Re: [PATCH 15/19] amiflop: use separate gendisks for Amiga vs MS-DOS mode

2020-09-04 Thread Hannes Reinecke

On 9/3/20 10:01 AM, Christoph Hellwig wrote:

Use separate gendisks (which share a tag_set) for the native Amgiga vs
the MS-DOS mode instead of redirecting the gendisk lookup using a probe
callback.  This avoids potential problems with aliased block_device
instances and will eventually allow for removing the blk_register_region
framework.

Signed-off-by: Christoph Hellwig 
---
  drivers/block/amiflop.c | 98 +++--
  1 file changed, 55 insertions(+), 43 deletions(-)


Reviewed-by: Hannes Reinecke 

Cheers,

Hannes
--
Dr. Hannes ReineckeKernel Storage Architect
h...@suse.de  +49 911 74053 688
SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg
HRB 36809 (AG Nürnberg), Geschäftsführer: Felix Imendörffer


[PATCH 15/19] amiflop: use separate gendisks for Amiga vs MS-DOS mode

2020-09-03 Thread Christoph Hellwig
Use separate gendisks (which share a tag_set) for the native Amgiga vs
the MS-DOS mode instead of redirecting the gendisk lookup using a probe
callback.  This avoids potential problems with aliased block_device
instances and will eventually allow for removing the blk_register_region
framework.

Signed-off-by: Christoph Hellwig 
---
 drivers/block/amiflop.c | 98 +++--
 1 file changed, 55 insertions(+), 43 deletions(-)

diff --git a/drivers/block/amiflop.c b/drivers/block/amiflop.c
index 226219da3da6a7..de2bad8d1512f2 100644
--- a/drivers/block/amiflop.c
+++ b/drivers/block/amiflop.c
@@ -201,7 +201,7 @@ struct amiga_floppy_struct {
int busy;   /* true when drive is active */
int dirty;  /* true when trackbuf is not on disk */
int status; /* current error code for unit */
-   struct gendisk *gendisk;
+   struct gendisk *gendisk[2];
struct blk_mq_tag_set tag_set;
 };
 
@@ -1669,6 +1669,11 @@ static int floppy_open(struct block_device *bdev, 
fmode_t mode)
return -EBUSY;
}
 
+   if (unit[drive].type->code == FD_NODRIVE) {
+   mutex_unlock(_mutex);
+   return -ENXIO;
+   }
+
if (mode & (FMODE_READ|FMODE_WRITE)) {
check_disk_change(bdev);
if (mode & FMODE_WRITE) {
@@ -1695,7 +1700,7 @@ static int floppy_open(struct block_device *bdev, fmode_t 
mode)
unit[drive].dtype=_types[system];
unit[drive].blocks=unit[drive].type->heads*unit[drive].type->tracks*
data_types[system].sects*unit[drive].type->sect_mult;
-   set_capacity(unit[drive].gendisk, unit[drive].blocks);
+   set_capacity(unit[drive].gendisk[system], unit[drive].blocks);
 
printk(KERN_INFO "fd%d: accessing %s-disk with %s-layout\n",drive,
   unit[drive].type->name, data_types[system].name);
@@ -1772,36 +1777,68 @@ static const struct blk_mq_ops amiflop_mq_ops = {
.queue_rq = amiflop_queue_rq,
 };
 
-static struct gendisk *fd_alloc_disk(int drive)
+static int fd_alloc_disk(int drive, int system)
 {
struct gendisk *disk;
 
disk = alloc_disk(1);
if (!disk)
goto out;
-
-   disk->queue = blk_mq_init_sq_queue([drive].tag_set, 
_mq_ops,
-   2, BLK_MQ_F_SHOULD_MERGE);
-   if (IS_ERR(disk->queue)) {
-   disk->queue = NULL;
+   disk->queue = blk_mq_init_queue([drive].tag_set);
+   if (IS_ERR(disk->queue))
goto out_put_disk;
-   }
 
+   disk->major = FLOPPY_MAJOR;
+   disk->first_minor = drive + system;
+   disk->fops = _fops;
+   disk->events = DISK_EVENT_MEDIA_CHANGE;
+   if (system)
+   sprintf(disk->disk_name, "fd%d_msdos", drive);
+   else
+   sprintf(disk->disk_name, "fd%d", drive);
+   disk->private_data = [drive];
+   set_capacity(disk, 880 * 2);
+
+   unit[drive].gendisk[system] = disk;
+   add_disk(disk);
+   return 0;
+
+out_put_disk:
+   disk->queue = NULL;
+   put_disk(disk);
+out:
+   return -ENOMEM;
+}
+
+static int fd_alloc_drive(int drive)
+{
unit[drive].trackbuf = kmalloc(FLOPPY_MAX_SECTORS * 512, GFP_KERNEL);
if (!unit[drive].trackbuf)
-   goto out_cleanup_queue;
+   goto out;
 
