diff options
| -rw-r--r-- | Documentation/lguest/lguest.c | 176 | ||||
| -rw-r--r-- | drivers/block/virtio_blk.c | 35 | ||||
| -rw-r--r-- | drivers/char/virtio_console.c | 4 | ||||
| -rw-r--r-- | drivers/lguest/lguest_device.c | 132 | ||||
| -rw-r--r-- | drivers/net/virtio_net.c | 25 | ||||
| -rw-r--r-- | drivers/virtio/virtio.c | 45 | ||||
| -rw-r--r-- | include/linux/lguest_launcher.h | 9 | ||||
| -rw-r--r-- | include/linux/virtio_blk.h | 22 | ||||
| -rw-r--r-- | include/linux/virtio_config.h | 98 | ||||
| -rw-r--r-- | include/linux/virtio_net.h | 11 | ||||
| -rw-r--r-- | net/9p/trans_virtio.c | 4 |
11 files changed, 280 insertions, 281 deletions
diff --git a/Documentation/lguest/lguest.c b/Documentation/lguest/lguest.c index 6c8a238..4df1804 100644 --- a/Documentation/lguest/lguest.c +++ b/Documentation/lguest/lguest.c @@ -34,6 +34,8 @@ #include <zlib.h> #include <assert.h> #include <sched.h> +#include <limits.h> +#include <stddef.h> #include "linux/lguest_launcher.h" #include "linux/virtio_config.h" #include "linux/virtio_net.h" @@ -99,13 +101,11 @@ struct device_list /* The descriptor page for the devices. */ u8 *descpage; - /* The tail of the last descriptor. */ - unsigned int desc_used; - /* A single linked list of devices. */ struct device *dev; - /* ... And an end pointer so we can easily append new devices */ - struct device **lastdev; + /* And a pointer to the last device for easy append and also for + * configuration appending. */ + struct device *lastdev; }; /* The list of Guest devices, based on command line arguments. */ @@ -191,7 +191,7 @@ static void *_convert(struct iovec *iov, size_t size, size_t align, #define cpu_to_le64(v64) (v64) #define le16_to_cpu(v16) (v16) #define le32_to_cpu(v32) (v32) -#define le64_to_cpu(v32) (v64) +#define le64_to_cpu(v64) (v64) /*L:100 The Launcher code itself takes us out into userspace, that scary place * where pointers run wild and free! Unfortunately, like most userspace @@ -986,54 +986,44 @@ static void handle_input(int fd) * * All devices need a descriptor so the Guest knows it exists, and a "struct * device" so the Launcher can keep track of it. We have common helper - * routines to allocate them. - * - * This routine allocates a new "struct lguest_device_desc" from descriptor - * table just above the Guest's normal memory. It returns a pointer to that - * descriptor. */ -static struct lguest_device_desc *new_dev_desc(u16 type) -{ - struct lguest_device_desc *d; + * routines to allocate and manage them. */ - /* We only have one page for all the descriptors. */ - if (devices.desc_used + sizeof(*d) > getpagesize()) - errx(1, "Too many devices"); - - /* We don't need to set config_len or status: page is 0 already. */ - d = (void *)devices.descpage + devices.desc_used; - d->type = type; - devices.desc_used += sizeof(*d); - - return d; +/* The layout of the device page is a "struct lguest_device_desc" followed by a + * number of virtqueue descriptors, then two sets of feature bits, then an + * array of configuration bytes. This routine returns the configuration + * pointer. */ +static u8 *device_config(const struct device *dev) +{ + return (void *)(dev->desc + 1) + + dev->desc->num_vq * sizeof(struct lguest_vqconfig) + + dev->desc->feature_len * 2; } -/* Each device descriptor is followed by some configuration information. - * Each configuration field looks like: u8 type, u8 len, [... len bytes...]