diff --git a/MAINTAINERS b/MAINTAINERS index cb8f3ea2c2..684142e12e 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1881,6 +1881,7 @@ virtio-9p M: Greg Kurz M: Christian Schoenebeck S: Odd Fixes +W: https://wiki.qemu.org/Documentation/9p F: hw/9pfs/ X: hw/9pfs/xen-9p* F: fsdev/ diff --git a/hw/9pfs/9p-local.c b/hw/9pfs/9p-local.c index af52c1daac..210d9e7705 100644 --- a/hw/9pfs/9p-local.c +++ b/hw/9pfs/9p-local.c @@ -10,6 +10,11 @@ * the COPYING file in the top-level directory. */ +/* + * Not so fast! You might want to read the 9p developer docs first: + * https://wiki.qemu.org/Documentation/9p + */ + #include "qemu/osdep.h" #include "9p.h" #include "9p-local.h" diff --git a/hw/9pfs/9p-posix-acl.c b/hw/9pfs/9p-posix-acl.c index bbf89064f7..eadae270dd 100644 --- a/hw/9pfs/9p-posix-acl.c +++ b/hw/9pfs/9p-posix-acl.c @@ -11,6 +11,11 @@ * */ +/* + * Not so fast! You might want to read the 9p developer docs first: + * https://wiki.qemu.org/Documentation/9p + */ + #include "qemu/osdep.h" #include "qemu/xattr.h" #include "9p.h" diff --git a/hw/9pfs/9p-proxy.c b/hw/9pfs/9p-proxy.c index 4aa4e0a3ba..09bd9f1464 100644 --- a/hw/9pfs/9p-proxy.c +++ b/hw/9pfs/9p-proxy.c @@ -10,6 +10,11 @@ * the COPYING file in the top-level directory. */ +/* + * Not so fast! You might want to read the 9p developer docs first: + * https://wiki.qemu.org/Documentation/9p + */ + #include "qemu/osdep.h" #include #include diff --git a/hw/9pfs/9p-synth.c b/hw/9pfs/9p-synth.c index 473ef914b0..b38088e066 100644 --- a/hw/9pfs/9p-synth.c +++ b/hw/9pfs/9p-synth.c @@ -12,6 +12,11 @@ * */ +/* + * Not so fast! You might want to read the 9p developer docs first: + * https://wiki.qemu.org/Documentation/9p + */ + #include "qemu/osdep.h" #include "9p.h" #include "fsdev/qemu-fsdev.h" diff --git a/hw/9pfs/9p-util.c b/hw/9pfs/9p-util.c index 614b7fc34d..3221d9b498 100644 --- a/hw/9pfs/9p-util.c +++ b/hw/9pfs/9p-util.c @@ -10,6 +10,11 @@ * See the COPYING file in the top-level directory. */ +/* + * Not so fast! You might want to read the 9p developer docs first: + * https://wiki.qemu.org/Documentation/9p + */ + #include "qemu/osdep.h" #include "qemu/xattr.h" #include "9p-util.h" diff --git a/hw/9pfs/9p-xattr-user.c b/hw/9pfs/9p-xattr-user.c index 2c90817b75..f2ae9582e6 100644 --- a/hw/9pfs/9p-xattr-user.c +++ b/hw/9pfs/9p-xattr-user.c @@ -11,6 +11,11 @@ * */ +/* + * Not so fast! You might want to read the 9p developer docs first: + * https://wiki.qemu.org/Documentation/9p + */ + #include "qemu/osdep.h" #include "9p.h" #include "fsdev/file-op-9p.h" diff --git a/hw/9pfs/9p-xattr.c b/hw/9pfs/9p-xattr.c index c696d8f846..9ae69dd8db 100644 --- a/hw/9pfs/9p-xattr.c +++ b/hw/9pfs/9p-xattr.c @@ -11,6 +11,11 @@ * */ +/* + * Not so fast! You might want to read the 9p developer docs first: + * https://wiki.qemu.org/Documentation/9p + */ + #include "qemu/osdep.h" #include "9p.h" #include "fsdev/file-op-9p.h" diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c index 134806db52..2815257f42 100644 --- a/hw/9pfs/9p.c +++ b/hw/9pfs/9p.c @@ -11,6 +11,11 @@ * */ +/* + * Not so fast! You might want to read the 9p developer