From 5e94c103a0321ca47deb81643839c44a03047416 Mon Sep 17 00:00:00 2001 From: "M. Mohan Kumar" Date: Wed, 9 Jun 2010 19:14:28 +0530 Subject: [PATCH] virtio-9p: Compute iounit based on host filesystem block size Compute iounit based on the host filesystem block size and pass it to client with open/create response. Also return iounit as statfs's f_bsize for optimal block size transfers. Signed-off-by: M. Mohan Kumar Reviewd-by: Sripathi Kodi Signed-off-by: Venkateswararao Jujjuri --- hw/virtio-9p.c | 96 ++++++++++++++++++++++++++++++++++++++++---------- hw/virtio-9p.h | 9 +++++ 2 files changed, 86 insertions(+), 19 deletions(-) diff --git a/hw/virtio-9p.c b/hw/virtio-9p.c index 78387b8193..f6eb0f3075 100644 --- a/hw/virtio-9p.c +++ b/hw/virtio-9p.c @@ -253,6 +253,11 @@ static int v9fs_do_fsync(V9fsState *s, int fd) return s->ops->fsync(&s->ctx, fd); } +static int v9fs_do_statfs(V9fsState *s, V9fsString *path, struct statfs *stbuf) +{ + return s->ops->statfs(&s->ctx, path->data, stbuf); +} + static void v9fs_string_init(V9fsString *str) { str->data = NULL; @@ -1019,11 +1024,10 @@ static void v9fs_fix_path(V9fsString *dst, V9fsString *src, int len) static void v9fs_version(V9fsState *s, V9fsPDU *pdu) { - int32_t msize; V9fsString version; size_t offset = 7; - pdu_unmarshal(pdu, offset, "ds", &msize, &version); + pdu_unmarshal(pdu, offset, "ds", &s->msize, &version); if (!strcmp(version.data, "9P2000.u")) { s->proto_version = V9FS_PROTO_2000U; @@ -1033,7 +1037,7 @@ static void v9fs_version(V9fsState *s, V9fsPDU *pdu) v9fs_string_sprintf(&version, "unknown"); } - offset += pdu_marshal(pdu, offset, "ds", msize, &version); + offset += pdu_marshal(pdu, offset, "ds", s->msize, &version); complete_pdu(s, pdu, offset); v9fs_string_free(&version); @@ -1288,6 +1292,26 @@ out: v9fs_walk_complete(s, vs, err); } +static int32_t get_iounit(V9fsState *s, V9fsString *name) +{ + struct statfs stbuf; + int32_t iounit = 0; + + /* + * iounit should be multiples of f_bsize (host filesystem block size + * and as well as less than (client msize - P9_IOHDRSZ)) + */ + if (!v9fs_do_statfs(s, name, &stbuf)) { + iounit = stbuf.f_bsize; + iounit *= (s->msize - P9_IOHDRSZ)/stbuf.f_bsize; + } + + if (!iounit) { + iounit = s->msize - P9_IOHDRSZ; + } + return iounit; +} + static void v9fs_open_post_opendir(V9fsState *s, V9fsOpenState *vs, int err) { if (vs->fidp->dir == NULL) { @@ -1303,6 +1327,15 @@ out: } +static void v9fs_open_post_getiounit(V9fsState *s, V9fsOpenState *vs) +{ + int err; + vs->offset += pdu_marshal(vs->pdu, vs->offset, "Qd", &vs->qid, vs->iounit); + err = vs->offset; + complete_pdu(s, vs->pdu, err); + qemu_free(vs); +} + static void v9fs_open_post_open(V9fsState *s, V9fsOpenState *vs, int err) { if (vs->fidp->fd == -1) { @@ -1310,8 +1343,9 @@ static void v9fs_open_post_open(V9fsState *s, V9fsOpenState *vs, int err) goto out; } - vs->offset += pdu_marshal(vs->pdu, vs->offset, "Qd", &vs->qid, 0); - err = vs->offset; + vs->iounit = get_iounit(s, &vs->fidp->path); + v9fs_open_post_getiounit(s, vs); + return; out: complete_pdu(s, vs->pdu, err); qemu_free(vs); @@ -1794,15 +1828,28 @@ out: qemu_free(vs); } -static