-   return disk;
+   memset([drive].tag_set, 0, sizeof(unit[drive].tag_set));
+   unit[drive].tag_set.ops = _mq_ops;
+   unit[drive].tag_set.nr_hw_queues = 1;
+   unit[drive].tag_set.nr_maps = 1;
+   unit[drive].tag_set.queue_depth = 2;
+   unit[drive].tag_set.numa_node = NUMA_NO_NODE;
+   unit[drive].tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
+   if (blk_mq_alloc_tag_set([drive].tag_set))
+   goto out_cleanup_trackbuf;
 
-out_cleanup_queue:
-   blk_cleanup_queue(disk->queue);
-   disk->queue = NULL;
+   pr_cont(" fd%d", drive);
+
+   if (fd_alloc_disk(drive, 0) || fd_alloc_disk(drive, 1))
+   goto out_cleanup_tagset;
+   return 0;
+
+out_cleanup_tagset:
blk_mq_free_tag_set([drive].tag_set);
-out_put_disk:
-   put_disk(disk);
+out_cleanup_trackbuf:
+   kfree(unit[drive].trackbuf);
 out:
unit[drive].type->code = FD_NODRIVE;
-   return NULL;
+   return -ENOMEM;
 }
 
 static int __init fd_probe_drives(void)
@@ -1812,29 +1849,16 @@ static int __init fd_probe_drives(void)
drives=0;
nomem=0;
for(drive=0;drivecode == FD_NODRIVE)
continue;
 
-   disk = fd_alloc_disk(drive);
-   if (!disk) {
+   if (fd_alloc_drive(drive) < 0) {
pr_cont(" no mem for fd%d", drive);
nomem = 1;
continue;
}
-   unit[drive].gendisk = disk;
drives++;
-
-  

[PATCH 15/19] amiflop: use separate gendisks for Amiga vs MS-DOS mode

2020-08-30 Thread Christoph Hellwig
Use separate gendisks (which share a tag_set) for the native Amgiga vs
the MS-DOS mode instead of redirecting the gendisk lookup using a probe
callback.  This avoids potential problems with aliased block_device
instances and will eventually allow for removing the blk_register_region
framework.

Signed-off-by: Christoph Hellwig 
---
 drivers/block/amiflop.c | 98 +++--
 1 file changed, 55 insertions(+), 43 deletions(-)

diff --git a/drivers/block/amiflop.c b/drivers/block/amiflop.c
index 226219da3da6a7..de2bad8d1512f2 100644
--- a/drivers/block/amiflop.c
+++ b/drivers/block/amiflop.c
@@ -201,7 +201,7 @@ struct amiga_floppy_struct {
int busy;   /* true when drive is active */
int dirty;  /* true when trackbuf is not on disk */
int status; /* current error code for unit */
-   struct gendisk *gendisk;
+   struct gendisk *gendisk[2];
struct blk_mq_tag_set tag_set;
 };
 
@@ -1669,6 +1669,11 @@ static int floppy_open(struct block_device *bdev, 
fmode_t mode)
return -EBUSY;
}
 
+   if (unit[drive].type->code == FD_NODRIVE) {
+   mutex_unlock(_mutex);
+   return -ENXIO;
+   }
+
if (mode & (FMODE_READ|FMODE_WRITE)) {
check_disk_change(bdev);
if (mode & FMODE_WRITE) {
@@ -1695,7 +1700,7 @@ static int floppy_open(struct block_device *bdev, fmode_t 
mode)
unit[drive].dtype=_types[system];
unit[drive].blocks=unit[drive].type->heads*unit[drive].type->tracks*
data_types[system].sects*unit[drive].type->sect_mult;
-   set_capacity(unit[drive].gendisk, unit[drive].blocks);
+   set_capacity(unit[drive].gendisk[system], unit[drive].blocks);
 
printk(KERN_INFO "fd%d: accessing %s-disk with %s-layout\n",drive,
   unit[drive].type->name, data_types[system].name);
@@ -1772,36 +1777,68 @@ static const struct blk_mq_ops amiflop_mq_ops = {
.queue_rq = amiflop_queue_rq,
 };
 
