This allows userspace to completely setup a loop device with a single
ioctl, removing the in-between state where the device can be partially
configured - eg the loop device has a backing file associated with it,
but is reading from the wrong offset.
Besides removing the intermediate state, another big benefit of this
ioctl is that LOOP_SET_STATUS can be slow; the main reason for this
slowness is that LOOP_SET_STATUS(64) calls blk_mq_freeze_queue() to
freeze the associated queue; this requires waiting for RCU
synchronization, which I've measured can take about 15-20ms on this
device on average.
In addition to doing what LOOP_SET_STATUS can do, LOOP_CONFIGURE can
also be used to:
- Set the correct block size immediately by setting
loop_config.block_size (avoids LOOP_SET_BLOCK_SIZE)
- Explicitly request direct I/O mode by setting LO_FLAGS_DIRECT_IO
in loop_config.info.lo_flags (avoids LOOP_SET_DIRECT_IO)
- Explicitly request read-only mode by setting LO_FLAGS_READ_ONLY
in loop_config.info.lo_flags
Here's setting up ~70 regular loop devices with an offset on an x86
Android device, using LOOP_SET_FD and LOOP_SET_STATUS:
vsoc_x86:/system/apex # time for i in `seq 30 100`;
do losetup -r -o 4096 /dev/block/loop$i com.android.adbd.apex; done
0m03.40s real 0m00.02s user 0m00.03s system
Here's configuring ~70 devices in the same way, but using a modified
losetup that uses the new LOOP_CONFIGURE ioctl:
vsoc_x86:/system/apex # time for i in `seq 30 100`;
do losetup -r -o 4096 /dev/block/loop$i com.android.adbd.apex; done
0m01.94s real 0m00.01s user 0m00.01s system
Signed-off-by: Martijn Coenen <maco@android.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
LOOP_SET_STATUS(64) will actually allow some lo_flags to be modified; in
particular, LO_FLAGS_AUTOCLEAR can be set and cleared, whereas
LO_FLAGS_PARTSCAN can be set to request a partition scan. Make this
explicit by updating the UAPI to include the flags that can be
set/cleared using this ioctl.
The implementation can then blindly take over the passed in flags,
and use the previous flags for those flags that can't be set / cleared
using LOOP_SET_STATUS.
Signed-off-by: Martijn Coenen <maco@android.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In preparation for a new ioctl that needs to copy_from_user(); makes the
code easier to read as well.
Signed-off-by: Martijn Coenen <maco@android.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
So we can use it without forward declaration. This is a separate commit
to make it easier to verify that this is just a move, without functional
modifications.
Signed-off-by: Martijn Coenen <maco@android.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Factor out this code into a separate function, so it can be reused by
other code more easily.
Signed-off-by: Martijn Coenen <maco@android.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This function was now only used by loop_set_capacity(). Just open code
the remaining code in the caller instead.
Signed-off-by: Martijn Coenen <maco@android.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
figure_loop_size() calculates the loop size based on the passed in
parameters, but at the same time it updates the offset and sizelimit
parameters in the loop device configuration. That is a somewhat
unexpected side effect of a function with this name, and it is only only
needed by one of the two callers of this function - loop_set_status().
Move the lo_offset and lo_sizelimit assignment back into loop_set_status(),
and use the newly factored out functions to validate and apply the newly
calculated size. This allows us to get rid of figure_loop_size() in a
follow-up commit.
Signed-off-by: Martijn Coenen <maco@android.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This was recently added to block/genhd.c, and takes care of both
updating the capacity and notifying userspace of the new size.
Signed-off-by: Martijn Coenen <maco@android.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This code is used repeatedly.
Signed-off-by: Martijn Coenen <maco@android.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
sector_t is now always u64, so we don't need to check for truncation.
Signed-off-by: Martijn Coenen <maco@android.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
loop_set_status() calls loop_config_discard() to configure discard for
the loop device; however, the discard configuration depends on whether
the loop device uses encryption, and when we call it the encryption
configuration has not been updated yet. Move the call down so we apply
the correct discard configuration based on the new configuration.
Signed-off-by: Martijn Coenen <maco@android.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When Block Device Layer is disabled, BLK_MAX_SEGMENT_SIZE is undefined.
The rtrs is a transport library and should compile independently of the
block layer. The desired max segment size should be passed down by the
user.
Introduce max_segment_size parameter for the rtrs_clt_open() call.
Fixes: f7a7a5c228 ("block/rnbd: client: main functionality")
Fixes: 6a98d71dae ("RDMA/rtrs: client: main functionality")
Fixes: cb80329c94 ("RDMA/rtrs: client: private header with client structs and functions")
Fixes: b5c27cdb09 ("RDMA/rtrs: public interface header to establish RDMA connections")
Link: https://lore.kernel.org/r/20200519111419.924170-1-danil.kipnis@cloud.ionos.com
Signed-off-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Support REQ_OP_ZONE_APPEND requests for null_blk devices with zoned
mode enabled. Use the internally tracked zone write pointer position
as the actual write position and return it using the command request
__sector field in the case of an mq device and using the command BIO
sector in the case of a BIO device.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Modify the interface of blk_revalidate_disk_zones() to add an optional
driver callback function that a driver can use to extend processing
done during zone revalidation. The callback, if defined, is executed
with the device request queue frozen, after all zones have been
inspected.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
UBSAN: array-index-out-of-bounds in drivers/block/floppy.c:1521:45
index 16 is out of range for type 'unsigned char [16]'
Call Trace:
...
setup_rw_floppy+0x5c3/0x7f0
floppy_ready+0x2be/0x13b0
process_one_work+0x2c1/0x5d0
worker_thread+0x56/0x5e0
kthread+0x122/0x170
ret_from_fork+0x35/0x40
From include/uapi/linux/fd.h:
struct floppy_raw_cmd {
...
unsigned char cmd_count;
unsigned char cmd[16];
unsigned char reply_count;
unsigned char reply[16];
...