. - * - * This routine adds a new field to an existing device's descriptor. It only - * works for the last device, but that's OK because that's how we use it. */ -static void add_desc_field(struct device *dev, u8 type, u8 len, const void *c) +/* This routine allocates a new "struct lguest_device_desc" from descriptor + * table page just above the Guest's normal memory. It returns a pointer to + * that descriptor. */ +static struct lguest_device_desc *new_dev_desc(u16 type) { - /* This is the last descriptor, right? */ - assert(devices.descpage + devices.desc_used - == (u8 *)(dev->desc + 1) + dev->desc->config_len); + struct lguest_device_desc d = { .type = type }; + void *p; - /* We only have one page of device descriptions. */ - if (devices.desc_used + 2 + len > getpagesize()) - errx(1, "Too many devices"); + /* Figure out where the next device config is, based on the last one. */ + if (devices.lastdev) + p = device_config(devices.lastdev) + + devices.lastdev->desc->config_len; + else + p = devices.descpage; - /* Copy in the new config header: type then length. */ - devices.descpage[devices.desc_used++] = type; - devices.descpage[devices.desc_used++] = len; - memcpy(devices.descpage + devices.desc_used, c, len); - devices.desc_used += len; + /* We only have one page for all the descriptors. */ + if (p + sizeof(d) > (void *)devices.descpage + getpagesize()) + errx(1, "Too many devices"); - /* Update the device descriptor length: two byte head then data. */ - dev->desc->config_len += 2 + len; + /* p might not be aligned, so we memcpy in. */ + return memcpy(p, &d, sizeof(d)); } -/* This routine adds a virtqueue to a device. We specify how many descriptors - * the virtqueue is to have. */ +/* Each device descriptor is followed by the description of its virtqueues. We + * specify how many descriptors the virtqueue is to have. */ static void add_virtqueue(struct device *dev, unsigned int num_descs, void (*handle_output)(int fd, struct virtqueue *me)) { @@ -1059,9 +1049,15 @@ static void add_virtqueue(struct device *dev, unsigned int num_descs, /* Initialize the vring. */ vring_init(&vq->vring, num_descs, p, getpagesize()); - /* Add the configuration information to this device's descriptor. */ - add_desc_field(dev, VIRTIO_CONFIG_F_VIRTQUEUE, - sizeof(vq->config), &vq->config); + /* Append virtqueue to this device's descriptor. We use + * device_config() to get the end of the device's current virtqueues; + * we check that we haven't added any config or feature information + * yet, otherwise we'd be overwriting them. */ + assert(dev->desc->config_len == 0 && dev->desc->feature_len == 0); + memcpy(device_config(dev), &vq->config, sizeof(vq->config)); + dev->desc->num_vq++; + + verbose("Virtqueue page %#lx\n", to_guest_phys(p)); /* Add to tail of list, so dev->vq is first vq, dev->vq->next is * second. */ @@ -1077,6 +1073,37 @@ static void add_virtqueue(struct device *dev, unsigned int num_descs, vq->vring.used->flags = VRING_USED_F_NO_NOTIFY; } +/* The virtqueue descriptors are followed by feature bytes. */ +static void add_feature(struct device *dev, unsigned bit) +{ + u8 *features; + + /* We can't extend the feature bits once we've added config bytes */ + if (dev->desc->feature_len <= bit / CHAR_BIT) { + assert(dev->desc->config_len == 0); + dev->desc->feature_len = (bit / CHAR_BIT) + 1; + } + + features = (u8 *)(dev->desc + 1) + + dev->desc->num_vq * sizeof(struct lguest_vqconfig); + + features[bit / CHAR_BIT] |= (1 << (bit % CHAR_BIT)); +} + +/* This routine sets the configuration fields for an existing device's + * descriptor. It only works for the last device, but that's OK because that's + * how we use it. */ +static void set_config(struct device *dev, unsigned len, const