To provide a real world example of how allowing struct gendisk
to be initialized from pointer, here is a port of drivers/ide to use
init_disk() instead of alloc_disk(), making the code 16 lines shorter
(well, two lines were from deleting unnecessary "drive->disk = NULL;"
statements, so 14 lines). I am running the resulting code now.
I am not submitting these IDE changes yet. I wanted to
illustrate the clean-ups enabled by being able to initialize a struct
gendisk from a pointer.
--
Adam J. Richter __ ______________ 575 Oroville Road
adam@yggdrasil.com \ / Milpitas, California 95035
+1 408 309-6081 | g g d r a s i l United States of America
"Free Software For The Rest Of Us."
--vtzGhvizbBRQ85DL
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment; filename=diffs
diff -u -r linux/drivers/ide.bak/ide-cd.c linux/drivers/ide/ide-cd.c
--- linux/drivers/ide.bak/ide-cd.c 2002-11-04 21:38:05.000000000 -0800
+++ linux/drivers/ide/ide-cd.c 2002-11-06 05:44:22.000000000 -0800
@@ -2337,7 +2337,7 @@
if (stat)
toc->capacity = 0x1fffff;
- set_capacity(drive->disk, toc->capacity * SECTORS_PER_FRAME);
+ set_capacity(&drive->disk, toc->capacity * SECTORS_PER_FRAME);
/* Remember that we've read this stuff. */
CDROM_STATE_FLAGS(drive)->toc_valid = 1;
@@ -3071,7 +3071,7 @@
/*
* default to read-only always and fix latter at the bottom
*/
- set_disk_ro(drive->disk, 1);
+ set_disk_ro(&drive->disk, 1);
blk_queue_hardsect_size(&drive->queue, CD_FRAMESIZE);
blk_queue_prep_rq(&drive->queue, ide_cdrom_prep_fn);
@@ -3194,7 +3194,7 @@
nslots = ide_cdrom_probe_capabilities (drive);
if (CDROM_CONFIG_FLAGS(drive)->dvd_ram)
- set_disk_ro(drive->disk, 0);
+ set_disk_ro(&drive->disk, 0);
#if 0
drive->dsc_overlap = (HWIF(drive)->no_dsc) ? 0 : 1;
@@ -3230,7 +3230,7 @@
{
struct cdrom_info *info = drive->driver_data;
struct cdrom_device_info *devinfo = &info->devinfo;
- struct gendisk *g = drive->disk;
+ struct gendisk *g = &drive->disk;
if (ide_unregister_subdriver(drive)) {
printk("%s: %s: failed to ide_unregister_subdriver\n",
@@ -3345,7 +3345,7 @@
static int ide_cdrom_attach (ide_drive_t *drive)
{
struct cdrom_info *info;
- struct gendisk *g = drive->disk;
+ struct gendisk *g = &drive->disk;
struct request_sense sense;
if (!strstr("ide-cdrom", drive->driver_req))
diff -u -r linux/drivers/ide.bak/ide-disk.c linux/drivers/ide/ide-disk.c
--- linux/drivers/ide.bak/ide-disk.c 2002-10-29 20:26:53.000000000 -0800
+++ linux/drivers/ide/ide-disk.c 2002-11-06 05:44:02.000000000 -0800
@@ -1669,7 +1669,7 @@
static int idedisk_cleanup (ide_drive_t *drive)
{
- struct gendisk *g = drive->disk;
+ struct gendisk *g = &drive->disk;
if ((drive->id->cfs_enable_2 & 0x3000) && drive->wcache)
if (do_idedisk_flushcache(drive))
@@ -1786,7 +1786,7 @@
static int idedisk_attach(ide_drive_t *drive)
{
- struct gendisk *g = drive->disk;
+ struct gendisk *g = &drive->disk;
/* strstr("foo", "") is non-NULL */
if (!strstr("ide-disk", drive->driver_req))
diff -u -r linux/drivers/ide.bak/ide-floppy.c linux/drivers/ide/ide-floppy.c
--- linux/drivers/ide.bak/ide-floppy.c 2002-11-04 21:38:06.000000000 -0800
+++ linux/drivers/ide/ide-floppy.c 2002-11-06 05:43:41.000000000 -0800
@@ -1412,7 +1412,7 @@
drive->bios_cyl = 0;
drive->bios_head = drive->bios_sect = 0;
floppy->blocks = floppy->bs_factor = 0;
- set_capacity(drive->disk, 0);
+ set_capacity(&drive->disk, 0);
idefloppy_create_read_capacity_cmd(&pc);
if (idefloppy_queue_pc_tail(drive, &pc)) {
@@ -1486,7 +1486,7 @@
(void) idefloppy_get_flexible_disk_page(drive);
}
- set_capacity(drive->disk, floppy->blocks * floppy->bs_factor);
+ set_capacity(&drive->disk, floppy->blocks * floppy->bs_factor);
return rc;
}
@@ -1851,7 +1851,7 @@
static int idefloppy_cleanup (ide_drive_t *drive)
{
idefloppy_floppy_t *floppy = drive->driver_data;
- struct gendisk *g = drive->disk;
+ struct gendisk *g = &drive->disk;
if (ide_unregister_subdriver(drive))
return 1;
@@ -2069,7 +2069,7 @@
static int idefloppy_attach (ide_drive_t *drive)
{
idefloppy_floppy_t *floppy;
- struct gendisk *g = drive->disk;
+ struct gendisk *g = &drive->disk;
