search for: virtio_blk_f_discard

Currently virtio-blk driver does not provide discard feature flag, so the filesystems which built on top of the block device will not send discard command. This is okay for HDD backend, but it will impact the performance for SSD backend. Add a feature flag VIRTIO_BLK_F_DISCARD and command VIRTIO_BLK_T_DISCARD to extend exist virtio-blk protocol, define 16 bytes discard descriptor for each discard segment, the discard segment defination aligns with SCSI or NVM Express protocols, virtio-blk driver will support multi-range discard request as well. Signed-off-by: Changpeng...

Currently virtio-blk driver does not provide discard feature flag, so the filesystems which built on top of the block device will not send discard command. This is okay for HDD backend, but it will impact the performance for SSD backend. Add a feature flag VIRTIO_BLK_F_DISCARD and command VIRTIO_BLK_T_DISCARD to extend exist virtio-blk protocol, define 16 bytes discard descriptor for each discard segment, the discard segment defination aligns with SCSI or NVM Express protocols, virtio-blk driver will support multi-range discard request as well. Signed-off-by: Changpeng...

...E ZEROES command support, this will impact the performance when using SSD backend over file systems. The idea here is using 16 Bytes payload as one descriptor for DISCARD/WRITE ZEROES command, users can put several ranges into one command, for the purpose to support such feature, two feature flags VIRTIO_BLK_F_DISCARD/VIRTIO_BLK_F_WRITE_ZEROES and two commands VIRTIO_BLK_T_DISCARD/VIRTIO_BLK_T_WRITE_ZEROES are introduced, and some parameters are added to the configuration space to tell the OS the granularity of DISCARD/WRITE ZEROES commands. The specification change list here: https://github.com/oasis-tcs/virti...

...E ZEROES command support, this will impact the performance when using SSD backend over file systems. The idea here is using 16 Bytes payload as one descriptor for DISCARD/WRITE ZEROES command, users can put several ranges into one command, for the purpose to support such feature, two feature flags VIRTIO_BLK_F_DISCARD/VIRTIO_BLK_F_WRITE_ZEROES and two commands VIRTIO_BLK_T_DISCARD/VIRTIO_BLK_T_WRITE_ZEROES are introduced, and some parameters are added to the configuration space to tell the OS the granularity of DISCARD/WRITE ZEROES commands. The specification change list here: https://github.com/oasis-tcs/virti...

Currently virtio-blk driver does not provide discard feature flag, so the filesystems which built on top of the block device will not send discard command. This is okay for HDD backend, but it will impact the performance for SSD backend. Add a feature flag VIRTIO_BLK_F_DISCARD and command VIRTIO_BLK_T_DISCARD to extend exist virtio-blk protocol. virtio-blk protocol uses a single 8 bytes descriptor containing type,reserved and sector, currently Linux uses the reserved field as IO priority, here we also re-use the reserved field as number of discard sectors. Signed-off-by...

Currently virtio-blk driver does not provide discard feature flag, so the filesystems which built on top of the block device will not send discard command. This is okay for HDD backend, but it will impact the performance for SSD backend. Add a feature flag VIRTIO_BLK_F_DISCARD and command VIRTIO_BLK_T_DISCARD to extend exist virtio-blk protocol. virtio-blk protocol uses a single 8 bytes descriptor containing type,reserved and sector, currently Linux uses the reserved field as IO priority, here we also re-use the reserved field as number of discard sectors. Signed-off-by...

...onfiguration parameters. struct virtio_blk_config { [...] le32 max_discard_sectors; le32 max_discard_seg; le32 discard_sector_alignment; le32 max_write_zeroes_sectors; le32 max_write_zeroes_seg; u8 write_zeroes_may_unmap; } New feature bit [VIRTIO_BLK_F_DISCARD (13)]: Device can support discard command, maximum discard sectors size in field 'max_discard_sectors' and maximum discard segment number in field 'max_discard_seg'. New feature [VIRTIO_BLK_F_WRITE_ZEROES (14)]: Device can support write zeroes command, maximum write zeroes sectors...