-static struct gendisk *fd_alloc_disk(int drive)
+static int fd_alloc_disk(int drive, int system)
 {
struct gendisk *disk;
 
disk = alloc_disk(1);
if (!disk)
goto out;
-
-   disk->queue = blk_mq_init_sq_queue([drive].tag_set, 
_mq_ops,
-   2, BLK_MQ_F_SHOULD_MERGE);
-   if (IS_ERR(disk->queue)) {
-   disk->queue = NULL;
+   disk->queue = blk_mq_init_queue([drive].tag_set);
+   if (IS_ERR(disk->queue))
goto out_put_disk;
-   }
 
+   disk->major = FLOPPY_MAJOR;
+   disk->first_minor = drive + system;
+   disk->fops = _fops;
+   disk->events = DISK_EVENT_MEDIA_CHANGE;
+   if (system)
+   sprintf(disk->disk_name, "fd%d_msdos", drive);
+   else
+   sprintf(disk->disk_name, "fd%d", drive);
+   disk->private_data = [drive];
+   set_capacity(disk, 880 * 2);
+
+   unit[drive].gendisk[system] = disk;
+   add_disk(disk);
+   return 0;
+
+out_put_disk:
+   disk->queue = NULL;
+   put_disk(disk);
+out:
+   return -ENOMEM;
+}
+
+static int fd_alloc_drive(int drive)
+{
unit[drive].trackbuf = kmalloc(FLOPPY_MAX_SECTORS * 512, GFP_KERNEL);
if (!unit[drive].trackbuf)
-   goto out_cleanup_queue;
+   goto out;
 
-   return disk;
+   memset([drive].tag_set, 0, sizeof(unit[drive].tag_set));
+   unit[drive].tag_set.ops = _mq_ops;
+   unit[drive].tag_set.nr_hw_queues = 1;
+   unit[drive].tag_set.nr_maps = 1;
+   unit[drive].tag_set.queue_depth = 2;
+   unit[drive].tag_set.numa_node = NUMA_NO_NODE;
+   unit[drive].tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
+   if (blk_mq_alloc_tag_set([drive].tag_set))
+   goto out_cleanup_trackbuf;
 
-out_cleanup_queue:
-   blk_cleanup_queue(disk->queue);
-   disk->queue = NULL;
+   pr_cont(" fd%d", drive);
+
+   if (fd_alloc_disk(drive, 0) || fd_alloc_disk(drive, 1))
+   goto out_cleanup_tagset;
+   return 0;
+
+out_cleanup_tagset:
blk_mq_free_tag_set([drive].tag_set);
-out_put_disk:
-   put_disk(disk);
+out_cleanup_trackbuf:
+   kfree(unit[drive].trackbuf);
 out:
unit[drive].type->code = FD_NODRIVE;
-   return NULL;
+   return -ENOMEM;
 }
 
 static int __init fd_probe_drives(void)
@@ -1812,29 +1849,16 @@ static int __init fd_probe_drives(void)
drives=0;
nomem=0;
for(drive=0;drivecode == FD_NODRIVE)
continue;
 
-   disk = fd_alloc_disk(drive);
-   if (!disk) {
+   if (fd_alloc_drive(drive) < 0) {
pr_cont(" no mem for fd%d", drive);
nomem = 1;
continue;
}
-   unit[drive].gendisk = disk;
drives++;
-
-  

[PATCH 15/19] amiflop: use separate gendisks for Amiga vs MS-DOS mode

2020-08-26 Thread Christoph Hellwig
Use separate gendisks (which share a tag_set) for the native Amgiga vs
the MS-DOS mode instead of redirecting the gendisk lookup using a probe
callback.  This avoids potential problems with aliased block_device
instances and will eventually allow for removing the blk_register_region
framework.

Signed-off-by: Christoph Hellwig 
---
 drivers/block/amiflop.c | 98 +++--
 1 file changed, 55 insertions(+), 43 deletions(-)

diff --git a/drivers/block/amiflop.c b/drivers/block/amiflop.c
index 226219da3da6a7..de2bad8d1512f2 100644
--- a/drivers/block/amiflop.c
+++ b/drivers/block/amiflop.c
@@ -201,7 +201,7 @@ struct amiga_floppy_struct {
int busy;   /* true when drive is active */
int dirty;  /* true when trackbuf is not on disk */
int status; /* current error code for unit */
-   struct gendisk *gendisk;
+   struct gendisk *gendisk[2];
struct blk_mq_tag_set tag_set;
 };
 
