From e97310b5583577612d81730cfaeb7a70d39039fe Mon Sep 17 00:00:00 2001
From: Taylor R Campbell <riastradh@NetBSD.org>
Date: Tue, 25 Feb 2020 00:40:05 +0000
Subject: [PATCH] New ioctl DIOCGSECTORALIGN returns sector alignment
parameters:
struct disk_sectoralign {
/* First aligned sector number. */
uint32_t dsa_firstaligned;
/* Number of sectors per aligned unit. */
uint32_t dsa_alignment;
};
- Teach wd(4) to get it from ATA.
- Teach cgd(4) to pass it through from the underlying disk.
- Teach dk(4) to pass it through with adjustments.
- Teach zpool to take advantage of it.
=> XXX zpool doesn't seem to understand when the vdev's starting
sector is misaligned.
---
.../osnet/dist/uts/common/fs/zfs/vdev_disk.c | 17 ++++++-
sys/dev/ata/wd.c | 47 ++++++++++++++++++-
sys/dev/ata/wdvar.h | 1 +
sys/dev/cgd.c | 27 +++++++++++
sys/dev/dkwedge/dk.c | 17 +++++++
sys/sys/disk.h | 6 +++
sys/sys/dkio.h | 3 ++
7 files changed, 116 insertions(+), 2 deletions(-)
diff --git a/external/cddl/osnet/dist/uts/common/fs/zfs/vdev_disk.c b/external/cddl/osnet/dist/uts/common/fs/zfs/vdev_disk.c
index 3a7e9d54c2a5..95000681486b 100644
--- a/external/cddl/osnet/dist/uts/common/fs/zfs/vdev_disk.c
+++ b/external/cddl/osnet/dist/uts/common/fs/zfs/vdev_disk.c
@@ -151,6 +151,7 @@ vdev_disk_open(vdev_t *vd, uint64_t *psize, uint64_t *max_psize,
unsigned secsize;
struct disk *pdk;
struct dkwedge_info dkw;
+ struct disk_sectoralign dsa;
/*
* We must have a pathname, and it must be absolute.
@@ -260,7 +261,21 @@ skip_open:
*max_psize = *psize;
*ashift = highbit(MAX(secsize, SPA_MINBLOCKSIZE)) - 1;
- *pashift = *ashift;
+
+ /*
+ * Try to determine whether the disk has a preferred physical
+ * sector size even if it can emulate a smaller logical sector
+ * size with r/m/w cycles, e.g. a disk with 4096-byte sectors
+ * that for compatibility claims to support 512-byte ones.
+ */
+ if (VOP_IOCTL(vp, DIOCGSECTORALIGN, &dsa, FREAD, NOCRED) == 0)
+ *pashift = highbit(dsa.dsa_alignment * secsize) - 1;
+ else
+ *pashift = *ashift;
+ if (dsa.dsa_firstaligned % dsa.dsa_alignment)
+ printf("ZFS WARNING: vdev %s: sectors are misaligned"
+ " (alignment=%"PRIu32", firstaligned=%"PRIu32")\n",
+ vd->vdev_path, dsa.dsa_alignment, dsa.dsa_firstaligned);
vd->vdev_wholedisk = 0;
if (getdiskinfo(vp, &dkw) != 0 &&
diff --git a/sys/dev/ata/wd.c b/sys/dev/ata/wd.c
index 039fd844c0d5..be12f307ac5f 100644
--- a/sys/dev/ata/wd.c
+++ b/sys/dev/ata/wd.c
@@ -430,16 +430,40 @@ wdattach(device_t parent, device_t self, void *aux)
} else {
wd->sc_blksize = 512;
}
+ wd->sc_sectoralign.dsa_firstaligned = 0;
+ wd->sc_sectoralign.dsa_alignment = 1;
+ if ((wd->sc_params.atap_secsz & ATA_SECSZ_VALID_MASK) == ATA_SECSZ_VALID
+ && ((wd->sc_params.atap_secsz & ATA_SECSZ_LPS) != 0)) {
+ wd->sc_sectoralign.dsa_alignment = 1 <<
+ (wd->sc_params.atap_secsz & ATA_SECSZ_LPS_SZMSK);
+ if ((wd->sc_params.atap_logical_align & ATA_LA_VALID_MASK) ==
+ ATA_LA_VALID) {
+ wd->sc_sectoralign.dsa_firstaligned =
+ (wd->sc_sectoralign.dsa_alignment -
+ (wd->sc_params.atap_logical_align &
+ ATA_LA_MASK));
+ }
+ }
wd->sc_capacity512 = (wd->sc_capacity * wd->sc_blksize) / DEV_BSIZE;
format_bytes(pbuf, sizeof(pbuf), wd->sc_capacity * wd->sc_blksize);
aprint_normal_dev(self, "%s, %d cyl, %d head, %d sec, "
- "%d bytes/sect x %llu sectors\n",
+ "%d bytes/sect x %llu sectors",
pbuf,
(wd->sc_flags & WDF_LBA) ? (int)(wd->sc_capacity /
(wd->sc_params.atap_heads * wd->sc_params.atap_sectors)) :
wd->sc_params.atap_cylinders,
wd->sc_params.atap_heads, wd->sc_params.atap_sectors,
wd->sc_blksize, (unsigned long long)wd->sc_capacity);
+ if (wd->sc_sectoralign.dsa_alignment != 1) {
+ aprint_normal(" (%d bytes/physsect",
+ wd->sc_sectoralign.dsa_alignment & wd->sc_blksize);
+ if (wd->sc_sectoralign.dsa_firstaligned != 0) {
+ aprint_normal("; first aligned sector: %jd",
+ (intmax_t)wd->sc_sectoralign.dsa_firstaligned);
+ }
+ aprint_normal(")");