...onfiguration parameters. struct virtio_blk_config { [...] le32 max_discard_sectors; le32 max_discard_seg; le32 discard_sector_alignment; le32 max_write_zeroes_sectors; le32 max_write_zeroes_seg; u8 write_zeroes_may_unmap; } New feature bit [VIRTIO_BLK_F_DISCARD (13)]: Device can support discard command, maximum discard sectors size in field 'max_discard_sectors' and maximum discard segment number in field 'max_discard_seg'. New feature [VIRTIO_BLK_F_WRITE_ZEROES (14)]: Device can support write zeroes command, maximum write zeroes sectors...

...onfiguration parameters. struct virtio_blk_config { [...] le32 max_discard_sectors; le32 max_discard_seg; le32 discard_sector_alignment; le32 max_write_zeroes_sectors; le32 max_write_zeroes_seg; u8 write_zeroes_may_unmap; } New feature bit [VIRTIO_BLK_F_DISCARD (13)]: Device can support discard command, maximum discard sectors size in field 'max_discard_sectors' and maximum discard segment number in field 'max_discard_seg'. New feature [VIRTIO_BLK_F_WRITE_ZEROES (14)]: Device can support write zeroes command, maximum write zeroes sectors...

...onfiguration parameters. struct virtio_blk_config { [...] le32 max_discard_sectors; le32 max_discard_seg; le32 discard_sector_alignment; le32 max_write_zeroes_sectors; le32 max_write_zeroes_seg; u8 write_zeroes_may_unmap; } New feature bit [VIRTIO_BLK_F_DISCARD (13)]: Device can support discard command, maximum discard sectors size in field 'max_discard_sectors' and maximum discard segment number in field 'max_discard_seg'. New feature [VIRTIO_BLK_F_WRITE_ZEROES (14)]: Device can support write zeroes command, maximum write zeroes sectors...

...ly virtio-blk driver does not provide discard feature flag, so the > > filesystems which built on top of the block device will not send discard > > command. This is okay for HDD backend, but it will impact the performance > > for SSD backend. > > > > Add a feature flag VIRTIO_BLK_F_DISCARD and command > VIRTIO_BLK_T_DISCARD > > to extend exist virtio-blk protocol. virtio-blk protocol uses a single > > 8 bytes descriptor containing type,reserved and sector, currently Linux > > uses the reserved field as IO priority, here we also re-use the reserved > > field...

...ly virtio-blk driver does not provide discard feature flag, so the > > filesystems which built on top of the block device will not send discard > > command. This is okay for HDD backend, but it will impact the performance > > for SSD backend. > > > > Add a feature flag VIRTIO_BLK_F_DISCARD and command > VIRTIO_BLK_T_DISCARD > > to extend exist virtio-blk protocol. virtio-blk protocol uses a single > > 8 bytes descriptor containing type,reserved and sector, currently Linux > > uses the reserved field as IO priority, here we also re-use the reserved > > field...

...Liu wrote: > Currently virtio-blk driver does not provide discard feature flag, so the > filesystems which built on top of the block device will not send discard > command. This is okay for HDD backend, but it will impact the performance > for SSD backend. > > Add a feature flag VIRTIO_BLK_F_DISCARD and command VIRTIO_BLK_T_DISCARD > to extend exist virtio-blk protocol, define 16 bytes discard descriptor > for each discard segment, the discard segment defination aligns with > SCSI or NVM Express protocols, virtio-blk driver will support multi-range > discard request as well. >...

