From d3ab98e6919e9491f8ed7ffe37af73d35a55e1ca Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Wed, 12 Oct 2011 19:11:23 +0530 Subject: hw/9pfs: Add new virtfs option writeout=immediate skip host page cache writeout=immediate implies the after pwritev we do a sync_file_range. Reviewed-by: Stefan Hajnoczi Signed-off-by: Aneesh Kumar K.V --- fsdev/file-op-9p.h | 4 ++++ fsdev/qemu-fsdev.c | 10 ++++++++-- fsdev/qemu-fsdev.h | 1 + hw/9pfs/virtio-9p-device.c | 1 + hw/9pfs/virtio-9p-handle.c | 17 +++++++++++++++-- hw/9pfs/virtio-9p-local.c | 18 ++++++++++++++++-- hw/9pfs/virtio-9p.c | 22 ++++++++++++++++------ qemu-config.c | 6 ++++++ qemu-options.hx | 17 ++++++++++++----- vl.c | 12 ++++++++++++ 10 files changed, 91 insertions(+), 17 deletions(-) diff --git a/fsdev/file-op-9p.h b/fsdev/file-op-9p.h index 8de8abfd5b..af3ecbecb7 100644 --- a/fsdev/file-op-9p.h +++ b/fsdev/file-op-9p.h @@ -53,12 +53,16 @@ struct xattr_operations; /* FsContext flag values */ #define PATHNAME_FSCONTEXT 0x1 +/* export flags */ +#define V9FS_IMMEDIATE_WRITEOUT 0x1 + typedef struct FsContext { int flags; char *fs_root; SecModel fs_sm; uid_t uid; + int export_flags; struct xattr_operations **xops; /* fs driver specific data */ void *private; diff --git a/fsdev/qemu-fsdev.c b/fsdev/qemu-fsdev.c index 768819f575..946bad7998 100644 --- a/fsdev/qemu-fsdev.c +++ b/fsdev/qemu-fsdev.c @@ -34,6 +34,8 @@ int qemu_fsdev_add(QemuOpts *opts) const char *fstype = qemu_opt_get(opts, "fstype"); const char *path = qemu_opt_get(opts, "path"); const char *sec_model = qemu_opt_get(opts, "security_model"); + const char *writeout = qemu_opt_get(opts, "writeout"); + if (!fsdev_id) { fprintf(stderr, "fsdev: No id specified\n"); @@ -72,10 +74,14 @@ int qemu_fsdev_add(QemuOpts *opts) fsle->fse.path = g_strdup(path); fsle->fse.security_model = g_strdup(sec_model); fsle->fse.ops = FsTypes[i].ops; - + fsle->fse.export_flags = 0; + if (writeout) { + if (!strcmp(writeout, "immediate")) { + fsle->fse.export_flags = V9FS_IMMEDIATE_WRITEOUT; + } + } QTAILQ_INSERT_TAIL(&fstype_entries, fsle, next); return 0; - } FsTypeEntry *get_fsdev_fsentry(char *id) diff --git a/fsdev/qemu-fsdev.h b/fsdev/qemu-fsdev.h index e04931a58d..3b2feb4643 100644 --- a/fsdev/qemu-fsdev.h +++ b/fsdev/qemu-fsdev.h @@ -41,6 +41,7 @@ typedef struct FsTypeEntry { char *fsdev_id; char *path; char *security_model; + int export_flags; FileOperations *ops; } FsTypeEntry; diff --git a/hw/9pfs/virtio-9p-device.c b/hw/9pfs/virtio-9p-device.c index e5b68dad5a..403eed089e 100644 --- a/hw/9pfs/virtio-9p-device.c +++ b/hw/9pfs/virtio-9p-device.c @@ -115,6 +115,7 @@ VirtIODevice *virtio_9p_init(DeviceState *dev, V9fsConf *conf) exit(1); } + s->ctx.export_flags = fse->export_flags; s->ctx.fs_root = g_strdup(fse->path); len = strlen(conf->tag); if (len > MAX_TAG_LEN) { diff --git a/hw/9pfs/virtio-9p-handle.c b/hw/9pfs/virtio-9p-handle.c index 5c8b5ed471..b248e44916 100644 --- a/hw/9pfs/virtio-9p-handle.c +++ b/hw/9pfs/virtio-9p-handle.c @@ -192,16 +192,29 @@ static ssize_t handle_preadv(FsContext *ctx, int fd, const struct iovec *iov, static ssize_t handle_pwritev(FsContext *ctx, int fd, const struct iovec *iov, int iovcnt, off_t offset) { + ssize_t ret; #ifdef CONFIG_PREADV - return pwritev(fd, iov, iovcnt, offset); + ret = pwritev(fd, iov, iovcnt, offset); #else