void v9fs_post_create(V9fsState *s, V9fsCreateState *vs, int err) +static void v9fs_create_post_getiounit(V9fsState *s, V9fsCreateState *vs) { - if (err == 0) { - v9fs_string_copy(&vs->fidp->path, &vs->fullname); - stat_to_qid(&vs->stbuf, &vs->qid); + int err; + v9fs_string_copy(&vs->fidp->path, &vs->fullname); + stat_to_qid(&vs->stbuf, &vs->qid); - vs->offset += pdu_marshal(vs->pdu, vs->offset, "Qd", &vs->qid, 0); + vs->offset += pdu_marshal(vs->pdu, vs->offset, "Qd", &vs->qid, vs->iounit); + err = vs->offset; - err = vs->offset; + complete_pdu(s, vs->pdu, err); + v9fs_string_free(&vs->name); + v9fs_string_free(&vs->extension); + v9fs_string_free(&vs->fullname); + qemu_free(vs); +} + +static void v9fs_post_create(V9fsState *s, V9fsCreateState *vs, int err) +{ + if (err == 0) { + vs->iounit = get_iounit(s, &vs->fidp->path); + v9fs_create_post_getiounit(s, vs); + return; } complete_pdu(s, vs->pdu, err); @@ -2266,23 +2313,34 @@ out: qemu_free(vs); } -static int v9fs_do_statfs(V9fsState *s, V9fsString *path, struct statfs *stbuf) -{ - return s->ops->statfs(&s->ctx, path->data, stbuf); -} - static void v9fs_statfs_post_statfs(V9fsState *s, V9fsStatfsState *vs, int err) { + int32_t bsize_factor; + if (err) { err = -errno; goto out; } + /* + * compute bsize factor based on host file system block size + * and client msize + */ + bsize_factor = (s->msize - P9_IOHDRSZ)/vs->stbuf.f_bsize; + if (!bsize_factor) { + bsize_factor = 1; + } vs->v9statfs.f_type = vs->stbuf.f_type; vs->v9statfs.f_bsize = vs->stbuf.f_bsize; - vs->v9statfs.f_blocks = vs->stbuf.f_blocks; - vs->v9statfs.f_bfree = vs->stbuf.f_bfree; - vs->v9statfs.f_bavail = vs->stbuf.f_bavail; + vs->v9statfs.f_bsize *= bsize_factor; + /* + * f_bsize is adjusted(multiplied) by bsize factor, so we need to + * adjust(divide) the number of blocks, free blocks and available + * blocks by bsize factor + */ + vs->v9statfs.f_blocks = vs->stbuf.f_blocks/bsize_factor; + vs->v9statfs.f_bfree = vs->stbuf.f_bfree/bsize_factor; + vs->v9statfs.f_bavail = vs->stbuf.f_bavail/bsize_factor; vs->v9statfs.f_files = vs->stbuf.f_files; vs->v9statfs.f_ffree = vs->stbuf.f_ffree; vs->v9statfs.fsid_val = (unsigned int) vs->stbuf.f_fsid.__val[0] | diff --git a/hw/virtio-9p.h b/hw/virtio-9p.h index 9773659bb0..4ee38302b7 100644 --- a/hw/virtio-9p.h +++ b/hw/virtio-9p.h @@ -70,6 +70,12 @@ enum p9_proto_version { #define P9_NOFID (u32)(~0) #define P9_MAXWELEM 16 +/* + * ample room for Twrite/Rread header + * size[4] Tread/Twrite tag[2] fid[4] offset[8] count[4] + */ +#define P9_IOHDRSZ 24 + typedef struct V9fsPDU V9fsPDU; struct V9fsPDU @@ -154,6 +160,7 @@ typedef struct V9fsState uint8_t *tag; size_t config_size; enum p9_proto_version proto_version; + int32_t msize; } V9fsState; typedef struct V9fsCreateState { @@ -167,6 +174,7 @@ typedef struct V9fsCreateState { V9fsString name; V9fsString extension; V9fsString fullname; + int iounit; } V9fsCreateState; typedef struct V9fsStatState { @@ -197,6 +205,7 @@ typedef struct V9fsOpenState { V9fsFidState *fidp; V9fsQID qid; struct stat stbuf; + int iounit; } V9fsOpenState; typedef struct V9fsReadState { -- GitLab