Some g_raid tasters attempt metadata reads in multiples of the provider
sectorsize. Reads larger than MAXPHYS are invalid, so detect and abort
in such situations.
Spiritually similar to r217305 / PR 147851.
PR: 214721
Sponsored by: Dell EMC Isilon
Instead opening/closing provider by each of metadata classes, do it only
once in core code. Since for SCSI disks open/close means sending some
SCSI commands to the device, this change reduces taste time.
MFC after: 2 weeks
Sponsored by: iXsystems, Inc.
This caused incorrect behavior of arrays with big-endian DDF metadata.
Little-endian (like used by Adaptec controllers) should not be harmed.
Add workaround should be enough to manage compatibility.
MFC after: 2 weeks
When safety requirements are met, it allows to avoid passing I/O requests
to GEOM g_up/g_down thread, executing them directly in the caller context.
That allows to avoid CPU bottlenecks in g_up/g_down threads, plus avoid
several context switches per I/O.
The defined now safety requirements are:
- caller should not hold any locks and should be reenterable;
- callee should not depend on GEOM dual-threaded concurency semantics;
- on the way down, if request is unmapped while callee doesn't support it,
the context should be sleepable;
- kernel thread stack usage should be below 50%.
To keep compatibility with GEOM classes not meeting above requirements
new provider and consumer flags added:
- G_CF_DIRECT_SEND -- consumer code meets caller requirements (request);
- G_CF_DIRECT_RECEIVE -- consumer code meets callee requirements (done);
- G_PF_DIRECT_SEND -- provider code meets caller requirements (done);
- G_PF_DIRECT_RECEIVE -- provider code meets callee requirements (request).
Capable GEOM class can set them, allowing direct dispatch in cases where
it is safe. If any of requirements are not met, request is queued to
g_up or g_down thread same as before.
Such GEOM classes were reviewed and updated to support direct dispatch:
CONCAT, DEV, DISK, GATE, MD, MIRROR, MULTIPATH, NOP, PART, RAID, STRIPE,
VFS, ZERO, ZFS::VDEV, ZFS::ZVOL, all classes based on g_slice KPI (LABEL,
MAP, FLASHMAP, etc).
To declare direct completion capability disk(9) KPI got new flag equivalent
to G_PF_DIRECT_SEND -- DISKFLAG_DIRECT_COMPLETION. da(4) and ada(4) disk
drivers got it set now thanks to earlier CAM locking work.
This change more then twice increases peak block storage performance on
systems with manu CPUs, together with earlier CAM locking changes reaching
more then 1 million IOPS (512 byte raw reads from 16 SATA SSDs on 4 HBAs to
256 user-level threads).
Sponsored by: iXsystems, Inc.
MFC after: 2 months
If at least one subdisk in the volume supports it, BIO_DELETE requests
will be propagated down. Unfortunatelly, for RAID levels with redundancy
unmapped blocks will be mapped back during first rebuild/resync process.
Sponsored by: iXsystems, Inc.
MFC after: 1 month
provider name to be specified instead of geom name (first argument in all
subcommands except label). In most cases there is only one array used
any way, so it is not really useful to make user type ugly geom names like
Intel-f0bdf223 or SiI-732c2b9448cf. Though they can be used in some cases.
Sponsored by: iXsystems, Inc.
MFC after: 1 month
defined by the SNIA Common RAID Disk Data Format Specification v2.0.
Supports multiple volumes per array and multiple partitions per disk.
Supports standard big-endian and Adaptec's little-endian byte ordering.
Supports all single-layer RAID levels. Dual-layer RAID levels except
RAID10 are not supported now because of GEOM RAID design limitations.
Some work is still to be done, but the present code already manages basic
interoperation with RAID BIOS of the Adaptec 1430SA SATA RAID controller.
MFC after: 1 month
Sponsored by: iXsystems, Inc.
