[PATCH] regulator: core: Fix size limit of supply_map

From: Haishan Zhou
Date: Thu Jun 29 2017 - 23:43:42 EST


Now the debugfs file supply_map has a size limit PAGE_SIZE and the user
can not see the whole content of regulator_map_list when it is larger
than this limit.

This patch uses seq_file instead to make sure supply_map shows the full
information of regulator_map_list.

Signed-off-by: Haishan Zhou <zhssmail@xxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
drivers/regulator/core.c | 36 +++++++++++++-----------------------
1 file changed, 13 insertions(+), 23 deletions(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index a0362a63902e..f8e76f73da35 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -4311,41 +4311,31 @@ void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);

#ifdef CONFIG_DEBUG_FS
-static ssize_t supply_map_read_file(struct file *file, char __user *user_buf,
- size_t count, loff_t *ppos)
+static int supply_map_show(struct seq_file *sf, void *data)
{
- char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
- ssize_t len, ret = 0;
struct regulator_map *map;

- if (!buf)
- return -ENOMEM;
-
list_for_each_entry(map, &regulator_map_list, list) {
- len = snprintf(buf + ret, PAGE_SIZE - ret,
- "%s -> %s.%s\n",
- rdev_get_name(map->regulator), map->dev_name,
- map->supply);
- if (len >= 0)
- ret += len;
- if (ret > PAGE_SIZE) {
- ret = PAGE_SIZE;
- break;
- }
+ seq_printf(sf, "%s -> %s.%s\n",
+ rdev_get_name(map->regulator), map->dev_name,
+ map->supply);
}

- ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
-
- kfree(buf);
+ return 0;
+}

- return ret;
+static int supply_map_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, supply_map_show, inode->i_private);
}
#endif

static const struct file_operations supply_map_fops = {
#ifdef CONFIG_DEBUG_FS
- .read = supply_map_read_file,
- .llseek = default_llseek,
+ .open = supply_map_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
#endif
};

--
2.13.2