docs first: + * https://wiki.qemu.org/Documentation/9p + */ + #include "qemu/osdep.h" #include #include "hw/virtio/virtio.h" @@ -966,23 +971,6 @@ static int stat_to_qid(V9fsPDU *pdu, const struct stat *stbuf, V9fsQID *qidp) return 0; } -static int coroutine_fn fid_to_qid(V9fsPDU *pdu, V9fsFidState *fidp, - V9fsQID *qidp) -{ - struct stat stbuf; - int err; - - err = v9fs_co_lstat(pdu, &fidp->path, &stbuf); - if (err < 0) { - return err; - } - err = stat_to_qid(pdu, &stbuf, qidp); - if (err < 0) { - return err; - } - return 0; -} - V9fsPDU *pdu_alloc(V9fsState *s) { V9fsPDU *pdu = NULL; @@ -1395,6 +1383,7 @@ static void coroutine_fn v9fs_attach(void *opaque) size_t offset = 7; V9fsQID qid; ssize_t err; + struct stat stbuf; v9fs_string_init(&uname); v9fs_string_init(&aname); @@ -1417,7 +1406,13 @@ static void coroutine_fn v9fs_attach(void *opaque) clunk_fid(s, fid); goto out; } - err = fid_to_qid(pdu, fidp, &qid); + err = v9fs_co_lstat(pdu, &fidp->path, &stbuf); + if (err < 0) { + err = -EINVAL; + clunk_fid(s, fid); + goto out; + } + err = stat_to_qid(pdu, &stbuf, &qid); if (err < 0) { err = -EINVAL; clunk_fid(s, fid); @@ -1449,7 +1444,7 @@ static void coroutine_fn v9fs_attach(void *opaque) } err += offset; - memcpy(&s->root_qid, &qid, sizeof(qid)); + memcpy(&s->root_st, &stbuf, sizeof(stbuf)); trace_v9fs_attach_return(pdu->tag, pdu->id, qid.type, qid.version, qid.path); out: @@ -1700,12 +1695,9 @@ static bool name_is_illegal(const char *name) return !*name || strchr(name, '/') != NULL; } -static bool not_same_qid(const V9fsQID *qid1, const V9fsQID *qid2) +static bool same_stat_id(const struct stat *a, const struct stat *b) { - return - qid1->type != qid2->type || - qid1->version != qid2->version || - qid1->path != qid2->path; + return a->st_dev == b->st_dev && a->st_ino == b->st_ino; } static void coroutine_fn v9fs_walk(void *opaque) @@ -1713,9 +1705,9 @@ static void coroutine_fn v9fs_walk(void *opaque) int name_idx; V9fsQID *qids = NULL; int i, err = 0; - V9fsPath dpath, path; + V9fsPath dpath, path, *pathes = NULL; uint16_t nwnames; - struct stat stbuf; + struct stat stbuf, fidst, *stbufs = NULL; size_t offset = 7; int32_t fid, newfid; V9fsString *wnames = NULL; @@ -1734,9 +1726,15 @@ static void coroutine_fn v9fs_walk(void *opaque) trace_v9fs_walk(pdu->tag, pdu->id, fid, newfid, nwnames); - if (nwnames && nwnames <= P9_MAXWELEM) { + if (nwnames > P9_MAXWELEM) { + err = -EINVAL; + goto out_nofid; + } + if (nwnames) { wnames = g_new0(V9fsString, nwnames); qids = g_new0(V9fsQID, nwnames); + stbufs = g_new0(struct stat, nwnames); + pathes = g_new0(V9fsPath, nwnames); for (i = 0; i < nwnames; i++) { err = pdu_unmarshal(pdu, offset, "s", &wnames[i]); if (err < 0) { @@ -1748,9 +1746,6 @@ static void coroutine_fn v9fs_walk(void *opaque) } offset += err; } - } else if (nwnames > P9_MAXWELEM) { - err = -EINVAL; - goto out_nofid; } fidp = get_fid(pdu, fid); if (fidp == NULL) { @@ -1760,35 +1755,85 @@ static void coroutine_fn v9fs_walk(void *opaque) v9fs_path_init(&dpath); v9fs_path_init(&path); - - err = fid_to_qid(pdu, fidp, &qid); - if (err < 0) { - goto out; - } - /* - * Both