int err = lseek(fd, offset, SEEK_SET); if (err == -1) { return err; } else { - return writev(fd, iov, iovcnt); + ret = writev(fd, iov, iovcnt); } #endif +#ifdef CONFIG_SYNC_FILE_RANGE + if (ret > 0 && ctx->export_flags & V9FS_IMMEDIATE_WRITEOUT) { + /* + * Initiate a writeback. This is not a data integrity sync. + * We want to ensure that we don't leave dirty pages in the cache + * after write when writeout=immediate is sepcified. + */ + sync_file_range(fd, offset, ret, + SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE); + } +#endif + return ret; } static int handle_chmod(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp) diff --git a/hw/9pfs/virtio-9p-local.c b/hw/9pfs/virtio-9p-local.c index 9559ff6550..47295b7e27 100644 --- a/hw/9pfs/virtio-9p-local.c +++ b/hw/9pfs/virtio-9p-local.c @@ -203,16 +203,30 @@ static ssize_t local_preadv(FsContext *ctx, int fd, const struct iovec *iov, static ssize_t local_pwritev(FsContext *ctx, int fd, const struct iovec *iov, int iovcnt, off_t offset) { + ssize_t ret +; #ifdef CONFIG_PREADV - return pwritev(fd, iov, iovcnt, offset); + ret = pwritev(fd, iov, iovcnt, offset); #else int err = lseek(fd, offset, SEEK_SET); if (err == -1) { return err; } else { - return writev(fd, iov, iovcnt); + ret = writev(fd, iov, iovcnt); } #endif +#ifdef CONFIG_SYNC_FILE_RANGE + if (ret > 0 && ctx->export_flags & V9FS_IMMEDIATE_WRITEOUT) { + /* + * Initiate a writeback. This is not a data integrity sync. + * We want to ensure that we don't leave dirty pages in the cache + * after write when writeout=immediate is sepcified. + */ + sync_file_range(fd, offset, ret, + SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE); + } +#endif + return ret; } static int local_chmod(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp) diff --git a/hw/9pfs/virtio-9p.c b/hw/9pfs/virtio-9p.c index c01c31aa25..3958788248 100644 --- a/hw/9pfs/virtio-9p.c +++ b/hw/9pfs/virtio-9p.c @@ -80,6 +80,20 @@ void cred_init(FsCred *credp) credp->fc_rdev = -1; } +static int get_dotl_openflags(V9fsState *s, int oflags) +{ + int flags; + /* + * Filter the client open flags + */ + flags = oflags & ~(O_NOCTTY | O_ASYNC | O_CREAT); + /* + * Ignore direct disk access hint until the server supports it. + */ + flags &= ~O_DIRECT; + return flags; +} + void v9fs_string_init(V9fsString *str) { str->data = NULL; @@ -1598,10 +1612,7 @@ static void v9fs_open(void *opaque) err = offset; } else { if (s->proto_version == V9FS_PROTO_2000L) { - flags = mode; - flags &= ~(O_NOCTTY | O_ASYNC | O_CREAT); - /* Ignore direct disk access hint until the server supports it. */ - flags &= ~O_DIRECT; + flags = get_dotl_openflags(s, mode); } else { flags = omode_to_uflags(mode); } @@ -1650,8 +1661,7 @@ static void v9fs_lcreate(void *opaque) goto out_nofid; } - /* Ignore direct disk access hint until the server supports it. */ - flags &= ~O_DIRECT; + flags = get_dotl_openflags(pdu->s, flags); err = v9fs_co_open2(pdu, fidp, &name, gid, flags | O_CREAT, mode, &stbuf); if (err < 0) { diff --git a/qemu-config.c b/qemu-config.c index 7a7854fd06..4559236016 100644 --- a/qemu-config.c +++ b/qemu-config.c @@ -177,6 +177,9 @@ QemuOptsList qemu_fsdev_opts = { }, { .name = "security_model", .type = QEMU_OPT_STRING, + }, { + .name = "writeout", + .type = QEMU_OPT_STRING, }, { /*End of list */ } }, @@ -199,6 +202,9 @@ QemuOptsList qemu_virtfs_opts = { }, { .name = "security_model", .type = QEMU_OPT_STRING, + }, { + .name = "writeout", + .type = QEMU_OPT_STRING, }, { /*End of list */ } diff --git a/qemu-options.hx b/qemu-options.hx index dfbabd0088..20fd7b506f 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -525,7 +525,8 @@ ETEXI DEFHEADING(File system options:) DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev, - "-fsdev local,id=id,path=path,security_model=[mapped|passthrough|none]\n", + "-fsdev local,id=id,path=path,security_model=[mapped|passthrough|none]\n" + " [,writeout=immediate]\n", QEMU_ARCH_ALL) STEXI @@ -541,7 +542,7 @@ The specific Fstype will determine the applicable options. Options to each backend are described below. -@item -fsdev local ,id=@var{id} ,path=@var{path} ,security_model=@var{security_model} +@item -fsdev local ,id=@var{id} ,path=@var{path} ,security_model=@var{security_model}[,writeout=@var{writeout}] Create a file-system-"device" for local-filesystem. @@ -552,13 +553,17 @@ Create a file-system-"device" for local-filesystem. @option{security_model} specifies the security model to be followed. @option{security_model} is required. +@option{writeout} specifies whether to skip the host page cache. +@option{writeout} is an optional argument. + @end table ETEXI DEFHEADING(Virtual File system pass-through options:) DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs, - "-virtfs local,path=path,mount_tag=tag,security_model=[mapped|passthrough|none]\n", + "-virtfs local,path=path,mount_tag=tag,security_model=[mapped|passthrough|none]\n" + " [,writeout=immediate]\n", QEMU_ARCH_ALL) STEXI @@ -574,7 +579,7 @@ The specific Fstype will determine the applicable options. Options to each backend are described below. -@item -virtfs local ,path=@var{path} ,mount_tag=@var{mount_tag} ,security_model=@var{security_model} +@item -virtfs local ,path=@var{path} ,mount_tag=@var{mount_tag} ,security_model=@var{security_model}[,writeout=@var{writeout}] Create a Virtual file-system-pass through for local-filesystem. @@ -585,10 +590,12 @@ Create a Virtual file-system-pass through for local-filesystem. @option{security_model} specifies the security model to be followed. @option{security_model} is required. - @option{mount_tag} specifies the tag with which the exported file is mounted. @option{mount_tag} is required. +@option{writeout} specifies whether to skip the host page cache. +@option{writeout} is an optional argument. + @end table ETEXI diff --git a/vl.c b/vl.c index dbf77781a7..b3c27f6660 100644 --- a/vl.c +++ b/vl.c @@ -2785,6 +2785,7 @@ int main(int argc, char **argv, char **envp) case QEMU_OPTION_virtfs: { QemuOpts *fsdev; QemuOpts *device; + const char *writeout; olist = qemu_find_opts("virtfs"); if (!olist) { @@ -2814,6 +2815,17 @@ int main(int argc, char **argv, char **envp) qemu_opt_get(opts, "mount_tag")); exit(1); } + + writeout = qemu_opt_get(opts, "writeout"); + if (writeout) { +#ifdef CONFIG_SYNC_FILE_RANGE + qemu_opt_set(fsdev, "writeout", writeout); +#else + fprintf(stderr, "writeout=immediate not supported on " + "this platform\n"); + exit(1); +#endif + } qemu_opt_set(fsdev, "fstype", qemu_opt_get(opts, "fstype")); qemu_opt_set(fsdev, "path", qemu_opt_get(opts, "path")); qemu_opt_set(fsdev, "security_model", -- cgit v1.2.1