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Add support for TOPOLOGY feature of virtio block device.

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Passing through physical block size/offset from underlying storage allows
guest to manage proper data and I/O alignment to improve performance.

MFC after:	2 weeks
This commit is contained in:
mav 2015-03-05 10:40:45 +00:00
parent a12775b872
commit 214386b6e7
1 changed files with 33 additions and 13 deletions
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46
usr.sbin/bhyve/pci_virtio_block.c
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@ -64,7 +64,8 @@ __FBSDID("$FreeBSD$");
/* Capability bits */
#define VTBLK_F_SEG_MAX (1 << 2) /* Maximum request segments */
#define VTBLK_F_BLK_SIZE (1 << 6) /* cfg block size valid */
#define VTBLK_F_BLK_SIZE (1 << 6) /* cfg block size valid */
#define VTBLK_F_TOPOLOGY (1 << 10) /* Optimal I/O alignment */
/*
* Host capabilities
@ -72,6 +73,7 @@ __FBSDID("$FreeBSD$");
#define VTBLK_S_HOSTCAPS \
( VTBLK_F_SEG_MAX | \
VTBLK_F_BLK_SIZE | \
VTBLK_F_TOPOLOGY | \
VIRTIO_RING_F_INDIRECT_DESC ) /* indirect descriptors */
/*
@ -81,11 +83,19 @@ struct vtblk_config {
uint64_t vbc_capacity;
uint32_t vbc_size_max;
uint32_t vbc_seg_max;
uint16_t vbc_geom_c;
uint8_t vbc_geom_h;
uint8_t vbc_geom_s;
struct {
uint16_t cylinders;
uint8_t heads;
uint8_t sectors;
} vbc_geometry;
uint32_t vbc_blk_size;
uint32_t vbc_sectors_max;
struct {
uint8_t physical_block_exp;
uint8_t alignment_offset;
uint16_t min_io_size;
uint32_t opt_io_size;
} vbc_topology;
uint8_t vbc_writeback;
} __packed;
/*
@ -262,7 +272,7 @@ pci_vtblk_init(struct vmctx *ctx, struct pci_devinst *pi, char *opts)
MD5_CTX mdctx;
u_char digest[16];
struct pci_vtblk_softc *sc;
off_t size;
off_t size, sts, sto;
int fd;
int sectsz;
@ -291,6 +301,7 @@ pci_vtblk_init(struct vmctx *ctx, struct pci_devinst *pi, char *opts)
*/
size = sbuf.st_size;
sectsz = DEV_BSIZE;
sts = sto = 0;
if (S_ISCHR(sbuf.st_mode)) {
if (ioctl(fd, DIOCGMEDIASIZE, &size) < 0 ||
ioctl(fd, DIOCGSECTORSIZE, &sectsz)) {
@ -300,7 +311,10 @@ pci_vtblk_init(struct vmctx *ctx, struct pci_devinst *pi, char *opts)
}
assert(size != 0);
assert(sectsz != 0);
}
if (ioctl(fd, DIOCGSTRIPESIZE, &sts) == 0)
ioctl(fd, DIOCGSTRIPEOFFSET, &sto);
} else
sts = sbuf.st_blksize;
sc = calloc(1, sizeof(struct pci_vtblk_softc));
@ -328,13 +342,19 @@ pci_vtblk_init(struct vmctx *ctx, struct pci_devinst *pi, char *opts)
/* setup virtio block config space */
sc->vbsc_cfg.vbc_capacity = size / DEV_BSIZE; /* 512-byte units */
sc->vbsc_cfg.vbc_seg_max = VTBLK_MAXSEGS;
sc->vbsc_cfg.vbc_blk_size = sectsz;
sc->vbsc_cfg.vbc_size_max = 0; /* not negotiated */
sc->vbsc_cfg.vbc_geom_c = 0; /* no geometry */
sc->vbsc_cfg.vbc_geom_h = 0;
sc->vbsc_cfg.vbc_geom_s = 0;
sc->vbsc_cfg.vbc_sectors_max = 0;
sc->vbsc_cfg.vbc_seg_max = VTBLK_MAXSEGS;
sc->vbsc_cfg.vbc_geometry.cylinders = 0; /* no geometry */
sc->vbsc_cfg.vbc_geometry.heads = 0;
sc->vbsc_cfg.vbc_geometry.sectors = 0;
sc->vbsc_cfg.vbc_blk_size = sectsz;
sc->vbsc_cfg.vbc_topology.physical_block_exp =
(sts > sectsz) ? (ffsll(sts / sectsz) - 1) : 0;
sc->vbsc_cfg.vbc_topology.alignment_offset =
(sto != 0) ? ((sts - sto) / sectsz) : 0;
sc->vbsc_cfg.vbc_topology.min_io_size = 0;
sc->vbsc_cfg.vbc_topology.opt_io_size = 0;
sc->vbsc_cfg.vbc_writeback = 0;
/*
* Should we move some of this into virtio.c? Could