[PATCH 16/39] ipmi: simplify procfs code

Christoph Hellwig
2018-04-19T12:41:17Z

Use remove_proc_subtree to remove the whole subtree on cleanup instead
of a hand rolled list of proc entries, unwind the registration loop into
individual calls. Switch to use proc_create_single to further simplify
the code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/char/ipmi/ipmi_msghandler.c | 150 +++++-----------------------
drivers/char/ipmi/ipmi_si_intf.c | 47 +--------
drivers/char/ipmi/ipmi_ssif.c | 34 +------
include/linux/ipmi_smi.h | 8 +-
4 files changed, 33 insertions(+), 206 deletions(-)

diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c
index 361148938801..c18db313e4c4 100644
--- a/drivers/char/ipmi/ipmi_msghandler.c
+++ b/drivers/char/ipmi/ipmi_msghandler.c
@@ -247,13 +247,6 @@ struct ipmi_my_addrinfo {
unsigned char lun;
};

-#ifdef CONFIG_IPMI_PROC_INTERFACE
-struct ipmi_proc_entry {
- char *name;
- struct ipmi_proc_entry *next;
-};
-#endif
-
/*
* Note that the product id, manufacturer id, guid, and device id are
* immutable in this structure, so dyn_mutex is not required for
@@ -430,10 +423,6 @@ struct ipmi_smi {
void *send_info;

#ifdef CONFIG_IPMI_PROC_INTERFACE
- /* A list of proc entries for this interface. */
- struct mutex proc_entry_lock;
- struct ipmi_proc_entry *proc_entries;
-
struct proc_dir_entry *proc_dir;
char proc_dir_name[10];
#endif
@@ -2358,18 +2347,6 @@ static int smi_ipmb_proc_show(struct seq_file *m, void *v)
return 0;
}

-static int smi_ipmb_proc_open(struct inode *inode, struct file *file)
-{
- return single_open(file, smi_ipmb_proc_show, PDE_DATA(inode));
-}
-
-static const struct file_operations smi_ipmb_proc_ops = {
- .open = smi_ipmb_proc_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
-
static int smi_version_proc_show(struct seq_file *m, void *v)
{
ipmi_smi_t intf = m->private;
@@ -2387,18 +2364,6 @@ static int smi_version_proc_show(struct seq_file *m, void *v)
return 0;
}

-static int smi_version_proc_open(struct inode *inode, struct file *file)
-{
- return single_open(file, smi_version_proc_show, PDE_DATA(inode));
-}
-
-static const struct file_operations smi_version_proc_ops = {
- .open = smi_version_proc_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
-
static int smi_stats_proc_show(struct seq_file *m, void *v)
{
ipmi_smi_t intf = m->private;
@@ -2462,95 +2427,45 @@ static int smi_stats_proc_show(struct seq_file *m, void *v)
return 0;
}

-static int smi_stats_proc_open(struct inode *inode, struct file *file)
-{
- return single_open(file, smi_stats_proc_show, PDE_DATA(inode));
-}
-
-static const struct file_operations smi_stats_proc_ops = {
- .open = smi_stats_proc_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
-
int ipmi_smi_add_proc_entry(ipmi_smi_t smi, char *name,
- const struct file_operations *proc_ops,
- void *data)
+ int (*show)(struct seq_file *, void *), void *data)
{
- int rv = 0;
- struct proc_dir_entry *file;
- struct ipmi_proc_entry *entry;
-
- /* Create a list element. */
- entry = kmalloc(sizeof(*entry), GFP_KERNEL);
- if (!entry)
+ if (!proc_create_single_data(name, 0, smi->proc_dir, show, data))
return -ENOMEM;
- entry->name = kstrdup(name, GFP_KERNEL);
- if (!entry->name) {
- kfree(entry);
- return -ENOMEM;
- }
-
- file = proc_create_data(name, 0, smi->proc_dir, proc_ops, data);
- if (!file) {
- kfree(entry->name);
- kfree(entry);
- rv = -ENOMEM;
- } else {
- mutex_lock(&smi->proc_entry_lock);
- /* Stick it on the list. */
- entry->next = smi->proc_entries;
- smi->proc_entries = entry;
- mutex_unlock(&smi->proc_entry_lock);
- }
-
- return rv;
+ return 0;
}
EXPORT_SYMBOL(ipmi_smi_add_proc_entry);

static int add_proc_entries(ipmi_smi_t smi, int num)
{
- int rv = 0;
-
sprintf(smi->proc_dir_name, "%d", num);
smi->proc_dir = proc_mkdir(smi->proc_dir_name, proc_ipmi_root);
if (!smi->proc_dir)
- rv = -ENOMEM;
-
- if (rv == 0)
- rv = ipmi_smi_add_proc_entry(smi, "stats",
- &smi_stats_proc_ops,
- smi);
-
- if (rv == 0)
- rv = ipmi_smi_add_proc_entry(smi, "ipmb",
- &smi_ipmb_proc_ops,
- smi);
-
- if (rv == 0)
- rv = ipmi_smi_add_proc_entry(smi, "version",
- &smi_version_proc_ops,
- smi);
-
- return rv;
+ return -ENOMEM;
+ if (!proc_create_single_data("stats", 0, smi->proc_dir,
+ smi_stats_proc_show, smi))
+ return -ENOMEM;
+ if (!proc_create_single_data("ipmb", 0, smi->proc_dir,
+ smi_ipmb_proc_show, smi))
+ return -ENOMEM;
+ if (!proc_create_single_data("version", 0, smi->proc_dir,
+ smi_version_proc_show, smi))
+ return -ENOMEM;
+ return 0;
}