...will impact the performance when using SSD > backend over file systems. > > The idea here is using 16 Bytes payload as one descriptor for > DISCARD/WRITE ZEROES command, users can put several ranges into > one command, for the purpose to support such feature, two feature > flags VIRTIO_BLK_F_DISCARD/VIRTIO_BLK_F_WRITE_ZEROES and two > commands VIRTIO_BLK_T_DISCARD/VIRTIO_BLK_T_WRITE_ZEROES are > introduced, and some parameters are added to the configuration > space to tell the OS the granularity of DISCARD/WRITE ZEROES > commands. Pls fix grammar in this comment, I am not sure wha...

...onfiguration parameters. struct virtio_blk_config { [...] le32 max_discard_sectors; le32 max_discard_seg; le32 discard_sector_alignment; le32 max_write_zeroes_sectors; le32 max_write_zeroes_seg; u8 write_zeroes_may_unmap; } New feature bit [VIRTIO_BLK_F_DISCARD (13)]: Device can support discard command, maximum discard sectors size in field 'max_discard_sectors' and maximum discard segment number in field 'max_discard_seg'. New feature [VIRTIO_BLK_F_WRITE_ZEROES (14)]: Device can support write zeroes command, maximum write zeroes sectors...

...onfiguration parameters. struct virtio_blk_config { [...] le32 max_discard_sectors; le32 max_discard_seg; le32 discard_sector_alignment; le32 max_write_zeroes_sectors; le32 max_write_zeroes_seg; u8 write_zeroes_may_unmap; } New feature bit [VIRTIO_BLK_F_DISCARD (13)]: Device can support discard command, maximum discard sectors size in field 'max_discard_sectors' and maximum discard segment number in field 'max_discard_seg'. New feature [VIRTIO_BLK_F_WRITE_ZEROES (14)]: Device can support write zeroes command, maximum write zeroes sectors...

...ly virtio-blk driver does not provide discard feature flag, so the > > filesystems which built on top of the block device will not send discard > > command. This is okay for HDD backend, but it will impact the performance > > for SSD backend. > > > > Add a feature flag VIRTIO_BLK_F_DISCARD and command > VIRTIO_BLK_T_DISCARD > > to extend exist virtio-blk protocol, define 16 bytes discard descriptor > > for each discard segment, the discard segment defination aligns with > > SCSI or NVM Express protocols, virtio-blk driver will support multi-range > > discar...

...ly virtio-blk driver does not provide discard feature flag, so the > > filesystems which built on top of the block device will not send discard > > command. This is okay for HDD backend, but it will impact the performance > > for SSD backend. > > > > Add a feature flag VIRTIO_BLK_F_DISCARD and command > VIRTIO_BLK_T_DISCARD > > to extend exist virtio-blk protocol, define 16 bytes discard descriptor > > for each discard segment, the discard segment defination aligns with > > SCSI or NVM Express protocols, virtio-blk driver will support multi-range > > discar...

...m/oasis-tcs/virtio-spec), the virtio > block specification has been extended to add VIRTIO_BLK_T_DISCARD and > VIRTIO_BLK_T_WRITE_ZEROES commands. This patch enables support for > discard and write zeroes in the virtio-blk driver when the device > advertises the corresponding features, VIRTIO_BLK_F_DISCARD and > VIRTIO_BLK_F_WRITE_ZEROES. > > Signed-off-by: Changpeng Liu <changpeng.liu at intel.com> > Signed-off-by: Daniel Verkamp <dverkamp at chromium.org> > --- > dverkamp: I've picked up this patch and made a few minor changes (as > listed below); most notably,...

...Liu wrote: > Currently virtio-blk driver does not provide discard feature flag, so the > filesystems which built on top of the block device will not send discard > command. This is okay for HDD backend, but it will impact the performance > for SSD backend. > > Add a feature flag VIRTIO_BLK_F_DISCARD and command VIRTIO_BLK_T_DISCARD > to extend exist virtio-blk protocol. virtio-blk protocol uses a single > 8 bytes descriptor containing type,reserved and sector, currently Linux > uses the reserved field as IO priority, here we also re-use the reserved > field as number of discard sec...