+ }
+ aprint_normal("\n");
ATADEBUG_PRINT(("%s: atap_dmatiming_mimi=%d, atap_dmatiming_recom=%d\n",
device_xname(self), wd->sc_params.atap_dmatiming_mimi,
@@ -1409,6 +1433,27 @@ wdioctl(dev_t dev, u_long cmd, void *addr, int flag, struct lwp *l)
return(error1);
}
+ case DIOCGSECTORALIGN: {
+ struct disk_sectoralign *dsa = addr;
+ int part = WDPART(dev);
+
+ *dsa = wd->sc_sectoralign;
+ if (part != RAW_PART) {
+ struct disklabel *lp = dksc->sc_dkdev.dk_label;
+ daddr_t offset = lp->d_partitions[part].p_offset;
+ uint32_t r = offset % dsa->dsa_alignment;
+
+ if (r < dsa->dsa_firstaligned)
+ dsa->dsa_firstaligned = dsa->dsa_firstaligned
+ - r;
+ else
+ dsa->dsa_firstaligned = (dsa->dsa_firstaligned
+ + dsa->dsa_alignment) - r;
+ }
+
+ return 0;
+ }
+
default:
return dk_ioctl(dksc, dev, cmd, addr, flag, l);
}
diff --git a/sys/dev/ata/wdvar.h b/sys/dev/ata/wdvar.h
index 2f13ded15e38..461c08bdd023 100644
--- a/sys/dev/ata/wdvar.h
+++ b/sys/dev/ata/wdvar.h
@@ -59,6 +59,7 @@ struct wd_softc {
uint64_t sc_capacity512; /* ... in DEV_BSIZE blocks */
uint32_t sc_capacity28; /* capacity accessible with LBA28 commands */
uint32_t sc_blksize; /* logical block size, in bytes */
+ struct disk_sectoralign sc_sectoralign; /* sector alignment */
#ifdef WD_SOFTBADSECT
SLIST_HEAD(, disk_badsectors) sc_bslist;
diff --git a/sys/dev/cgd.c b/sys/dev/cgd.c
index 4c7348c364d0..46512e0bbbf0 100644
--- a/sys/dev/cgd.c
+++ b/sys/dev/cgd.c
@@ -722,6 +722,33 @@ cgdioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
* We pass this call down to the underlying disk.
*/
return VOP_IOCTL(cs->sc_tvn, cmd, data, flag, l->l_cred);
+ case DIOCGSECTORALIGN: {
+ struct disk_sectoralign *dsa = data;
+ int error;
+
+ if (!DK_ATTACHED(dksc))
+ return ENOENT;
+
+ /* Get the underlying disk's sector alignment. */
+ error = VOP_IOCTL(cs->sc_tvn, cmd, data, flag, l->l_cred);
+ if (error)
+ return error;
+
+ /* Adjust for the disklabel partition if necessary. */
+ if (part != RAW_PART) {
+ struct disklabel *lp = dksc->sc_dkdev.dk_label;
+ daddr_t offset = lp->d_partitions[part].p_offset;
+ uint32_t r = offset % dsa->dsa_alignment;
+
+ if (r < dsa->dsa_firstaligned)
+ dsa->dsa_firstaligned = dsa->dsa_firstaligned
+ - r;
+ else
+ dsa->dsa_firstaligned = (dsa->dsa_firstaligned
+ + dsa->dsa_alignment) - r;
+ }
+ return 0;
+ }
case DIOCGSTRATEGY:
case DIOCSSTRATEGY:
if (!DK_ATTACHED(dksc))
diff --git a/sys/dev/dkwedge/dk.c b/sys/dev/dkwedge/dk.c
index 30fc333d0b48..9492cf0d88ca 100644
--- a/sys/dev/dkwedge/dk.c
+++ b/sys/dev/dkwedge/dk.c
@@ -1501,7 +1501,24 @@ dkioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
break;
}
+ case DIOCGSECTORALIGN:
+ {
+ struct disk_sectoralign *dsa = data;
+ uint32_t r;
+
+ error = VOP_IOCTL(sc->sc_parent->dk_rawvp, cmd, dsa, flag,
+ l != NULL ? l->l_cred : NOCRED);
+ if (error)
+ break;
+ r = sc->sc_offset % dsa->dsa_alignment;
+ if (r < dsa->dsa_firstaligned)
+ dsa->dsa_firstaligned = dsa->dsa_firstaligned - r;
+ else
+ dsa->dsa_firstaligned = (dsa->dsa_firstaligned +
+ dsa->dsa_alignment) - r;
+ break;
+ }
default:
error = ENOTTY;
}
diff --git a/sys/sys/disk.h b/sys/sys/disk.h
index 100a44c3f880..ed25eb657017 100644
--- a/sys/sys/disk.h
+++ b/sys/sys/disk.h
@@ -300,6 +300,12 @@ struct disk_strategy {
size_t dks_paramlen; /* notyet; should be 0 */
};
+/* Sector alignment */
+struct disk_sectoralign {
+ uint32_t dsa_firstaligned; /* first aligned sector # */
+ uint32_t dsa_alignment; /* sectors per aligned sector */
+};
+
#ifdef _KERNEL
#include <sys/device.h>
#include <sys/mutex.h>
diff --git a/sys/sys/dkio.h b/sys/sys/dkio.h
index 84046268d0a4..937df511d791 100644
--- a/sys/sys/dkio.h
+++ b/sys/sys/dkio.h
@@ -133,4 +133,7 @@
/* mass removal */
#define DIOCRMWEDGES _IOR('d', 134, int) /* remove all wedges */
+ /* sector alignment */
+#define DIOCGSECTORALIGN _IOR('d', 135, struct disk_sectoralign)
+
#endif /* _SYS_DKIO_H_ */