conntrack_expect_list)
- return NULL;
- }
- return e;
+ return seq_list_start(&nf_conntrack_expect_list, *pos);
}
static void *exp_seq_next(struct seq_file *s, void *v, loff_t *pos)
{
- struct list_head *e = v;
-
- ++*pos;
- e = e->next;
-
- if (e == &nf_conntrack_expect_list)
- return NULL;
-
- return e;
+ return seq_list_next(v, &nf_conntrack_expect_list, pos);
}
static void exp_seq_stop(struct seq_file *s, void *v)
@@ -404,7 +384,8 @@ static void exp_seq_stop(struct seq_file
static int exp_seq_show(struct seq_file *s, void *v)
{
- struct nf_conntrack_expect *expect = v;
+ struct nf_conntrack_expect *expect = list_entry(v,
+ struct nf_conntrack_expect, list);
if (expect->timeout.function)
seq_printf(s, "%ld ", timer_pending(&expect->timeout)
This includes /proc/fs/nfsfs/servers and /proc/fs/nfsfs/volumes
entries.
Both need to show the header and use the list_head.
Signed-off-by: Pavel Emelianov <[email protected]>
---
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 50c6821..10355ec 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -1232,23 +1232,9 @@ static int nfs_server_list_open(struct i
*/
static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
{
- struct list_head *_p;
- loff_t pos = *_pos;
-
/* lock the list against modification */
spin_lock(&nfs_client_lock);
-
- /* allow for the header line */
- if (!pos)
- return SEQ_START_TOKEN;
- pos--;
-
- /* find the n'th element in the list */
- list_for_each(_p, &nfs_client_list)
- if (!pos--)
- break;
-
- return _p != &nfs_client_list ? _p : NULL;
+ return seq_list_start_head(&nfs_client_list, *_pos);
}
/*
@@ -1256,14 +1242,7 @@ static void *nfs_server_list_start(struc
*/
static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
{
- struct list_head *_p;
-
- (*pos)++;
-
- _p = v;
- _p = (v == SEQ_START_TOKEN) ? nfs_client_list.next : _p->next;
-
- return _p != &nfs_client_list ? _p : NULL;
+ return seq_list_next(v, &nfs_client_list, pos);
}
/*
@@ -1282,7 +1261,7 @@ static int nfs_server_list_show(struct s
struct nfs_client *clp;
/* display header on line 1 */
- if (v == SEQ_START_TOKEN) {
+ if (v == &nfs_client_list) {
seq_puts(m, "NV SERVER PORT USE HOSTNAME\n");
return 0;
}
@@ -1323,23 +1302,9 @@ static int nfs_volume_list_open(struct i
*/
static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
{
- struct list_head *_p;
- loff_t pos = *_pos;
-
/* lock the list against modification */
spin_lock(&nfs_client_lock);
-
- /* allow for the header line */
- if (!pos)
- return SEQ_START_TOKEN;
- pos--;
-
- /* find the n'th element in the list */
- list_for_each(_p, &nfs_volume_list)
- if (!pos--)
- break;
-
- return _p != &nfs_volume_list ? _p : NULL;
+ return seq_list_start_head(&nfs_volume_list, *_pos);
}
/*
@@ -1347,14 +1312,7 @@ static void *nfs_volume_list_start(struc
*/
static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
{
- struct list_head *_p;
-
- (*pos)++;
-
- _p = v;
- _p = (v == SEQ_START_TOKEN) ? nfs_volume_list.next : _p->next;
-
- return _p != &nfs_volume_list ? _p : NULL;
+ return seq_list_next(v, &nfs_volume_list, pos);
}
/*
@@ -1375,7 +1333,7 @@ static int nfs_volume_list_show(struct s
char dev[8], fsid[17];
/* display header on line 1 */
- if (v == SEQ_START_TOKEN) {
+ if (v == &nfs_volume_list) {
seq_puts(m, "NV SERVER PORT DEV FSID\n");
return 0;
}
Simple and stupid like some previous ones. Just use new API.
