cx25821: sanitize cx25821_openfile_audio() a bit...

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

1 files changed, 28 insertions, 68 deletions

diff --git a/drivers/media/pci/cx25821/cx25821-audio-upstream.c b/drivers/media/pci/cx25821/cx25821-audio-upstream.c
index d930f308e94e..d6dfb5765d0b 100644
--- a/drivers/media/pci/cx25821/cx25821-audio-upstream.c
+++ b/drivers/media/pci/cx25821/cx25821-audio-upstream.c
@@ -321,81 +321,41 @@ static void cx25821_audioups_handler(struct work_struct *work)
 static int cx25821_openfile_audio(struct cx25821_dev *dev,
                            struct sram_channel *sram_ch)
 {
-        struct file *myfile;
-        int i = 0, j = 0;
-        int line_size = AUDIO_LINE_SIZE;
-        ssize_t vfs_read_retval = 0;
-        char mybuf[line_size];
-        loff_t pos;
-        loff_t offset = (unsigned long)0;
-        mm_segment_t old_fs;
-
-        myfile = filp_open(dev->_audiofilename, O_RDONLY | O_LARGEFILE, 0);
-
-        if (IS_ERR(myfile)) {
-                const int open_errno = -PTR_ERR(myfile);
-                pr_err("%s(): ERROR opening file(%s) with errno = %d!\n",
-                        __func__, dev->_audiofilename, open_errno);
-                return PTR_ERR(myfile);
-        } else {
-                if (!(myfile->f_op)) {
-                        pr_err("%s(): File has no file operations registered!\n",
-                                __func__);
-                        filp_close(myfile, NULL);
-                        return -EIO;
-                }
-
-                if (!myfile->f_op->read) {
-                        pr_err("%s(): File has no READ operations registered!\n",
-                                __func__);
-                        filp_close(myfile, NULL);
-                        return -EIO;
-                }
-
-                pos = myfile->f_pos;
-                old_fs = get_fs();
-                set_fs(KERNEL_DS);
-
-                for (j = 0; j < NUM_AUDIO_FRAMES; j++) {
-                        for (i = 0; i < dev->_audio_lines_count; i++) {
-                                pos = offset;
-
-                                vfs_read_retval = vfs_read(myfile, mybuf,
-                                                line_size, &pos);
-
-                                if (vfs_read_retval > 0 &&
-                                    vfs_read_retval == line_size &&
-                                    dev->_audiodata_buf_virt_addr != NULL) {
-                                        memcpy((void *)(dev->
-                                                        _audiodata_buf_virt_addr
-                                                        + offset / 4), mybuf,
-                                               vfs_read_retval);
-                                }
+        char *p = (void *)dev->_audiodata_buf_virt_addr;
+        struct file *file;
+        loff_t offset;
+        int i, j;
 
-                                offset += vfs_read_retval;
+        file = filp_open(dev->_audiofilename, O_RDONLY | O_LARGEFILE, 0);
+        if (IS_ERR(file)) {
+                pr_err("%s(): ERROR opening file(%s) with errno = %ld!\n",
+                        __func__, dev->_audiofilename, PTR_ERR(file));
+                return PTR_ERR(file);
+        }
 
-                                if (vfs_read_retval < line_size) {
-                                        pr_info("Done: exit %s() since no more bytes to read from Audio file\n",
-                                                __func__);
-                                        break;
-                                }
+        for (j = 0, offset = 0; j < NUM_AUDIO_FRAMES; j++) {
+                for (i = 0; i < dev->_audio_lines_count; i++) {
+                        char buf[AUDIO_LINE_SIZE];
+                        int n = kernel_read(file, offset, buf,
+                                                AUDIO_LINE_SIZE);
+
+                        if (n < AUDIO_LINE_SIZE) {
+                                pr_info("Done: exit %s() since no more bytes to read from Audio file\n",
+                                        __func__);
+                                dev->_audiofile_status = END_OF_FILE;
+                                fput(file);
+                                return 0;
                         }
 
-                        if (i > 0)
-                                dev->_audioframe_count++;
+                        if (p)
+                                memcpy(p + offset, buf, n);
 
-                        if (vfs_read_retval < line_size)
-                                break;
+                        offset += n;
                 }
-
-                dev->_audiofile_status = (vfs_read_retval == line_size) ?
-                                                IN_PROGRESS : END_OF_FILE;
-
-                set_fs(old_fs);
-                myfile->f_pos = 0;
-                filp_close(myfile, NULL);
+                dev->_audioframe_count++;
         }
-
+        dev->_audiofile_status = IN_PROGRESS;
+        fput(file);
         return 0;
 }