@@ -1669,6 +1669,11 @@ static int floppy_open(struct block_device *bdev, 
fmode_t mode)
return -EBUSY;
}
 
+   if (unit[drive].type->code == FD_NODRIVE) {
+   mutex_unlock(_mutex);
+   return -ENXIO;
+   }
+
if (mode & (FMODE_READ|FMODE_WRITE)) {
check_disk_change(bdev);
if (mode & FMODE_WRITE) {
@@ -1695,7 +1700,7 @@ static int floppy_open(struct block_device *bdev, fmode_t 
mode)
unit[drive].dtype=_types[system];
unit[drive].blocks=unit[drive].type->heads*unit[drive].type->tracks*
data_types[system].sects*unit[drive].type->sect_mult;
-   set_capacity(unit[drive].gendisk, unit[drive].blocks);
+   set_capacity(unit[drive].gendisk[system], unit[drive].blocks);
 
printk(KERN_INFO "fd%d: accessing %s-disk with %s-layout\n",drive,
   unit[drive].type->name, data_types[system].name);
@@ -1772,36 +1777,68 @@ static const struct blk_mq_ops amiflop_mq_ops = {
.queue_rq = amiflop_queue_rq,
 };
 
-static struct gendisk *fd_alloc_disk(int drive)
+static int fd_alloc_disk(int drive, int system)
 {
struct gendisk *disk;
 
disk = alloc_disk(1);
if (!disk)
goto out;
-
-   disk->queue = blk_mq_init_sq_queue([drive].tag_set, 
_mq_ops,
-   2, BLK_MQ_F_SHOULD_MERGE);
-   if (IS_ERR(disk->queue)) {
-   disk->queue = NULL;
+   disk->queue = blk_mq_init_queue([drive].tag_set);
+   if (IS_ERR(disk->queue))
goto out_put_disk;
-   }
 
+   disk->major = FLOPPY_MAJOR;
+   disk->first_minor = drive + system;
+   disk->fops = _fops;
+   disk->events = DISK_EVENT_MEDIA_CHANGE;
+   if (system)
+   sprintf(disk->disk_name, "fd%d_msdos", drive);
+   else
+   sprintf(disk->disk_name, "fd%d", drive);
+   disk->private_data = [drive];
+   set_capacity(disk, 880 * 2);
+
+   unit[drive].gendisk[system] = disk;
+   add_disk(disk);
+   return 0;
+
+out_put_disk:
+   disk->queue = NULL;
+   put_disk(disk);
+out:
+   return -ENOMEM;
+}
+
+static int fd_alloc_drive(int drive)
+{
unit[drive].trackbuf = kmalloc(FLOPPY_MAX_SECTORS * 512, GFP_KERNEL);
if (!unit[drive].trackbuf)
-   goto out_cleanup_queue;
+   goto out;
 
-   return disk;
+   memset([drive].tag_set, 0, sizeof(unit[drive].tag_set));
+   unit[drive].tag_set.ops = _mq_ops;
+   unit[drive].tag_set.nr_hw_queues = 1;
+   unit[drive].tag_set.nr_maps = 1;
+   unit[drive].tag_set.queue_depth = 2;
+   unit[drive].tag_set.numa_node = NUMA_NO_NODE;
+   unit[drive].tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
+   if (blk_mq_alloc_tag_set([drive].tag_set))
+   goto out_cleanup_trackbuf;
 
-out_cleanup_queue:
-   blk_cleanup_queue(disk->queue);
-   disk->queue = NULL;
+   pr_cont(" fd%d", drive);
+
+   if (fd_alloc_disk(drive, 0) || fd_alloc_disk(drive, 1))
+   goto out_cleanup_tagset;
+   return 0;
+
+out_cleanup_tagset:
blk_mq_free_tag_set([drive].tag_set);
-out_put_disk:
-   put_disk(disk);
+out_cleanup_trackbuf:
+   kfree(unit[drive].trackbuf);
 out:
unit[drive].type->code = FD_NODRIVE;
-   return NULL;
+   return -ENOMEM;
 }
 
 static int __init fd_probe_drives(void)
@@ -1812,29 +1849,16 @@ static int __init fd_probe_drives(void)
drives=0;
nomem=0;
for(drive=0;drivecode == FD_NODRIVE)
continue;
 
-   disk = fd_alloc_disk(drive);
-   if (!disk) {
+   if (fd_alloc_drive(drive) < 0) {
pr_cont(" no mem for fd%d", drive);
nomem = 1;
continue;
}
-   unit[drive].gendisk = disk;
drives++;
-
-