Signed-off-by: Pavel Emelianov <[email protected]>
---
diff --git a/fs/proc/proc_tty.c b/fs/proc/proc_tty.c
index b3a473b..2284622 100644
--- a/fs/proc/proc_tty.c
+++ b/fs/proc/proc_tty.c
@@ -69,7 +69,7 @@ static void show_tty_range(struct seq_fi
static int show_tty_driver(struct seq_file *m, void *v)
{
- struct tty_driver *p = v;
+ struct tty_driver *p = list_entry(v, struct tty_driver, tty_drivers);
dev_t from = MKDEV(p->major, p->minor_start);
dev_t to = from + p->num;
@@ -106,22 +106,13 @@ static int show_tty_driver(struct seq_fi
/* iterator */
static void *t_start(struct seq_file *m, loff_t *pos)
{
- struct list_head *p;
- loff_t l = *pos;
-
mutex_lock(&tty_mutex);
- list_for_each(p, &tty_drivers)
- if (!l--)
- return list_entry(p, struct tty_driver, tty_drivers);
- return NULL;
+ return seq_list_start(&tty_drivers, *pos);
}
static void *t_next(struct seq_file *m, void *v, loff_t *pos)
{
- struct list_head *p = ((struct tty_driver *)v)->tty_drivers.next;
- (*pos)++;
- return p==&tty_drivers ? NULL :
- list_entry(p, struct tty_driver, tty_drivers);
+ return seq_list_next(v, &tty_drivers, pos);
}
static void t_stop(struct seq_file *m, void *v)
Pavel Emelianov <[email protected]> wrote:
> Many places in kernel use seq_file API to iterate over a regular
> list_head. The code for such iteration is identical in all the
> places, so it's worth introducing a common helpers.
And the documentation for this?
David
This entry prints a header in .start callback. This is OK,
but the more elegant solution would be to move this into the
.show callback and use seq_list_start_head() in .start one.
I have left it as is in order to make the patch just switch
to new API and noting more.
Signed-off-by: Pavel Emelianov <[email protected]>
---
diff --git a/mm/slab.c b/mm/slab.c
index 6edfd34..faad0d7 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -4161,26 +4161,17 @@ static void print_slabinfo_header(struct
static void *s_start(struct seq_file *m, loff_t *pos)
{
loff_t n = *pos;
- struct list_head *p;
mutex_lock(&cache_chain_mutex);
if (!n)
print_slabinfo_header(m);
- p = cache_chain.next;
- while (n--) {
- p = p->next;
- if (p == &cache_chain)
- return NULL;
- }
- return list_entry(p, struct kmem_cache, next);
+
+ return seq_list_start(&cache_chain, *pos);
}
static void *s_next(struct seq_file *m, void *p, loff_t *pos)
{
- struct kmem_cache *cachep = p;
- ++*pos;
- return cachep->next.next == &cache_chain ?
- NULL : list_entry(cachep->next.next, struct kmem_cache, next);
+ return seq_list_next(p, &cache_chain, pos);
}
static void s_stop(struct seq_file *m, void *p)
@@ -4190,7 +4181,7 @@ static void s_stop(struct seq_file *m, v
static int s_show(struct seq_file *m, void *p)
{
- struct kmem_cache *cachep = p;
+ struct kmem_cache *cachep = list_entry(p, struct kmem_cache, next);
struct slab *slabp;
unsigned long active_objs;
unsigned long num_objs;
@@ -4359,17 +4350,8 @@ ssize_t slabinfo_write(struct file *file
static void *leaks_start(struct seq_file *m, loff_t *pos)
{
- loff_t n = *pos;
- struct list_head *p;
-
mutex_lock(&cache_chain_mutex);
- p = cache_chain.next;
- while (n--) {
- p = p->next;
- if (p == &cache_chain)
- return NULL;
- }
- return list_entry(p, struct kmem_cache, next);
+ return seq_list_start(&cache_chain, *pos);
}
static inline int add_caller(unsigned long *n, unsigned long v)
One more simple and stupid switching to the new API.
