target: writev() on single-element vector is pointless

... in other news:
	filp_open() can't return a struct file with NULL dentry
	filp_open() can't return a struct file negative dentry
	filp_close() of something that never had been in any descriptor
tables is pointless - fput() is all you need

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2 files changed, 17 insertions, 45 deletions

diff --git a/drivers/target/target_core_alua.c b/drivers/target/target_core_alua.c
index 7d4ec02e29a9..ff1c5ee352cb 100644
--- a/drivers/target/target_core_alua.c
+++ b/drivers/target/target_core_alua.c
@@ -27,6 +27,7 @@
 #include <linux/spinlock.h>
 #include <linux/configfs.h>
 #include <linux/export.h>
+#include <linux/file.h>
 #include <scsi/scsi.h>
 #include <scsi/scsi_cmnd.h>
 #include <asm/unaligned.h>
@@ -715,36 +716,18 @@ static int core_alua_write_tpg_metadata(
         unsigned char *md_buf,
         u32 md_buf_len)
 {
-        mm_segment_t old_fs;
-        struct file *file;
-        struct iovec iov[1];
-        int flags = O_RDWR | O_CREAT | O_TRUNC, ret;
-
-        memset(iov, 0, sizeof(struct iovec));
+        struct file *file = filp_open(path, O_RDWR | O_CREAT | O_TRUNC, 0600);
+        int ret;
 
-        file = filp_open(path, flags, 0600);
-        if (IS_ERR(file) || !file || !file->f_dentry) {
-                pr_err("filp_open(%s) for ALUA metadata failed\n",
-                        path);
+        if (IS_ERR(file)) {
+                pr_err("filp_open(%s) for ALUA metadata failed\n", path);
                 return -ENODEV;
         }
-
-        iov[0].iov_base = &md_buf[0];
-        iov[0].iov_len = md_buf_len;
-
-        old_fs = get_fs();
-        set_fs(get_ds());
-        ret = vfs_writev(file, &iov[0], 1, &file->f_pos);
-        set_fs(old_fs);
-
-        if (ret < 0) {
+        ret = kernel_write(file, md_buf, md_buf_len, 0);
+        if (ret < 0)
                 pr_err("Error writing ALUA metadata file: %s\n", path);
-                filp_close(file, NULL);
-                return -EIO;
-        }
-        filp_close(file, NULL);
-
-        return 0;
+        fput(file);
+        return ret ? -EIO : 0;
 }
 
 /*
diff --git a/drivers/target/target_core_pr.c b/drivers/target/target_core_pr.c
index 8e0290b38e43..3240f2cc81ef 100644
--- a/drivers/target/target_core_pr.c
+++ b/drivers/target/target_core_pr.c
@@ -27,6 +27,7 @@
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/list.h>
+#include <linux/file.h>
 #include <scsi/scsi.h>
 #include <scsi/scsi_cmnd.h>
 #include <asm/unaligned.h>
@@ -1957,13 +1958,10 @@ static int __core_scsi3_write_aptpl_to_file(
 {
         struct t10_wwn *wwn = &dev->t10_wwn;
         struct file *file;
-        struct iovec iov[1];
-        mm_segment_t old_fs;
         int flags = O_RDWR | O_CREAT | O_TRUNC;
         char path[512];
         int ret;
 
-        memset(iov, 0, sizeof(struct iovec));
         memset(path, 0, 512);
 
         if (strlen(&wwn->unit_serial[0]) >= 512) {
@@ -1974,31 +1972,22 @@ static int __core_scsi3_write_aptpl_to_file(
 
         snprintf(path, 512, "/var/target/pr/aptpl_%s", &wwn->unit_serial[0]);
         file = filp_open(path, flags, 0600);
-        if (IS_ERR(file) || !file || !file->f_dentry) {
+        if (IS_ERR(file)) {
                 pr_err("filp_open(%s) for APTPL metadata"
                         " failed\n", path);
-                return IS_ERR(file) ? PTR_ERR(file) : -ENOENT;
+                return PTR_ERR(file);
         }
 
-        iov[0].iov_base = &buf[0];
         if (!pr_aptpl_buf_len)
-                iov[0].iov_len = (strlen(&buf[0]) + 1); /* Add extra for NULL */
-        else
-                iov[0].iov_len = pr_aptpl_buf_len;
+                pr_aptpl_buf_len = (strlen(&buf[0]) + 1); /* Add extra for NULL */
 
-        old_fs = get_fs();
-        set_fs(get_ds());
-        ret = vfs_writev(file, &iov[0], 1, &file->f_pos);
-        set_fs(old_fs);
+        ret = kernel_write(file, buf, pr_aptpl_buf_len, 0);
 
-        if (ret < 0) {
+        if (ret < 0)
                 pr_debug("Error writing APTPL metadata file: %s\n", path);
-                filp_close(file, NULL);
-                return -EIO;
-        }
-        filp_close(file, NULL);
+        fput(file);
 
-        return 0;
+        return ret ? -EIO : 0;
 }
 
 static int