static void remove_proc_entries(ipmi_smi_t smi)
{
- struct ipmi_proc_entry *entry;
-
- mutex_lock(&smi->proc_entry_lock);
- while (smi->proc_entries) {
- entry = smi->proc_entries;
- smi->proc_entries = entry->next;
-
- remove_proc_entry(entry->name, smi->proc_dir);
- kfree(entry->name);
- kfree(entry);
- }
- mutex_unlock(&smi->proc_entry_lock);
- remove_proc_entry(smi->proc_dir_name, proc_ipmi_root);
+ if (smi->proc_dir)
+ remove_proc_subtree(smi->proc_dir_name, proc_ipmi_root);
+}
+#else
+static int add_proc_entries(ipmi_smi_t smi, int num)
+{
+ return 0;
+}
+static void remove_proc_entries(ipmi_smi_t smi)
+{
}
#endif /* CONFIG_IPMI_PROC_INTERFACE */

@@ -3386,9 +3301,6 @@ int ipmi_register_smi(const struct ipmi_smi_handlers *handlers,
intf->seq_table[j].seqid = 0;
}
intf->curr_seq = 0;
-#ifdef CONFIG_IPMI_PROC_INTERFACE
- mutex_init(&intf->proc_entry_lock);
-#endif
spin_lock_init(&intf->waiting_rcv_msgs_lock);
INIT_LIST_HEAD(&intf->waiting_rcv_msgs);
tasklet_init(&intf->recv_tasklet,
@@ -3410,10 +3322,6 @@ int ipmi_register_smi(const struct ipmi_smi_handlers *handlers,
for (i = 0; i < IPMI_NUM_STATS; i++)
atomic_set(&intf->stats[i], 0);

-#ifdef CONFIG_IPMI_PROC_INTERFACE
- intf->proc_dir = NULL;
-#endif
-
mutex_lock(&smi_watchers_mutex);
mutex_lock(&ipmi_interfaces_mutex);
/* Look for a hole in the numbers. */
@@ -3448,17 +3356,11 @@ int ipmi_register_smi(const struct ipmi_smi_handlers *handlers,
if (rv)
goto out;

-#ifdef CONFIG_IPMI_PROC_INTERFACE
rv = add_proc_entries(intf, i);
-#endif
-
out:
if (rv) {
ipmi_bmc_unregister(intf);
-#ifdef CONFIG_IPMI_PROC_INTERFACE
- if (intf->proc_dir)
- remove_proc_entries(intf);
-#endif
+ remove_proc_entries(intf);
intf->handlers = NULL;
list_del_rcu(&intf->link);
mutex_unlock(&ipmi_interfaces_mutex);
@@ -3563,9 +3465,7 @@ int ipmi_unregister_smi(ipmi_smi_t intf)
intf->handlers = NULL;
mutex_unlock(&ipmi_interfaces_mutex);

-#ifdef CONFIG_IPMI_PROC_INTERFACE
remove_proc_entries(intf);
-#endif
ipmi_bmc_unregister(intf);

/*
diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c
index ff870aa91cfe..7acc8cbf8d6f 100644
--- a/drivers/char/ipmi/ipmi_si_intf.c
+++ b/drivers/char/ipmi/ipmi_si_intf.c
@@ -1602,18 +1602,6 @@ static int smi_type_proc_show(struct seq_file *m, void *v)
return 0;
}

-static int smi_type_proc_open(struct inode *inode, struct file *file)
-{
- return single_open(file, smi_type_proc_show, PDE_DATA(inode));
-}
-
-static const struct file_operations smi_type_proc_ops = {
- .open = smi_type_proc_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
-
static int smi_si_stats_proc_show(struct seq_file *m, void *v)
{
struct smi_info *smi = m->private;
@@ -1645,18 +1633,6 @@ static int smi_si_stats_proc_show(struct seq_file *m, void *v)
return 0;
}

-static int smi_si_stats_proc_open(struct inode *inode, struct file *file)
-{
- return single_open(file, smi_si_stats_proc_show, PDE_DATA(inode));
-}
-
-static const struct file_operations smi_si_stats_proc_ops = {
- .open = smi_si_stats_proc_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
-
static int smi_params_proc_show(struct seq_file *m, void *v)
{
struct smi_info *smi = m->private;
@@ -1674,18 +1650,6 @@ static int smi_params_proc_show(struct seq_file *m, void *v)

return 0;
}
-
-static int smi_params_proc_open(struct inode *inode, struct file *file)
-{
- return single_open(file, smi_params_proc_show, PDE_DATA(inode));
-}
-
-static const struct file_operations smi_params_proc_ops = {
- .open = smi_params_proc_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
#endif