Signed-off-by: Pavel Emelianov <[email protected]>
---
diff --git a/fs/namespace.c b/fs/namespace.c
index 11f2fbf..82d4fd2 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -393,22 +393,16 @@ EXPORT_SYMBOL(mnt_unpin);
static void *m_start(struct seq_file *m, loff_t *pos)
{
struct mnt_namespace *n = m->private;
- struct list_head *p;
- loff_t l = *pos;
down_read(&namespace_sem);
- list_for_each(p, &n->list)
- if (!l--)
- return list_entry(p, struct vfsmount, mnt_list);
- return NULL;
+ return seq_list_start(&n->list, *pos);
}
static void *m_next(struct seq_file *m, void *v, loff_t *pos)
{
struct mnt_namespace *n = m->private;
- struct list_head *p = ((struct vfsmount *)v)->mnt_list.next;
- (*pos)++;
- return p == &n->list ? NULL : list_entry(p, struct vfsmount, mnt_list);
+
+ return seq_list_next(v, &n->list, pos);
}
static void m_stop(struct seq_file *m, void *v)
@@ -423,7 +417,7 @@ static inline void mangle(struct seq_fil
static int show_vfsmnt(struct seq_file *m, void *v)
{
- struct vfsmount *mnt = v;
+ struct vfsmount *mnt = list_entry(v, struct vfsmount, mnt_list);
int err = 0;
static struct proc_fs_info {
int flag;
@@ -481,7 +475,7 @@ struct seq_operations mounts_op = {
static int show_vfsstat(struct seq_file *m, void *v)
{
- struct vfsmount *mnt = v;
+ struct vfsmount *mnt = list_entry(v, struct vfsmount, mnt_list);
int err = 0;
/* device */
On Fri, May 18, 2007 at 01:34:23PM +0400, Pavel Emelianov wrote:
> Simple and stupid - just use the same code from another
> place in the kernel.
>
> Signed-off-by: Pavel Emelianov <[email protected]>
Ack.
--
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
From: Pavel Emelianov <[email protected]>
Date: Fri, 18 May 2007 13:53:13 +0400
> This includes /proc/net/protocols, /proc/net/rxrpc_calls
> and /proc/net/rxrpc_connections files.
>
> All three need seq_list_start_head to show some header.
>
> Signed-off-by: Pavel Emelianov <[email protected]>
Acked-by: David S. Miller <[email protected]>
The similar code exists here and is called capi_driver_get_idx().
Use generic helpers now and remember to convert list_head to
struct capi_driver in .show callback.
Acked-by: Karsten Keil <[email protected]>
Signed-off-by: Pavel Emelianov <[email protected]>
---
diff --git a/drivers/isdn/capi/kcapi_proc.c b/drivers/isdn/capi/kcapi_proc.c
index 31f4fd8..845a797 100644
--- a/drivers/isdn/capi/kcapi_proc.c
+++ b/drivers/isdn/capi/kcapi_proc.c
@@ -243,36 +243,15 @@ create_seq_entry(char *name, mode_t mode
// ---------------------------------------------------------------------------
-
-static __inline__ struct capi_driver *capi_driver_get_idx(loff_t pos)
-{
- struct capi_driver *drv = NULL;
- struct list_head *l;
- loff_t i;
-
- i = 0;
- list_for_each(l, &capi_drivers) {
- drv = list_entry(l, struct capi_driver, list);
- if (i++ == pos)
- return drv;
- }
- return NULL;
-}
-
static void *capi_driver_start(struct seq_file *seq, loff_t *pos)
{
- struct capi_driver *drv;
read_lock(&capi_drivers_list_lock);
- drv = capi_driver_get_idx(*pos);
- return drv;
+ return seq_list_start(&capi_drivers, *pos);
}
static void *capi_driver_next(struct seq_file *seq, void *v, loff_t *pos)
{
- struct capi_driver *drv = (struct capi_driver *)v;
- ++*pos;
- if (drv->list.next == &capi_drivers) return NULL;
- return list_entry(drv->list.next, struct capi_driver, list);
+ return seq_list_next(v, &capi_drivers, pos);
}
static void capi_driver_stop(struct seq_file *seq, void *v)
@@ -282,7 +261,8 @@ static void capi_driver_stop(struct seq_
static int capi_driver_show(struct seq_file *seq, void *v)
{
- struct capi_driver *drv = (struct capi_driver *)v;
+ struct capi_driver *drv = list_entry(v, struct capi_driver, list);
+
seq_printf(seq, "%-32s %s\n", drv->name, drv->revision);
return 0;
}
--
Karsten Keil
SuSE Labs
ISDN and VOIP development
SUSE LINUX Products GmbH, Maxfeldstr.5 90409 Nuernberg, GF: Markus Rex, HRB 16746 (AG Nuernberg)
On Fri, 2007-05-18 at 14:04 +0400, Pavel Emelianov wrote:
> This includes /proc/fs/nfsfs/servers and /proc/fs/nfsfs/volumes
> entries.
