dm-ima: more strlen() drops

Following commit ebbd17695e9e ("dm: ima: avoid extra calls to
strlen()"), convert 'dm_ima_alloc_and_copy_capacity_str()' to
return the number of characters emitted by 'scnprintf()' and
simplify the users accordingly. Compile tested only.

Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Reviewed-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>

diff --git a/drivers/md/dm-ima.c b/drivers/md/dm-ima.c
index 8b50c908c6f439663113dede71f702d9f530df61..f5c0ecc7cb0bdc06298edbd9d0408c8fad0d2218 100644 (file)
--- a/drivers/md/dm-ima.c
+++ b/drivers/md/dm-ima.c
@@ -157,10 +157,8 @@ static int dm_ima_alloc_and_copy_capacity_str(struct mapped_device *md, char **c
        if (!(*capacity_str))
                return -ENOMEM;
 
-       scnprintf(*capacity_str, DM_IMA_DEVICE_BUF_LEN, "current_device_capacity=%llu;",
-                 capacity);
-
-       return 0;
+       return scnprintf(*capacity_str, DM_IMA_DEVICE_BUF_LEN, "current_device_capacity=%llu;",
+                        capacity);
 }
 
 /*
@@ -371,18 +369,18 @@ void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap)
 {
        char *device_table_data, *dev_name = NULL, *dev_uuid = NULL, *capacity_str = NULL;
        char active[] = "active_table_hash=";
-       unsigned int active_len = strlen(active), capacity_len = 0;
+       unsigned int active_len = strlen(active);
        unsigned int l = 0;
        bool noio = true;
        bool nodata = true;
-       int r;
+       int capacity_len;
 
        device_table_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN, GFP_KERNEL, noio);
        if (!device_table_data)
                return;
 
-       r = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
-       if (r)
+       capacity_len = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
+       if (capacity_len < 0)
                goto error;
 
        memcpy(device_table_data + l, DM_IMA_VERSION_STR, md->ima.dm_version_str_len);
@@ -445,8 +443,7 @@ void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap)
        }
 
        if (nodata) {
-               r = dm_ima_alloc_and_copy_name_uuid(md, &dev_name, &dev_uuid, noio);
-               if (r)
+               if (dm_ima_alloc_and_copy_name_uuid(md, &dev_name, &dev_uuid, noio))
                        goto error;
 
                l = scnprintf(device_table_data, DM_IMA_DEVICE_BUF_LEN,
@@ -454,7 +451,6 @@ void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap)
                              DM_IMA_VERSION_STR, dev_name, dev_uuid);
        }
 
-       capacity_len = strlen(capacity_str);
        memcpy(device_table_data + l, capacity_str, capacity_len);
        l += capacity_len;
 
@@ -483,18 +479,17 @@ void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all)
        unsigned int device_active_len = strlen(device_active_str);
        unsigned int device_inactive_len = strlen(device_inactive_str);
        unsigned int remove_all_len = strlen(remove_all_str);
-       unsigned int capacity_len = 0;
        unsigned int l = 0;
        bool noio = true;
        bool nodata = true;
-       int r;
+       int capacity_len;
 
        device_table_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN*2, GFP_KERNEL, noio);
        if (!device_table_data)
                goto exit;
 
-       r = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
-       if (r) {
+       capacity_len = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
+       if (capacity_len < 0) {
                kfree(device_table_data);
                goto exit;
        }
@@ -570,7 +565,6 @@ void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all)
        memcpy(device_table_data + l, remove_all ? "y;" : "n;", 2);
        l += 2;
 
-       capacity_len = strlen(capacity_str);
        memcpy(device_table_data + l, capacity_str, capacity_len);
        l += capacity_len;
 
@@ -602,20 +596,20 @@ exit:
  */
 void dm_ima_measure_on_table_clear(struct mapped_device *md, bool new_map)
 {
-       unsigned int l = 0, capacity_len = 0;
+       unsigned int l = 0;
        char *device_table_data = NULL, *dev_name = NULL, *dev_uuid = NULL, *capacity_str = NULL;
        char inactive_str[] = "inactive_table_hash=";
        unsigned int inactive_len = strlen(inactive_str);
        bool noio = true;
        bool nodata = true;
-       int r;
+       int capacity_len;
 
        device_table_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN, GFP_KERNEL, noio);
        if (!device_table_data)
                return;
 
-       r = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
-       if (r)
+       capacity_len = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
+       if (capacity_len < 0)
                goto error1;
 
        memcpy(device_table_data + l, DM_IMA_VERSION_STR, md->ima.dm_version_str_len);
@@ -650,7 +644,6 @@ void dm_ima_measure_on_table_clear(struct mapped_device *md, bool new_map)
                              DM_IMA_VERSION_STR, dev_name, dev_uuid);
        }
 
-       capacity_len = strlen(capacity_str);
        memcpy(device_table_data + l, capacity_str, capacity_len);
        l += capacity_len;
 
@@ -703,7 +696,7 @@ void dm_ima_measure_on_device_rename(struct mapped_device *md)
        char *old_device_data = NULL, *new_device_data = NULL, *combined_device_data = NULL;
        char *new_dev_name = NULL, *new_dev_uuid = NULL, *capacity_str = NULL;
        bool noio = true;
-       int r, len;
+       int len;
 
        if (dm_ima_alloc_and_copy_device_data(md, &new_device_data,
                                              md->ima.active_table.num_targets, noio))
@@ -716,8 +709,7 @@ void dm_ima_measure_on_device_rename(struct mapped_device *md)
        if (!combined_device_data)
                goto error;
 
-       r = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
-       if (r)
+       if (dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio) < 0)
                goto error;
 
        old_device_data = md->ima.active_table.device_metadata;