#define IPMI_SI_ATTR(name) \
@@ -2182,10 +2146,8 @@ static int try_smi_init(struct smi_info *new_smi)
goto out_err;
}

-#ifdef CONFIG_IPMI_PROC_INTERFACE
rv = ipmi_smi_add_proc_entry(new_smi->intf, "type",
- &smi_type_proc_ops,
- new_smi);
+ smi_type_proc_show, new_smi);
if (rv) {
dev_err(new_smi->io.dev,
"Unable to create proc entry: %d\n", rv);
@@ -2193,8 +2155,7 @@ static int try_smi_init(struct smi_info *new_smi)
}

rv = ipmi_smi_add_proc_entry(new_smi->intf, "si_stats",
- &smi_si_stats_proc_ops,
- new_smi);
+ smi_si_stats_proc_show, new_smi);
if (rv) {
dev_err(new_smi->io.dev,
"Unable to create proc entry: %d\n", rv);
@@ -2202,14 +2163,12 @@ static int try_smi_init(struct smi_info *new_smi)
}

rv = ipmi_smi_add_proc_entry(new_smi->intf, "params",
- &smi_params_proc_ops,
- new_smi);
+ smi_params_proc_show, new_smi);
if (rv) {
dev_err(new_smi->io.dev,
"Unable to create proc entry: %d\n", rv);
goto out_err;
}
-#endif

/* Don't increment till we know we have succeeded. */
smi_num++;
diff --git a/drivers/char/ipmi/ipmi_ssif.c b/drivers/char/ipmi/ipmi_ssif.c
index 35a82f4bfd78..57f6116a17b2 100644
--- a/drivers/char/ipmi/ipmi_ssif.c
+++ b/drivers/char/ipmi/ipmi_ssif.c
@@ -1349,18 +1349,6 @@ static int smi_type_proc_show(struct seq_file *m, void *v)
return 0;
}

-static int smi_type_proc_open(struct inode *inode, struct file *file)
-{
- return single_open(file, smi_type_proc_show, inode->i_private);
-}
-
-static const struct file_operations smi_type_proc_ops = {
- .open = smi_type_proc_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
-
static int smi_stats_proc_show(struct seq_file *m, void *v)
{
struct ssif_info *ssif_info = m->private;
@@ -1393,18 +1381,6 @@ static int smi_stats_proc_show(struct seq_file *m, void *v)
ssif_get_stat(ssif_info, alerts));
return 0;
}
-
-static int smi_stats_proc_open(struct inode *inode, struct file *file)
-{
- return single_open(file, smi_stats_proc_show, PDE_DATA(inode));
-}
-
-static const struct file_operations smi_stats_proc_ops = {
- .open = smi_stats_proc_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
#endif

static int strcmp_nospace(char *s1, char *s2)
@@ -1740,23 +1716,19 @@ static int ssif_probe(struct i2c_client *client, const struct i2c_device_id *id)
goto out_remove_attr;
}

-#ifdef CONFIG_IPMI_PROC_INTERFACE
rv = ipmi_smi_add_proc_entry(ssif_info->intf, "type",
- &smi_type_proc_ops,
- ssif_info);
+ smi_type_proc_show, ssif_info);
if (rv) {
pr_err(PFX "Unable to create proc entry: %d\n", rv);
goto out_err_unreg;
}

rv = ipmi_smi_add_proc_entry(ssif_info->intf, "ssif_stats",
- &smi_stats_proc_ops,
- ssif_info);
+ smi_stats_proc_show, ssif_info);
if (rv) {
pr_err(PFX "Unable to create proc entry: %d\n", rv);
goto out_err_unreg;
}
-#endif

out:
if (rv) {
@@ -1775,10 +1747,8 @@ static int ssif_probe(struct i2c_client *client, const struct i2c_device_id *id)
kfree(resp);
return rv;

-#ifdef CONFIG_IPMI_PROC_INTERFACE
out_err_unreg:
ipmi_unregister_smi(ssif_info->intf);
-#endif

out_remove_attr:
device_remove_group(&ssif_info->client->dev, &ipmi_ssif_dev_attr_group);
diff --git a/include/linux/ipmi_smi.h b/include/linux/ipmi_smi.h
index af457b5a689e..78d9fd480fe8 100644
--- a/include/linux/ipmi_smi.h
+++ b/include/linux/ipmi_smi.h
@@ -223,12 +223,10 @@ static inline void ipmi_free_smi_msg(struct ipmi_smi_msg *msg)
}

#ifdef CONFIG_IPMI_PROC_INTERFACE
-/* Allow the lower layer to add things to the proc filesystem
- directory for this interface. Note that the entry will
- automatically be dstroyed when the interface is destroyed. */
int ipmi_smi_add_proc_entry(ipmi_smi_t smi, char *name,
- const struct file_operations *proc_ops,
- void *data);
+ int (*show)(struct seq_file *, void *), void *data);
+#else
+#define ipmi_smi_add_proc_entry(smi, name, show, data) 0
#endif

#endif /* __LINUX_IPMI_SMI_H */
--
2.17.0

------------------------------------------------------------------------------
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