floppy: add FD_AUTODETECT_SIZE define for struct floppy_drive_params

Use FD_AUTODETECT_SIZE for autodetect buffer size in struct
floppy_drive_params instead of a magic number.

Link: https://lore.kernel.org/r/20200501134416.72248-3-efremov@linux.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Denis Efremov <efremov@linux.com>

diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
index 3ab6e80..b82b3d3 100644 (file)
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -2073,7 +2073,8 @@ static int next_valid_format(int drive)
 
        probed_format = drive_state[drive].probed_format;
        while (1) {
-               if (probed_format >= 8 || !drive_params[drive].autodetect[probed_format]) {
+               if (probed_format >= FD_AUTODETECT_SIZE ||
+                   !drive_params[drive].autodetect[probed_format]) {
                        drive_state[drive].probed_format = 0;
                        return 1;
                }
@@ -3442,13 +3443,13 @@ static int fd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
        return 0;
 }
 
-static bool valid_floppy_drive_params(const short autodetect[8],
+static bool valid_floppy_drive_params(const short autodetect[FD_AUTODETECT_SIZE],
                int native_format)
 {
        size_t floppy_type_size = ARRAY_SIZE(floppy_type);
        size_t i = 0;
 
-       for (i = 0; i < 8; ++i) {
+       for (i = 0; i < FD_AUTODETECT_SIZE; ++i) {
                if (autodetect[i] < 0 ||
                    autodetect[i] >= floppy_type_size)
                        return false;
@@ -3673,7 +3674,7 @@ struct compat_floppy_drive_params {
        struct floppy_max_errors max_errors;
        char            flags;
        char            read_track;
-       short           autodetect[8];
+       short           autodetect[FD_AUTODETECT_SIZE];
        compat_int_t    checkfreq;
        compat_int_t    native_format;
 };

diff --git a/include/uapi/linux/fd.h b/include/uapi/linux/fd.h
index 90fb947..3f6b7be 100644 (file)
--- a/include/uapi/linux/fd.h
+++ b/include/uapi/linux/fd.h
@@ -172,7 +172,10 @@ struct floppy_drive_params {
  * used in succession to try to read the disk. If the FDC cannot lock onto
  * the disk, the next format is tried. This uses the variable 'probing'.
  */
-       short autodetect[8];            /* autodetected formats */
+
+#define FD_AUTODETECT_SIZE 8
+
+       short autodetect[FD_AUTODETECT_SIZE]; /* autodetected formats */
        
        int checkfreq; /* how often should the drive be checked for disk 
                        * changes */