similar to: [PATCH RFC] virtio_blk: fix config handler race

Print the capacity of the block device when the driver is probed. Many users expect this since SCSI disks (sd) do it. Moreover, kernel dmesg output is the primary source of troubleshooting information so it's helpful to include the disk size there. The capacity is already printed by virtio_blk when a resize event occurs. Extract the code and reuse it from virtblk_probe(). This patch also

When virtio-blk device is resized from host (using block_resize from QEMU) emit KOBJ_CHANGE uevent to notify guest about such change. This allows user to have custom udev rules which would take whatever action if such event occurs. As a proof of concept I've created simple udev rule that automatically resize filesystem on virtio-blk device. ACTION=="change", KERNEL=="vd*",

When virtio-blk device is resized from host (using block_resize from QEMU) emit KOBJ_CHANGE uevent to notify guest about such change. This allows user to have custom udev rules which would take whatever action if such event occurs. As a proof of concept I've created simple udev rule that automatically resize filesystem on virtio-blk device. ACTION=="change", KERNEL=="vd*",

The message printed on disk resize is incorrect. The following is printed when resizing to 2 GiB: $ truncate -s 1G test.img $ qemu -device virtio-blk-pci,logical_block_size=4096,... (qemu) block_resize drive1 2G virtio_blk virtio0: new size: 4194304 4096-byte logical blocks (17.2 GB/16.0 GiB) The virtio_blk capacity config field is in 512-byte sector units regardless of

The message printed on disk resize is incorrect. The following is printed when resizing to 2 GiB: $ truncate -s 1G test.img $ qemu -device virtio-blk-pci,logical_block_size=4096,... (qemu) block_resize drive1 2G virtio_blk virtio0: new size: 4194304 4096-byte logical blocks (17.2 GB/16.0 GiB) The virtio_blk capacity config field is in 512-byte sector units regardless of

Now that virtio core ensures config changes don't arrive during probing, drop config_enable flag in virtio blk. On removal, flush is now sufficient to guarantee that no change work is queued. This help simplify the driver, and will allow setting DRIVER_OK earlier without losing config change notifications. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> ---

Now that virtio core ensures config changes don't arrive during probing, drop config_enable flag in virtio blk. On removal, flush is now sufficient to guarantee that no change work is queued. This help simplify the driver, and will allow setting DRIVER_OK earlier without losing config change notifications. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> ---

config_mutex served two purposes: prevent multiple concurrent config change handlers, and synchronize access to config_enable flag. Since commit dbf2576e37da0fcc7aacbfbb9fd5d3de7888a3c1 workqueue: make all workqueues non-reentrant all workqueues are non-reentrant, and config_enable is now gone. Get rid of the unnecessary lock. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> ---

On Sun, 5 Oct 2014 19:07:07 +0300 "Michael S. Tsirkin" <mst at redhat.com> wrote: > Now that virtio core ensures config changes don't > arrive during probing, drop config_enable flag > in virtio blk. > On removal, flush is now sufficient to guarantee that > no change work is queued. > > This help simplify the driver, and will allow > setting DRIVER_OK

On Sun, 5 Oct 2014 19:07:07 +0300 "Michael S. Tsirkin" <mst at redhat.com> wrote: > Now that virtio core ensures config changes don't > arrive during probing, drop config_enable flag > in virtio blk. > On removal, flush is now sufficient to guarantee that > no change work is queued. > > This help simplify the driver, and will allow > setting DRIVER_OK

If we reset the virtio-blk device before the requests already dispatched to the virtio-blk driver from the block layer are finised, we will stuck in blk_cleanup_queue() and the remove will fail. blk_cleanup_queue() calls blk_drain_queue() to drain all requests queued before DEAD marking. However it will never success if the device is already stopped. We'll have q->in_flight[] > 0, so

If we reset the virtio-blk device before the requests already dispatched to the virtio-blk driver from the block layer are finised, we will stuck in blk_cleanup_queue() and the remove will fail. blk_cleanup_queue() calls blk_drain_queue() to drain all requests queued before DEAD marking. However it will never success if the device is already stopped. We'll have q->in_flight[] > 0, so

Rusty, I have a mind to send this patches for the next merge window. Any input on this? This fixes the following virtio spec compliance issues: 1. on restore, drivers use device before setting ACKNOWLEDGE and DRIVER bits 2. on probe, drivers aren't prepared to handle config interrupts arriving before probe returns 3. on probe, drivers use device before DRIVER_OK it set Note that 1 is a

Rusty, I have a mind to send this patches for the next merge window. Any input on this? This fixes the following virtio spec compliance issues: 1. on restore, drivers use device before setting ACKNOWLEDGE and DRIVER bits 2. on probe, drivers aren't prepared to handle config interrupts arriving before probe returns 3. on probe, drivers use device before DRIVER_OK it set Note that 1 is a

Rusty, I have a mind to include this patchset for this merge window. Any input on this? This fixes the following virtio spec compliance issues: 1. on restore, drivers use device before setting ACKNOWLEDGE and DRIVER bits 2. on probe, drivers aren't prepared to handle config interrupts arriving before probe returns 3. on probe, drivers use device before DRIVER_OK it set Note that 1 is a

Rusty, I have a mind to include this patchset for this merge window. Any input on this? This fixes the following virtio spec compliance issues: 1. on restore, drivers use device before setting ACKNOWLEDGE and DRIVER bits 2. on probe, drivers aren't prepared to handle config interrupts arriving before probe returns 3. on probe, drivers use device before DRIVER_OK it set Note that 1 is a

Rusty, please review this, and consider for this merge window. This fixes the following virtio spec compliance issues: 1. on restore, drivers use device before setting ACKNOWLEDGE and DRIVER bits 2. on probe, drivers aren't prepared to handle config interrupts arriving before probe returns 3. on probe, drivers use device before DRIVER_OK it set Note that 1 is a clear violation of virtio

Rusty, please review this, and consider for this merge window. This fixes the following virtio spec compliance issues: 1. on restore, drivers use device before setting ACKNOWLEDGE and DRIVER bits 2. on probe, drivers aren't prepared to handle config interrupts arriving before probe returns 3. on probe, drivers use device before DRIVER_OK it set Note that 1 is a clear violation of virtio

This patch adds support for an optional stats vq that works similary to the stats vq provided by virtio-balloon. The purpose of this change is to allow collection of statistics about working virtio-blk devices to easily analyze performance without having to tap into the guest. Cc: Rusty Russell <rusty at rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst at redhat.com> Cc:

This patch adds support for an optional stats vq that works similary to the stats vq provided by virtio-balloon. The purpose of this change is to allow collection of statistics about working virtio-blk devices to easily analyze performance without having to tap into the guest. Cc: Rusty Russell <rusty at rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst at redhat.com> Cc: