--- /dev/null
+/*
+ * QEMU Block driver for native access to files on NFS shares
+ *
+ * Copyright (c) 2014 Peter Lieven <pl@kamp.de>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "config-host.h"
+
+#include <poll.h>
+#include "qemu-common.h"
+#include "qemu/config-file.h"
+#include "qemu/error-report.h"
+#include "block/block_int.h"
+#include "trace.h"
+#include "qemu/iov.h"
+#include "qemu/uri.h"
+#include "sysemu/sysemu.h"
+#include <nfsc/libnfs.h>
+
+#define QEMU_NFS_MAX_READAHEAD_SIZE 1048576
+
+typedef struct NFSClient {
+ struct nfs_context *context;
+ struct nfsfh *fh;
+ int events;
+ bool has_zero_init;
+ AioContext *aio_context;
+} NFSClient;
+
+typedef struct NFSRPC {
+ int ret;
+ int complete;
+ QEMUIOVector *iov;
+ struct stat *st;
+ Coroutine *co;
+ QEMUBH *bh;
+ NFSClient *client;
+} NFSRPC;
+
+static void nfs_process_read(void *arg);
+static void nfs_process_write(void *arg);
+
+static void nfs_set_events(NFSClient *client)
+{
+ int ev = nfs_which_events(client->context);
+ if (ev != client->events) {
+ aio_set_fd_handler(client->aio_context,
+ nfs_get_fd(client->context),
+ (ev & POLLIN) ? nfs_process_read : NULL,
+ (ev & POLLOUT) ? nfs_process_write : NULL,
+ client);
+
+ }
+ client->events = ev;
+}
+
+static void nfs_process_read(void *arg)
+{
+ NFSClient *client = arg;
+ nfs_service(client->context, POLLIN);
+ nfs_set_events(client);
+}
+
+static void nfs_process_write(void *arg)
+{
+ NFSClient *client = arg;
+ nfs_service(client->context, POLLOUT);
+ nfs_set_events(client);
+}
+
+static void nfs_co_init_task(NFSClient *client, NFSRPC *task)
+{
+ *task = (NFSRPC) {
+ .co = qemu_coroutine_self(),
+ .client = client,
+ };
+}
+
+static void nfs_co_generic_bh_cb(void *opaque)
+{
+ NFSRPC *task = opaque;
+ task->complete = 1;
+ qemu_bh_delete(task->bh);
+ qemu_coroutine_enter(task->co, NULL);
+}
+
+static void
+nfs_co_generic_cb(int ret, struct nfs_context *nfs, void *data,
+ void *private_data)
+{
+ NFSRPC *task = private_data;
+ task->ret = ret;
+ if (task->ret > 0 && task->iov) {
+ if (task->ret <= task->iov->size) {
+ qemu_iovec_from_buf(task->iov, 0, data, task->ret);
+ } else {
+ task->ret = -EIO;
+ }
+ }
+ if (task->ret == 0 && task->st) {
+ memcpy(task->st, data, sizeof(struct stat));
+ }
+ if (task->ret < 0) {
+ error_report("NFS Error: %s", nfs_get_error(nfs));
+ }
+ if (task->co) {
+ task->bh = aio_bh_new(task->client->aio_context,
+ nfs_co_generic_bh_cb, task);
+ qemu_bh_schedule(task->bh);
+ } else {
+ task->complete = 1;
+ }
+}
+
+static int coroutine_fn nfs_co_readv(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors,
+ QEMUIOVector *iov)
+{
+ NFSClient *client = bs->opaque;
+ NFSRPC task;
+
+ nfs_co_init_task(client, &task);
+ task.iov = iov;
+
+ if (nfs_pread_async(client->context, client->fh,
+ sector_num * BDRV_SECTOR_SIZE,