}
This out-of-bounds access is intentional. The command in struct
floppy_raw_cmd may take up the space initially intended for the reply
and the reply count. It is needed for long 82078 commands such as
RESTORE, which takes 17 command bytes. Initial cmd size is not enough
and since struct setup_rw_floppy is a part of uapi we check that
cmd_count is in [0:16+1+16] in raw_cmd_copyin().
The patch adds union with original cmd,reply_count,reply fields and
fullcmd field of equivalent size. The cmd accesses are turned to
fullcmd where appropriate to suppress UBSAN warning.
Link: https://lore.kernel.org/r/20200501134416.72248-5-efremov@linux.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Denis Efremov <efremov@linux.com>
Use FD_RAW_CMD_SIZE, FD_RAW_REPLY_SIZE defines instead of magic numbers
for cmd & reply buffers of struct floppy_raw_cmd. Remove local to
floppy.c MAX_REPLIES define, as it is now FD_RAW_REPLY_SIZE.
FD_RAW_CMD_FULLSIZE added as we allow command to also fill reply_count
and reply fields.
Link: https://lore.kernel.org/r/20200501134416.72248-4-efremov@linux.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Denis Efremov <efremov@linux.com>
When called with a negative drive value, set_fdc() would stick to the
current fdc (which was assumed to reflect the current_drive's FDC). We
do not need this anymore as the last call place with a negative value
was just addressed. Let's make this function always set both current_fdc
and current_drive so that there's no more ambiguity. A few comments
stating this were added to a few non-obvious places.
Link: https://lore.kernel.org/r/20200410101904.14652-3-w@1wt.eu
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Denis Efremov <efremov@linux.com>
This macro equals -1 and is used as an alternative for current_drive when
calling reschedule_timeout(), which in turn needs to remap it. This only
adds obfuscation, let's simply use current_drive.
Link: https://lore.kernel.org/r/20200410101904.14652-2-w@1wt.eu
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Denis Efremov <efremov@linux.com>
In floppy_resume() we don't properly reinitialize all FDCs, instead
we reinitialize the current FDC once per available FDC because value
-1 is passed to user_reset_fdc(). Let's simply save the current drive
and properly reinitialize each FDC.
Link: https://lore.kernel.org/r/20200410101904.14652-1-w@1wt.eu
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Denis Efremov <efremov@linux.com>
There's no need to iterate on current_fdc in do_floppy_init() anymore,
in the first case it's only used as an array index to access fdc_state[],
so let's get rid of this confusing assignment. The second case is a bit
trickier because user_reset_fdc() needs to already know current_fdc when
called with drive==-1 due to this call chain:
user_reset_fdc()
lock_fdc()
set_fdc()
drive<0 ==> new_fdc = current_fdc
Note that current_drive is not used in this code part and may even not
match a unit belonging to current_fdc. Instead of passing -1 we can
simply pass the first drive of the FDC being initialized, which is even
cleaner as it will allow the function chain above to consistently assign
both variables.
Link: https://lore.kernel.org/r/20200410093023.14499-1-w@1wt.eu
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Denis Efremov <efremov@linux.com>
The locking in the driver is far from being obvious, with unlocking
automatically happening at end of operations scheduled by interrupt,
especially for the error paths where one does not necessarily expect
that such an interrupt may be triggered. Let's add a few comments
about what to expect at certain places to avoid misdetecting bugs
which are not.
Link: https://lore.kernel.org/r/20200331094054.24441-24-w@1wt.eu
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Denis Efremov <efremov@linux.com>
Both floppy_grab_irq_and_dma() and floppy_release_irq_and_dma() used to
iterate on the global variable while setting up or freeing resources.
Now that they exclusively rely on functions which take the fdc as an
argument, so let's not touch the global one anymore.
Link: https://lore.kernel.org/r/20200331094054.24441-23-w@1wt.eu
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Denis Efremov <efremov@linux.com>
Now the fdc is passed in argument so that the function does not
use current_fdc anymore.
It's worth noting that there's still a single raw_cmd pointer
specific to the current fdc. It may make sense to have one per
fdc in the future. In addition, cont->done() still relies on the
current drive and current raw_cmd.
Link: https://lore.kernel.org/r/20200331094054.24441-17-w@1wt.eu
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Denis Efremov <efremov@linux.com>
Now the fdc is passed in argument so that the function does not
use current_fdc anymore.
It's worth noting that there's still a single reply_buffer[] which
will store the result for the current fdc. It may or may not make
sense to implement one buffer per fdc in the future.
Link: https://lore.kernel.org/r/20200331094054.24441-15-w@1wt.eu
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Denis Efremov <efremov@linux.com>
Chaitanya Kulkarni