if (!strstr("ide-floppy", drive->driver_req))
goto failed;
if (!drive->present)
diff -u -r linux/drivers/ide.bak/ide-geometry.c linux/drivers/ide/ide-geometry.c
--- linux/drivers/ide.bak/ide-geometry.c 2002-10-19 20:13:10.000000000 -0700
+++ linux/drivers/ide/ide-geometry.c 2002-11-06 05:43:01.000000000 -0800
@@ -203,7 +203,7 @@
ret = 1;
}
- set_capacity(drive->disk, current_capacity(drive));
+ set_capacity(&drive->disk, current_capacity(drive));
if (ret)
printk(KERN_INFO "%s%s [%d/%d/%d]", msg, msg1,
diff -u -r linux/drivers/ide.bak/ide-probe.c linux/drivers/ide/ide-probe.c
--- linux/drivers/ide.bak/ide-probe.c 2002-10-29 20:34:53.000000000 -0800
+++ linux/drivers/ide/ide-probe.c 2002-11-06 05:46:31.000000000 -0800
@@ -1002,36 +1002,25 @@
if (!drive->driver)
return NULL;
*part &= (1 << PARTN_BITS) - 1;
- return get_disk(drive->disk);
+ return get_disk(&drive->disk);
}
-static int alloc_disks(ide_hwif_t *hwif)
+static void alloc_disks(ide_hwif_t *hwif)
{
unsigned int unit;
- struct gendisk *disks[MAX_DRIVES];
- for (unit = 0; unit < MAX_DRIVES; unit++) {
- disks[unit] = alloc_disk(1 << PARTN_BITS);
- if (!disks[unit])
- goto Enomem;
- }
for (unit = 0; unit < MAX_DRIVES; ++unit) {
ide_drive_t *drive = &hwif->drives[unit];
- struct gendisk *disk = disks[unit];
+ struct gendisk *disk = &drive->disk;
+ init_disk(disk, 1 << PARTN_BITS);
+ disk->part = drive->disk_partitions;
disk->major = hwif->major;
disk->first_minor = unit << PARTN_BITS;
sprintf(disk->disk_name,"hd%c",'a'+hwif->index*MAX_DRIVES+unit);
disk->fops = ide_fops;
disk->private_data = drive;
disk->queue = &drive->queue;
- drive->disk = disk;
}
- return 0;
-Enomem:
- printk(KERN_WARNING "(ide::init_gendisk) Out of memory\n");
- while (unit--)
- put_disk(disks[unit]);
- return -ENOMEM;
}
/*
@@ -1101,9 +1090,8 @@
return 0;
}
- if (alloc_disks(hwif) < 0)
- goto out;
-
+ alloc_disks(hwif);
+
if (init_irq(hwif) == 0)
goto done;
@@ -1132,11 +1120,9 @@
out_disks:
for (unit = 0; unit < MAX_DRIVES; unit++) {
- struct gendisk *disk = hwif->drives[unit].disk;
- hwif->drives[unit].disk = NULL;
+ struct gendisk *disk = &hwif->drives[unit].disk;
put_disk(disk);
}
-out:
unregister_blkdev(hwif->major, hwif->name);
return 0;
}
diff -u -r linux/drivers/ide.bak/ide-tape.c linux/drivers/ide/ide-tape.c
--- linux/drivers/ide.bak/ide-tape.c 2002-11-04 21:38:05.000000000 -0800
+++ linux/drivers/ide/ide-tape.c 2002-11-06 05:40:22.000000000 -0800
@@ -6123,7 +6123,7 @@
devfs_unregister(tape->de_r);
devfs_unregister(tape->de_n);
kfree (tape);
- drive->disk->fops = ide_fops;
+ drive->disk.fops = ide_fops;
return 0;
}
@@ -6270,7 +6270,7 @@
S_IFCHR | S_IRUGO | S_IWUGO,
&idetape_fops, NULL);
devfs_register_tape(tape->de_r);
- drive->disk->fops = &idetape_block_ops;
+ drive->disk.fops = &idetape_block_ops;
return 0;
failed:
return 1;
diff -u -r linux/drivers/ide.bak/ide-taskfile.c linux/drivers/ide/ide-taskfile.c
--- linux/drivers/ide.bak/ide-taskfile.c 2002-11-04 21:38:05.000000000 -0800
+++ linux/drivers/ide/ide-taskfile.c 2002-11-06 05:40:06.000000000 -0800
@@ -1356,7 +1356,7 @@
rq->special = args;
rq->errors = 0;
rq->rq_status = RQ_ACTIVE;
- rq->rq_disk = drive->disk;
+ rq->rq_disk = &drive->disk;
rq->waiting = &wait;
spin_lock_irqsave(&ide_lock, flags);
diff -u -r linux/drivers/ide.bak/ide.c linux/drivers/ide/ide.c
--- linux/drivers/ide.bak/ide.c 2002-11-04 21:42:37.000000000 -0800
+++ linux/drivers/ide/ide.c 2002-11-06 05:45:50.000000000 -0800
@@ -1533,7 +1533,7 @@
rq->errors = 0;
rq->rq_status = RQ_ACTIVE;
- rq->rq_disk = drive->disk;
+ rq->rq_disk = &drive->disk;
/*
* we need to hold an extra reference to request for safe inspection
@@ -1774,9 +1774,7 @@
*/
blk_unregister_region(MKDEV(hwif->major, 0), MAX_DRIVES<<PARTN_BITS);
for (i = 0; i < MAX_DRIVES; i++) {
- struct gendisk *disk = hwif->drives[i].disk;
- hwif->drives[i].disk = NULL;
- put_disk(disk);
+ put_disk(&hwif->drives[i].disk);
}
unregister_blkdev(hwif->major, hwif->name);
old_hwif = *hwif;
--vtzGhvizbBRQ85DL--
-
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