+ nb_sectors * BDRV_SECTOR_SIZE,
+ nfs_co_generic_cb, &task) != 0) {
+ return -ENOMEM;
+ }
+
+ while (!task.complete) {
+ nfs_set_events(client);
+ qemu_coroutine_yield();
+ }
+
+ if (task.ret < 0) {
+ return task.ret;
+ }
+
+ /* zero pad short reads */
+ if (task.ret < iov->size) {
+ qemu_iovec_memset(iov, task.ret, 0, iov->size - task.ret);
+ }
+
+ return 0;
+}
+
+static int coroutine_fn nfs_co_writev(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors,
+ QEMUIOVector *iov)
+{
+ NFSClient *client = bs->opaque;
+ NFSRPC task;
+ char *buf = NULL;
+
+ nfs_co_init_task(client, &task);
+
+ buf = g_try_malloc(nb_sectors * BDRV_SECTOR_SIZE);
+ if (nb_sectors && buf == NULL) {
+ return -ENOMEM;
+ }
+
+ qemu_iovec_to_buf(iov, 0, buf, nb_sectors * BDRV_SECTOR_SIZE);
+
+ if (nfs_pwrite_async(client->context, client->fh,
+ sector_num * BDRV_SECTOR_SIZE,
+ nb_sectors * BDRV_SECTOR_SIZE,
+ buf, nfs_co_generic_cb, &task) != 0) {
+ g_free(buf);
+ return -ENOMEM;
+ }
+
+ while (!task.complete) {
+ nfs_set_events(client);
+ qemu_coroutine_yield();
+ }
+
+ g_free(buf);
+
+ if (task.ret != nb_sectors * BDRV_SECTOR_SIZE) {
+ return task.ret < 0 ? task.ret : -EIO;
+ }
+
+ return 0;
+}
+
+static int coroutine_fn nfs_co_flush(BlockDriverState *bs)
+{
+ NFSClient *client = bs->opaque;
+ NFSRPC task;
+
+ nfs_co_init_task(client, &task);
+
+ if (nfs_fsync_async(client->context, client->fh, nfs_co_generic_cb,
+ &task) != 0) {
+ return -ENOMEM;
+ }
+
+ while (!task.complete) {
+ nfs_set_events(client);
+ qemu_coroutine_yield();
+ }
+
+ return task.ret;
+}
+
+/* TODO Convert to fine grained options */
+static QemuOptsList runtime_opts = {
+ .name = "nfs",
+ .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
+ .desc = {
+ {
+ .name = "filename",
+ .type = QEMU_OPT_STRING,
+ .help = "URL to the NFS file",
+ },
+ { /* end of list */ }
+ },
+};
+
+static void nfs_detach_aio_context(BlockDriverState *bs)
+{
+ NFSClient *client = bs->opaque;
+
+ aio_set_fd_handler(client->aio_context,
+ nfs_get_fd(client->context),
+ NULL, NULL, NULL);
+ client->events = 0;
+}
+
+static void nfs_attach_aio_context(BlockDriverState *bs,
+ AioContext *new_context)
+{
+ NFSClient *client = bs->opaque;
+
+ client->aio_context = new_context;
+ nfs_set_events(client);
+}
+
+static void nfs_client_close(NFSClient *client)
+{
+ if (client->context) {
+ if (client->fh) {
+ nfs_close(client->context, client->fh);
+ }
+ aio_set_fd_handler(client->aio_context,
+ nfs_get_fd(client->context),
+ NULL, NULL, NULL);
+ nfs_destroy_context(client->context);
+ }
+ memset(client, 0, sizeof(NFSClient));
+}
+
+static void nfs_file_close(BlockDriverState *bs)
+{
+ NFSClient *client = bs->opaque;
+ nfs_client_close(client);
+}
+
+static int64_t nfs_client_open(NFSClient *client, const char *filename,
+ int flags, Error **errp)
+{