dpath and path initially poin to fidp. + * Both dpath and path initially point to fidp. * Needed to handle request with nwnames == 0 */ v9fs_path_copy(&dpath, &fidp->path); v9fs_path_copy(&path, &fidp->path); - for (name_idx = 0; name_idx < nwnames; name_idx++) { - if (not_same_qid(&pdu->s->root_qid, &qid) || - strcmp("..", wnames[name_idx].data)) { - err = v9fs_co_name_to_path(pdu, &dpath, wnames[name_idx].data, - &path); - if (err < 0) { - goto out; - } - err = v9fs_co_lstat(pdu, &path, &stbuf); - if (err < 0) { - goto out; + /* + * To keep latency (i.e. overall execution time for processing this + * Twalk client request) as small as possible, run all the required fs + * driver code altogether inside the following block. + */ + v9fs_co_run_in_worker({ + if (v9fs_request_cancelled(pdu)) { + err = -EINTR; + break; + } + err = s->ops->lstat(&s->ctx, &dpath, &fidst); + if (err < 0) { + err = -errno; + break; + } + stbuf = fidst; + for (name_idx = 0; name_idx < nwnames; name_idx++) { + if (v9fs_request_cancelled(pdu)) { + err = -EINTR; + break; } + if (!same_stat_id(&pdu->s->root_st, &stbuf) || + strcmp("..", wnames[name_idx].data)) + { + err = s->ops->name_to_path(&s->ctx, &dpath, + wnames[name_idx].data, &path); + if (err < 0) { + err = -errno; + break; + } + if (v9fs_request_cancelled(pdu)) { + err = -EINTR; + break; + } + err = s->ops->lstat(&s->ctx, &path, &stbuf); + if (err < 0) { + err = -errno; + break; + } + stbufs[name_idx] = stbuf; + v9fs_path_copy(&dpath, &path); + v9fs_path_copy(&pathes[name_idx], &path); + } + } + }); + /* + * Handle all the rest of this Twalk request on main thread ... + */ + if (err < 0) { + goto out; + } + + err = stat_to_qid(pdu, &fidst, &qid); + if (err < 0) { + goto out; + } + stbuf = fidst; + + /* reset dpath and path */ + v9fs_path_copy(&dpath, &fidp->path); + v9fs_path_copy(&path, &fidp->path); + + for (name_idx = 0; name_idx < nwnames; name_idx++) { + if (!same_stat_id(&pdu->s->root_st, &stbuf) || + strcmp("..", wnames[name_idx].data)) + { + stbuf = stbufs[name_idx]; err = stat_to_qid(pdu, &stbuf, &qid); if (err < 0) { goto out; } + v9fs_path_copy(&path, &pathes[name_idx]); v9fs_path_copy(&dpath, &path); } memcpy(&qids[name_idx], &qid, sizeof(qid)); @@ -1824,9 +1869,12 @@ out_nofid: if (nwnames && nwnames <= P9_MAXWELEM) { for (name_idx = 0; name_idx < nwnames; name_idx++) { v9fs_string_free(&wnames[name_idx]); + v9fs_path_free(&pathes[name_idx]); } g_free(wnames); g_free(qids); + g_free(stbufs); + g_free(pathes); } } diff --git a/hw/9pfs/9p.h b/hw/9pfs/9p.h index 00381591ff..1567b67841 100644 --- a/hw/9pfs/9p.h +++ b/hw/9pfs/9p.h @@ -355,7 +355,7 @@ struct V9fsState { int32_t root_fid; Error *migration_blocker; V9fsConf fsconf; - V9fsQID root_qid; + struct stat root_st; dev_t dev_id; struct qht qpd_table; struct qht qpp_table; diff --git a/hw/9pfs/codir.c b/hw/9pfs/codir.c index 1f70a58df5..032cce04c4 100644 --- a/hw/9pfs/codir.c +++ b/hw/9pfs/codir.c @@ -11,6 +11,11 @@ * */ +/* + * Not so fast! You might want to read the 9p developer docs first: + * https://wiki.qemu.org/Documentation/9p + */ + #include "qemu/osdep.h" #include "fsdev/qemu-fsdev.h" #include "qemu/thread.h" diff --git a/hw/9pfs/cofile.c b/hw/9pfs/cofile.c index 83bb6c14e0..20f93a90e7 100644 --- a/hw/9pfs/cofile.c +++ b/hw/9pfs/cofile.c @@ -11,6 +11,11 @@ * */ +/* + * Not so fast! You might want to read the 9p developer docs first: + * https://wiki.qemu.org/Documentation/9p + */ + #include "qemu/osdep.h" #include "fsdev/qemu-fsdev.h" #include "qemu/thread.h" diff --git a/hw/9pfs/cofs.c b/hw/9pfs/cofs.c index 0b321b456e..9d0adc2e78 100644 --- a/hw/9pfs/cofs.c +++ b/hw/9pfs/cofs.c @@ -11,6 +11,11 @@ * */ +/* + * Not so fast! You might want to read the 9p developer docs first: + * https://wiki.qemu.org/Documentation/9p + */ + #include "qemu/osdep.h" #include "fsdev/qemu-fsdev.h" #include "qemu/thread.h" diff --git a/hw/9pfs/coth.c b/hw/9pfs/coth.c index 9778f24b00..2802d41cce 100644 --- a/hw/9pfs/coth.c +++ b/hw/9pfs/coth.c @@ -12,6 +12,11 @@ * */ +/* + * Not so fast! You might want to read the 9p developer docs first: + * https://wiki.qemu.org/Documentation/9p + */ + #include "qemu/osdep.h" #include "block/thread-pool.h" #include "qemu/coroutine.h" diff --git a/hw/9pfs/coxattr.c b/hw/9pfs/coxattr.c index 0e00ffaa0d..dbcd09e0fd 100644 --- a/hw/9pfs/coxattr.c +++ b/hw/9pfs/coxattr.c @@ -11,6 +11,11 @@ * */ +/* + * Not so fast! You might want to read the 9p developer docs first: + * https://wiki.qemu.org/Documentation/9p + */ + #include "qemu/osdep.h" #include "fsdev/qemu-fsdev.h" #include "qemu/thread.h" diff --git a/hw/9pfs/virtio-9p-device.c b/hw/9pfs/virtio-9p-device.c index 14371a78ef..54ee93b71f 100644 --- a/hw/9pfs/virtio-9p-device.c +++ b/hw/9pfs/virtio-9p-device.c @@ -11,6 +11,11 @@ * */ +/* + * Not so fast! You might want to read the 9p developer docs first: + * https://wiki.qemu.org/Documentation/9p + */ + #include "qemu/osdep.h" #include "hw/virtio/virtio.h" #include "qemu/sockets.h" diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c index a969fcc54c..65c4979c3c 100644 --- a/hw/9pfs/xen-9p-backend.c +++ b/hw/9pfs/xen-9p-backend.c @@ -8,6 +8,11 @@ * */ +/* + * Not so fast! You might want to read the 9p developer docs first: + * https://wiki.qemu.org/Documentation/9p + */ + #include "qemu/osdep.h" #include "hw/9pfs/9p.h" diff --git a/tests/qtest/libqos/virtio-9p.c b/tests/qtest/libqos/virtio-9p.c index be91662c6f..b4e1143288 100644 --- a/tests/qtest/libqos/virtio-9p.c +++ b/tests/qtest/libqos/virtio-9p.c @@ -16,6 +16,11 @@ * License along with this library; if not, see */ +/* + * Not so fast! You might want to read the 9p developer docs first: + * https://wiki.qemu.org/Documentation/9p + */ + #include "qemu/osdep.h" #include "libqtest.h" #include "qemu/module.h" diff --git a/tests/qtest/virtio-9p-test.c b/tests/qtest/virtio-9p-test.c index 92a498f249..41fed41de1 100644 --- a/tests/qtest/virtio-9p-test.c +++ b/tests/qtest/virtio-9p-test.c @@ -7,6 +7,11 @@ * See the COPYING file in the top-level directory. */ +/* + * Not so fast! You might want to read the 9p developer docs first: + * https://wiki.qemu.org/Documentation/9p + */ + #include "qemu/osdep.h" #include "libqtest-single.h" #include "qemu/module.h"