>
> Both need to show the header and use the list_head.
>
> Signed-off-by: Pavel Emelianov <[email protected]>
Acked-by: Trond Myklebust <[email protected]>
>
> ---
>
> diff --git a/fs/nfs/client.c b/fs/nfs/client.c
> index 50c6821..10355ec 100644
> --- a/fs/nfs/client.c
> +++ b/fs/nfs/client.c
> @@ -1232,23 +1232,9 @@ static int nfs_server_list_open(struct i
> */
> static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
> {
> - struct list_head *_p;
> - loff_t pos = *_pos;
> -
> /* lock the list against modification */
> spin_lock(&nfs_client_lock);
> -
> - /* allow for the header line */
> - if (!pos)
> - return SEQ_START_TOKEN;
> - pos--;
> -
> - /* find the n'th element in the list */
> - list_for_each(_p, &nfs_client_list)
> - if (!pos--)
> - break;
> -
> - return _p != &nfs_client_list ? _p : NULL;
> + return seq_list_start_head(&nfs_client_list, *_pos);
> }
>
> /*
> @@ -1256,14 +1242,7 @@ static void *nfs_server_list_start(struc
> */
> static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
> {
> - struct list_head *_p;
> -
> - (*pos)++;
> -
> - _p = v;
> - _p = (v == SEQ_START_TOKEN) ? nfs_client_list.next : _p->next;
> -
> - return _p != &nfs_client_list ? _p : NULL;
> + return seq_list_next(v, &nfs_client_list, pos);
> }
>
> /*
> @@ -1282,7 +1261,7 @@ static int nfs_server_list_show(struct s
> struct nfs_client *clp;
>
> /* display header on line 1 */
> - if (v == SEQ_START_TOKEN) {
> + if (v == &nfs_client_list) {
> seq_puts(m, "NV SERVER PORT USE HOSTNAME\n");
> return 0;
> }
> @@ -1323,23 +1302,9 @@ static int nfs_volume_list_open(struct i
> */
> static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
> {
> - struct list_head *_p;
> - loff_t pos = *_pos;
> -
> /* lock the list against modification */
> spin_lock(&nfs_client_lock);
> -
> - /* allow for the header line */
> - if (!pos)
> - return SEQ_START_TOKEN;
> - pos--;
> -
> - /* find the n'th element in the list */
> - list_for_each(_p, &nfs_volume_list)
> - if (!pos--)
> - break;
> -
> - return _p != &nfs_volume_list ? _p : NULL;
> + return seq_list_start_head(&nfs_volume_list, *_pos);
> }
>
> /*
> @@ -1347,14 +1312,7 @@ static void *nfs_volume_list_start(struc
> */
> static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
> {
> - struct list_head *_p;
> -
> - (*pos)++;
> -
> - _p = v;
> - _p = (v == SEQ_START_TOKEN) ? nfs_volume_list.next : _p->next;
> -
> - return _p != &nfs_volume_list ? _p : NULL;
> + return seq_list_next(v, &nfs_volume_list, pos);
> }
>
> /*
> @@ -1375,7 +1333,7 @@ static int nfs_volume_list_show(struct s
> char dev[8], fsid[17];
>
> /* display header on line 1 */
> - if (v == SEQ_START_TOKEN) {
> + if (v == &nfs_volume_list) {
> seq_puts(m, "NV SERVER PORT DEV FSID\n");
> return 0;
> }
>