+ int ret = -EINVAL, i;
+ struct stat st;
+ URI *uri;
+ QueryParams *qp = NULL;
+ char *file = NULL, *strp = NULL;
+
+ uri = uri_parse(filename);
+ if (!uri) {
+ error_setg(errp, "Invalid URL specified");
+ goto fail;
+ }
+ if (!uri->server) {
+ error_setg(errp, "Invalid URL specified");
+ goto fail;
+ }
+ strp = strrchr(uri->path, '/');
+ if (strp == NULL) {
+ error_setg(errp, "Invalid URL specified");
+ goto fail;
+ }
+ file = g_strdup(strp);
+ *strp = 0;
+
+ client->context = nfs_init_context();
+ if (client->context == NULL) {
+ error_setg(errp, "Failed to init NFS context");
+ goto fail;
+ }
+
+ qp = query_params_parse(uri->query);
+ for (i = 0; i < qp->n; i++) {
+ unsigned long long val;
+ if (!qp->p[i].value) {
+ error_setg(errp, "Value for NFS parameter expected: %s",
+ qp->p[i].name);
+ goto fail;
+ }
+ if (parse_uint_full(qp->p[i].value, &val, 0)) {
+ error_setg(errp, "Illegal value for NFS parameter: %s",
+ qp->p[i].name);
+ goto fail;
+ }
+ if (!strcmp(qp->p[i].name, "uid")) {
+ nfs_set_uid(client->context, val);
+ } else if (!strcmp(qp->p[i].name, "gid")) {
+ nfs_set_gid(client->context, val);
+ } else if (!strcmp(qp->p[i].name, "tcp-syncnt")) {
+ nfs_set_tcp_syncnt(client->context, val);
+#ifdef LIBNFS_FEATURE_READAHEAD
+ } else if (!strcmp(qp->p[i].name, "readahead")) {
+ if (val > QEMU_NFS_MAX_READAHEAD_SIZE) {
+ error_report("NFS Warning: Truncating NFS readahead"
+ " size to %d", QEMU_NFS_MAX_READAHEAD_SIZE);
+ val = QEMU_NFS_MAX_READAHEAD_SIZE;
+ }
+ nfs_set_readahead(client->context, val);
+#endif
+ } else {
+ error_setg(errp, "Unknown NFS parameter name: %s",
+ qp->p[i].name);
+ goto fail;
+ }
+ }
+
+ ret = nfs_mount(client->context, uri->server, uri->path);
+ if (ret < 0) {
+ error_setg(errp, "Failed to mount nfs share: %s",
+ nfs_get_error(client->context));
+ goto fail;
+ }
+
+ if (flags & O_CREAT) {
+ ret = nfs_creat(client->context, file, 0600, &client->fh);
+ if (ret < 0) {
+ error_setg(errp, "Failed to create file: %s",
+ nfs_get_error(client->context));
+ goto fail;
+ }
+ } else {
+ ret = nfs_open(client->context, file, flags, &client->fh);
+ if (ret < 0) {
+ error_setg(errp, "Failed to open file : %s",
+ nfs_get_error(client->context));
+ goto fail;
+ }
+ }
+
+ ret = nfs_fstat(client->context, client->fh, &st);
+ if (ret < 0) {
+ error_setg(errp, "Failed to fstat file: %s",
+ nfs_get_error(client->context));
+ goto fail;
+ }
+
+ ret = DIV_ROUND_UP(st.st_size, BDRV_SECTOR_SIZE);
+ client->has_zero_init = S_ISREG(st.st_mode);
+ goto out;
+fail:
+ nfs_client_close(client);
+out:
+ if (qp) {
+ query_params_free(qp);
+ }
+ uri_free(uri);
+ g_free(file);
+ return ret;
+}
+
+static int nfs_file_open(BlockDriverState *bs, QDict *options, int flags,
+ Error **errp) {
+ NFSClient *client = bs->opaque;
+ int64_t ret;
+ QemuOpts *opts;
+ Error *local_err = NULL;
+
