From patchwork Wed Jul 1 16:29:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nastya Vicodin X-Patchwork-Id: 240632 List-Id: U-Boot discussion From: vicooodin at gmail.com (Anastasiia Lukianenko) Date: Wed, 1 Jul 2020 19:29:56 +0300 Subject: [PATCH 14/17] xen: pvblock: Read XenStore configuration and initialize In-Reply-To: <20200701162959.9814-1-vicooodin@gmail.com> References: <20200701162959.9814-1-vicooodin@gmail.com> Message-ID: <20200701162959.9814-15-vicooodin@gmail.com> From: Anastasiia Lukianenko Read essential virtual block device configuration data from XenStore, initialize front ring and event channel. Update block device description with actual block size. Use code for XenStore from mini-os. Signed-off-by: Oleksandr Andrushchenko Signed-off-by: Anastasiia Lukianenko --- drivers/xen/pvblock.c | 272 +++++++++++++++++++++++++++++++++++++++++- 1 file changed, 271 insertions(+), 1 deletion(-) diff --git a/drivers/xen/pvblock.c b/drivers/xen/pvblock.c index 6ce0ae97c3..9ed18be633 100644 --- a/drivers/xen/pvblock.c +++ b/drivers/xen/pvblock.c @@ -1,6 +1,7 @@ /* * SPDX-License-Identifier: GPL-2.0+ * + * (C) 2007-2008 Samuel Thibault. * (C) Copyright 2020 EPAM Systems Inc. */ #include @@ -10,26 +11,289 @@ #include #include +#include +#include +#include + +#include + +#include +#include +#include #include +#include +#include +#include + #define DRV_NAME "pvblock" #define DRV_NAME_BLK "pvblock_blk" +#define O_RDONLY 00 +#define O_RDWR 02 + +struct blkfront_info { + u64 sectors; + unsigned int sector_size; + int mode; + int info; + int barrier; + int flush; +}; + struct blkfront_dev { - char dummy; + domid_t dom; + + struct blkif_front_ring ring; + grant_ref_t ring_ref; + evtchn_port_t evtchn; + blkif_vdev_t handle; + + char *nodename; + char *backend; + struct blkfront_info info; + unsigned int devid; }; struct blkfront_platdata { unsigned int devid; }; +static void free_blkfront(struct blkfront_dev *dev) +{ + mask_evtchn(dev->evtchn); + free(dev->backend); + + gnttab_end_access(dev->ring_ref); + free(dev->ring.sring); + + unbind_evtchn(dev->evtchn); + + free(dev->nodename); + free(dev); +} + +static void blkfront_handler(evtchn_port_t port, struct pt_regs *regs, + void *data) +{ + printf("%s [Port %d] - event received\n", __func__, port); +} + static int init_blkfront(unsigned int devid, struct blkfront_dev *dev) { + xenbus_transaction_t xbt; + char *err = NULL; + char *message = NULL; + struct blkif_sring *s; + int retry = 0; + char *msg = NULL; + char *c; + char nodename[32]; + char path[ARRAY_SIZE(nodename) + strlen("/backend-id") + 1]; + + sprintf(nodename, "device/vbd/%d", devid); + + memset(dev, 0, sizeof(*dev)); + dev->nodename = strdup(nodename); + dev->devid = devid; + + snprintf(path, sizeof(path), "%s/backend-id", nodename); + dev->dom = xenbus_read_integer(path); + evtchn_alloc_unbound(dev->dom, blkfront_handler, dev, &dev->evtchn); + + s = (struct blkif_sring *)memalign(PAGE_SIZE, PAGE_SIZE); + if (!s) { + printf("Failed to allocate shared ring\n"); + goto error; + } + + SHARED_RING_INIT(s); + FRONT_RING_INIT(&dev->ring, s, PAGE_SIZE); + + dev->ring_ref = gnttab_grant_access(dev->dom, virt_to_pfn(s), 0); + +again: + err = xenbus_transaction_start(&xbt); + if (err) { + printf("starting transaction\n"); + free(err); + } + + err = xenbus_printf(xbt, nodename, "ring-ref", "%u", dev->ring_ref); + if (err) { + message = "writing ring-ref"; + goto abort_transaction; + } + err = xenbus_printf(xbt, nodename, "event-channel", "%u", dev->evtchn); + if (err) { + message = "writing event-channel"; + goto abort_transaction; + } + err = xenbus_printf(xbt, nodename, "protocol", "%s", + XEN_IO_PROTO_ABI_NATIVE); + if (err) { + message = "writing protocol"; + goto abort_transaction; + } + + snprintf(path, sizeof(path), "%s/state", nodename); + err = xenbus_switch_state(xbt, path, XenbusStateConnected); + if (err) { + message = "switching state"; + goto abort_transaction; + } + + err = xenbus_transaction_end(xbt, 0, &retry); + free(err); + if (retry) { + goto again; + printf("completing transaction\n"); + } + + goto done; + +abort_transaction: + free(err); + err = xenbus_transaction_end(xbt, 1, &retry); + printf("Abort transaction %s\n", message); + goto error; + +done: + snprintf(path, sizeof(path), "%s/backend", nodename); + msg = xenbus_read(XBT_NIL, path, &dev->backend); + if (msg) { + printf("Error %s when reading the backend path %s\n", + msg, path); + goto error; + } + + dev->handle = strtoul(strrchr(nodename, '/') + 1, NULL, 0); + + { + XenbusState state; + char path[strlen(dev->backend) + + strlen("/feature-flush-cache") + 1]; + + snprintf(path, sizeof(path), "%s/mode", dev->backend); + msg = xenbus_read(XBT_NIL, path, &c); + if (msg) { + printf("Error %s when reading the mode\n", msg); + goto error; + } + if (*c == 'w') + dev->info.mode = O_RDWR; + else + dev->info.mode = O_RDONLY; + free(c); + + snprintf(path, sizeof(path), "%s/state", dev->backend); + + msg = NULL; + state = xenbus_read_integer(path); + while (msg == NULL && state < XenbusStateConnected) + msg = xenbus_wait_for_state_change(path, &state); + if (msg != NULL || state != XenbusStateConnected) { + printf("backend not available, state=%d\n", state); + goto error; + } + + snprintf(path, sizeof(path), "%s/info", dev->backend); + dev->info.info = xenbus_read_integer(path); + + snprintf(path, sizeof(path), "%s/sectors", dev->backend); + /* + * FIXME: read_integer returns an int, so disk size + * limited to 1TB for now + */ + dev->info.sectors = xenbus_read_integer(path); + + snprintf(path, sizeof(path), "%s/sector-size", dev->backend); + dev->info.sector_size = xenbus_read_integer(path); + + snprintf(path, sizeof(path), "%s/feature-barrier", + dev->backend); + dev->info.barrier = xenbus_read_integer(path); + + snprintf(path, sizeof(path), "%s/feature-flush-cache", + dev->backend); + dev->info.flush = xenbus_read_integer(path); + } + unmask_evtchn(dev->evtchn); + + debug("%llu sectors of %u bytes\n", + dev->info.sectors, dev->info.sector_size); + return 0; + +error: + free(msg); + free(err); + free_blkfront(dev); + return -ENODEV; } static void shutdown_blkfront(struct blkfront_dev *dev) { + char *err = NULL, *err2; + XenbusState state; + + char path[strlen(dev->backend) + strlen("/state") + 1]; + char nodename[strlen(dev->nodename) + strlen("/event-channel") + 1]; + + debug("Close " DRV_NAME ", device ID %d\n", dev->devid); + + snprintf(path, sizeof(path), "%s/state", dev->backend); + snprintf(nodename, sizeof(nodename), "%s/state", dev->nodename); + + if ((err = xenbus_switch_state(XBT_NIL, nodename, + XenbusStateClosing)) != NULL) { + printf("%s: error changing state to %d: %s\n", __func__, + XenbusStateClosing, err); + goto close; + } + + state = xenbus_read_integer(path); + while (err == NULL && state < XenbusStateClosing) + err = xenbus_wait_for_state_change(path, &state); + free(err); + + if ((err = xenbus_switch_state(XBT_NIL, nodename, + XenbusStateClosed)) != NULL) { + printf("%s: error changing state to %d: %s\n", __func__, + XenbusStateClosed, err); + goto close; + } + + state = xenbus_read_integer(path); + while (state < XenbusStateClosed) { + err = xenbus_wait_for_state_change(path, &state); + free(err); + } + + if ((err = xenbus_switch_state(XBT_NIL, nodename, + XenbusStateInitialising)) != NULL) { + printf("%s: error changing state to %d: %s\n", __func__, + XenbusStateInitialising, err); + goto close; + } + + state = xenbus_read_integer(path); + while (err == NULL && + (state < XenbusStateInitWait || state >= XenbusStateClosed)) + err = xenbus_wait_for_state_change(path, &state); + +close: + free(err); + + snprintf(nodename, sizeof(nodename), "%s/ring-ref", dev->nodename); + err2 = xenbus_rm(XBT_NIL, nodename); + free(err2); + snprintf(nodename, sizeof(nodename), "%s/event-channel", dev->nodename); + err2 = xenbus_rm(XBT_NIL, nodename); + free(err2); + + if (!err) + free_blkfront(dev); } ulong pvblock_blk_read(struct udevice *udev, lbaint_t blknr, lbaint_t blkcnt, @@ -74,6 +338,7 @@ static int pvblock_blk_probe(struct udevice *udev) { struct blkfront_dev *blk_dev = dev_get_priv(udev); struct blkfront_platdata *platdata = dev_get_platdata(udev); + struct blk_desc *desc = dev_get_uclass_platdata(udev); int ret, devid; devid = platdata->devid; @@ -82,6 +347,11 @@ static int pvblock_blk_probe(struct udevice *udev) ret = init_blkfront(devid, blk_dev); if (ret < 0) return ret; + + desc->blksz = blk_dev->info.sector_size; + desc->lba = blk_dev->info.sectors; + desc->log2blksz = LOG2(blk_dev->info.sector_size); + return 0; }