+ client->aio_context = bdrv_get_aio_context(bs);
+
+ opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
+ qemu_opts_absorb_qdict(opts, options, &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
+ ret = -EINVAL;
+ goto out;
+ }
+ ret = nfs_client_open(client, qemu_opt_get(opts, "filename"),
+ (flags & BDRV_O_RDWR) ? O_RDWR : O_RDONLY,
+ errp);
+ if (ret < 0) {
+ goto out;
+ }
+ bs->total_sectors = ret;
+ ret = 0;
+out:
+ qemu_opts_del(opts);
+ return ret;
+}
+
+static QemuOptsList nfs_create_opts = {
+ .name = "nfs-create-opts",
+ .head = QTAILQ_HEAD_INITIALIZER(nfs_create_opts.head),
+ .desc = {
+ {
+ .name = BLOCK_OPT_SIZE,
+ .type = QEMU_OPT_SIZE,
+ .help = "Virtual disk size"
+ },
+ { /* end of list */ }
+ }
+};
+
+static int nfs_file_create(const char *url, QemuOpts *opts, Error **errp)
+{
+ int ret = 0;
+ int64_t total_size = 0;
+ NFSClient *client = g_new0(NFSClient, 1);
+
+ client->aio_context = qemu_get_aio_context();
+
+ /* Read out options */
+ total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
+ BDRV_SECTOR_SIZE);
+
+ ret = nfs_client_open(client, url, O_CREAT, errp);
+ if (ret < 0) {
+ goto out;
+ }
+ ret = nfs_ftruncate(client->context, client->fh, total_size);
+ nfs_client_close(client);
+out:
+ g_free(client);
+ return ret;
+}
+
+static int nfs_has_zero_init(BlockDriverState *bs)
+{
+ NFSClient *client = bs->opaque;
+ return client->has_zero_init;
+}
+
+static int64_t nfs_get_allocated_file_size(BlockDriverState *bs)
+{
+ NFSClient *client = bs->opaque;
+ NFSRPC task = {0};
+ struct stat st;
+
+ task.st = &st;
+ if (nfs_fstat_async(client->context, client->fh, nfs_co_generic_cb,
+ &task) != 0) {
+ return -ENOMEM;
+ }
+
+ while (!task.complete) {
+ nfs_set_events(client);
+ aio_poll(client->aio_context, true);
+ }
+
+ return (task.ret < 0 ? task.ret : st.st_blocks * st.st_blksize);
+}
+
+static int nfs_file_truncate(BlockDriverState *bs, int64_t offset)
+{
+ NFSClient *client = bs->opaque;
+ return nfs_ftruncate(client->context, client->fh, offset);
+}
+
+static BlockDriver bdrv_nfs = {
+ .format_name = "nfs",
+ .protocol_name = "nfs",
+
+ .instance_size = sizeof(NFSClient),
+ .bdrv_needs_filename = true,
+ .create_opts = &nfs_create_opts,
+
+ .bdrv_has_zero_init = nfs_has_zero_init,
+ .bdrv_get_allocated_file_size = nfs_get_allocated_file_size,
+ .bdrv_truncate = nfs_file_truncate,
+
+ .bdrv_file_open = nfs_file_open,
+ .bdrv_close = nfs_file_close,
+ .bdrv_create = nfs_file_create,
+
+ .bdrv_co_readv = nfs_co_readv,
+ .bdrv_co_writev = nfs_co_writev,
+ .bdrv_co_flush_to_disk = nfs_co_flush,
+
+ .bdrv_detach_aio_context = nfs_detach_aio_context,
+ .bdrv_attach_aio_context = nfs_attach_aio_context,
+};
+
+static void nfs_block_init(void)
+{
+ bdrv_register(&bdrv_nfs);
+}
+
+block_init(nfs_block_init);
Code Review / kvmfornfv.git / blobdiff