void *conf) +{ + /* Check we haven't overflowed our single page. */ + if (device_config(dev) + len > devices.descpage + getpagesize()) + errx(1, "Too many devices"); + + /* Copy in the config information, and store the length. */ + memcpy(device_config(dev), conf, len); + dev->desc->config_len = len; +} + /* This routine does all the creation and setup of a new device, including * calling new_dev_desc() to allocate the descriptor and device memory. */ static struct device *new_device(const char *name, u16 type, int fd, @@ -1084,14 +1111,6 @@ static struct device *new_device(const char *name, u16 type, int fd, { struct device *dev = malloc(sizeof(*dev)); - /* Append to device list. Prepending to a single-linked list is - * easier, but the user expects the devices to be arranged on the bus - * in command-line order. The first network device on the command line - * is eth0, the first block device /dev/vda, etc. */ - *devices.lastdev = dev; - dev->next = NULL; - devices.lastdev = &dev->next; - /* Now we populate the fields one at a time. */ dev->fd = fd; /* If we have an input handler for this file descriptor, then we add it @@ -1102,6 +1121,17 @@ static struct device *new_device(const char *name, u16 type, int fd, dev->handle_input = handle_input; dev->name = name; dev->vq = NULL; + + /* Append to device list. Prepending to a single-linked list is + * easier, but the user expects the devices to be arranged on the bus + * in command-line order. The first network device on the command line + * is eth0, the first block device /dev/vda, etc. */ + if (devices.lastdev) + devices.lastdev->next = dev; + else + devices.dev = dev; + devices.lastdev = dev; + return dev; } @@ -1226,7 +1256,7 @@ static void setup_tun_net(const char *arg) int netfd, ipfd; u32 ip; const char *br_name = NULL; - u8 hwaddr[6]; + struct virtio_net_config conf; /* We open the /dev/net/tun device and tell it we want a tap device. A * tap device is like a tun device, only somehow different. To tell @@ -1265,12 +1295,13 @@ static void setup_tun_net(const char *arg) ip = str2ip(arg); /* Set up the tun device, and get the mac address for the interface. */ - configure_device(ipfd, ifr.ifr_name, ip, hwaddr); + configure_device(ipfd, ifr.ifr_name, ip, conf.mac); /* Tell Guest what MAC address to use. */ - add_desc_field(dev, VIRTIO_CONFIG_NET_MAC_F, sizeof(hwaddr), hwaddr); + add_feature(dev, VIRTIO_NET_F_MAC); + set_config(dev, sizeof(conf), &conf); - /* We don't seed the socket any more; setup is done. */ + /* We don't need the socket any more; setup is done. */ close(ipfd); verbose("device %u: tun net %u.%u.%u.%u\n", @@ -1458,8 +1489,7 @@ static void setup_block_file(const char *filename) struct device *dev; struct vblk_info *vblk; void *stack; - u64 cap; - unsigned int val; + struct virtio_blk_config conf; /* This is the pipe the I/O thread will use to tell us I/O is done. */ pipe(p); @@ -1477,14 +1507,18 @@ static void setup_block_file(const char *filename) vblk->fd = open_or_die(filename, O_RDWR|O_LARGEFILE); vblk->len = lseek64(vblk->fd, 0, SEEK_END); + /* We support barriers. */ + add_feature(dev, VIRTIO_BLK_F_BARRIER); + /* Tell Guest how many sectors this device has. */ - cap = cpu_to_le64(vblk->len / 512); - add_desc_field(dev, VIRTIO_CONFIG_BLK_F_CAPACITY, sizeof(cap), &cap); + conf.capacity = cpu_to_le64(vblk->len / 512); /* Tell Guest not to put in too many descriptors at once: two are used * for the in and out elements. */ - val = cpu_to_le32(VIRTQUEUE_NUM - 2); - add_desc_field(dev, VIRTIO_CONFIG_BLK_F_SEG_MAX, sizeof(val), &val); + add_feature(dev, VIRTIO_BLK_F_SEG_MAX); + conf.seg_max = cpu_to_le32(VIRTQUEUE_NUM - 2); + + set_config(dev, sizeof(conf), &conf); /* The I/O thread writes to this end of the pipe when done. */ vblk->done_fd = p[1]; @@ -1505,7 +1539,7 @@ static void setup_block_file(const char *filename) close(vblk->workpipe[0]); verbose("device %u: virtblock %llu sectors\n", - devices.device_num, cap); + devices.device_num, le64_to_cpu(conf.capacity)); } /* That's the end of device setup. :*/ @@ -1610,12 +1644,12 @@ int main(int argc, char *argv[]) /* First we initialize the device list. Since console and network * device receive input from a file descriptor, we keep an fdset * (infds) and the maximum fd number (max_infd) with the head of the - * list. We also keep a pointer to the last device, for easy appending - * to the list. Finally, we keep the next interrupt number to hand out - * (1: remember that 0 is used by the timer). */ + * list. We also keep a pointer to the last device. Finally, we keep + * the next interrupt number to hand out (1: remember that 0 is used by + * the timer). */ FD_ZERO(&devices.infds); devices.max_infd = -1; - devices.lastdev = &devices.dev; + devices.lastdev = NULL; devices.next_irq = 1; cpu_id = 0; diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 924ddd8..1c63d5b 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -162,8 +162,6 @@ static int virtblk_probe(struct virtio_device *vdev) { struct virtio_blk *vblk; int err, major; - void *token; - unsigned int len; u64 cap; u32 v; @@ -178,7 +176,7 @@ static int virtblk_probe(struct virtio_device *vdev) vblk->vdev = vdev; /* We expect one virtqueue, for output. */ - vblk->vq = vdev->config->find_vq(vdev, blk_done); + vblk->vq = vdev->config->find_vq(vdev, 0, blk_done); if (IS_ERR(vblk->vq)) { err = PTR_ERR(vblk->vq); goto out_free_vblk; @@ -216,15 +214,12 @@ static int virtblk_probe(struct virtio_device *vdev) vblk->disk->fops = &virtblk_fops; /* If barriers are supported, tell block layer that queue is ordered */ - token = vdev->config->find(vdev, VIRTIO_CONFIG_BLK_F, &len); - if (virtio_use_bit(vdev, token, len, VIRTIO_BLK_F_BARRIER)) + if (vdev->config->feature(vdev, VIRTIO_BLK_F_BARRIER)) blk_queue_ordered(vblk->disk->queue, QUEUE_ORDERED_TAG, NULL); - err = virtio_config_val(vdev, VIRTIO_CONFIG_BLK_F_CAPACITY, &cap); - if (err) { - dev_err(&vdev->dev, "Bad/missing capacity in config\n"); - goto out_cleanup_queue; - } + /* Host must always specify the capacity. */ + __virtio_config_val(vdev, offsetof(struct virtio_blk_config, capacity), + &cap); /* If capacity is too big, truncate with warning. */ if ((sector_t)cap != cap) { @@ -234,27 +229,23 @@ static int virtblk_probe(struct virtio_device *vdev) } set_capacity(vblk->disk, cap); - err = virtio_config_val(vdev, VIRTIO_CONFIG_BLK_F_SIZE_MAX, &v); + /* Host can optionally specify maximum segment size and number of + * segments. */ + err = virtio_config_val(vdev, VIRTIO_BLK_F_SIZE_MAX, + offsetof(struct virtio_blk_config, size_max), + &v); if (!err) blk_queue_max_segment_size(vblk->disk->queue, v); - else if (err != -ENOENT) { - dev_err(&vdev->dev, "Bad SIZE_MAX in config\n"); - goto out_cleanup_queue; - } - err = virtio_config_val(vdev, VIRTIO_CONFIG_BLK_F_SEG_MAX, &v); + err = virtio_config_val(vdev, VIRTIO_BLK_F_SEG_MAX, + offsetof(struct virtio_blk_config, seg_max), + &v); if (!err) blk_queue_max_hw_segments(vblk->disk->queue, v); - else if (err != -ENOENT) { - dev_err(&vdev->dev, "Bad SEG_MAX in config\n"); - goto out_cleanup_queue; - } add_disk(vblk->disk); return 0; -out_cleanup_queue: - blk_cleanup_queue(vblk->disk->queue); out_put_disk: put_disk(vblk->disk); out_unregister_blkdev: diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c index e34da5c..dc17fe3 100644 --- a/drivers/char/virtio_console.c +++ b/drivers/char/virtio_console.c @@ -158,13 +158,13 @@ static int __devinit virtcons_probe(struct virtio_device *dev) /* Find the input queue. */ /* FIXME: This is why we want to wean off hvc: we do nothing * when input comes in. */ - in_vq = vdev->config->find_vq(vdev, NULL); + in_vq = vdev->config->find_vq(vdev, 0, NULL); if (IS_ERR(in_vq)) { err = PTR_ERR(in_vq); goto free; } - out_vq = vdev->config->find_vq(vdev, NULL); + out_vq = vdev->config->find_vq(vdev, 1, NULL); if (IS_ERR(out_vq)) { err = PTR_ERR(out_vq); goto free_in_vq; diff --git a/drivers/lguest/lguest_device.c b/drivers/lguest/lguest_device.c index e2eec38..07f57a5 100644 --- a/drivers/lguest/lguest_device.c +++ b/drivers/lguest/lguest_device.c @@ -52,57 +52,82 @@ struct lguest_device { /*D:130 * Device configurations * - * The configuration information for a device consists of a series of fields. - * We don't really care what they are: the Launcher set them up, and the driver - * will look at them during setup. + * The configuration information for a device consists of one or more + * virtqueues, a feature bitmaks, and some configuration bytes. The + * configuration bytes don't really matter to us: the Launcher set them up, and + * the driver will look at them during setup. * - * For us these fields come immediately after that device's descriptor in the - * lguest_devices page. - * - * Each field starts with a "type" byte, a "length" byte, then that number of - * bytes of configuration information. The device descriptor tells us the - * total configuration length so we know when we've reached the last field. */ + * A convenient routine to return the device's virtqueue config array: + * immediately after the descriptor. */ +static struct lguest_vqconfig *lg_vq(const struct lguest_device_desc *desc) +{ + return (void *)(desc + 1); +} -/* type + length bytes */ -#define FHDR_LEN 2 +/* The features come immediately after the virtqueues. */ +static u8 *lg_features(const struct lguest_device_desc *desc) +{ + return (void *)(lg_vq(desc) + desc->num_vq); +} -/* This finds the first field of a given type for a device's configuration. */ -static void *lg_find(struct virtio_device *vdev, u8 type, unsigned int *len) +/* The config space comes after the two feature bitmasks. */ +static u8 *lg_config(const struct lguest_device_desc *desc) { - struct lguest_device_desc *desc = to_lgdev(vdev)->desc; - int i; - - for (i = 0; i < desc->config_len; i += FHDR_LEN + desc->config[i+1]) { - if (desc->config[i] == type) { - /* Mark it used, so Host can know we looked at it, and - * also so we won't find the same one twice. */ - desc->config[i] |= 0x80; - /* Remember, the second byte is the length. */ - *len = desc->config[i+1]; - /* We return a pointer to the field header. */ - return desc->config + i; - } - } + return lg_features(desc) + desc->feature_len * 2; +} - /* Not found: return NULL for failure. */ - return NULL; +/* The total size of the config page used by this device (incl. desc) */ +static unsigned desc_size(const struct lguest_device_desc *desc) +{ + return sizeof(*desc) + + desc->num_vq * sizeof(struct lguest_vqconfig) + + desc->feature_len * 2 + + desc->config_len; +} + +/* This tests (and acknowleges) a feature bit. */ +static bool lg_feature(struct virtio_device *vdev, unsigned fbit) +{ + struct lguest_device_desc *desc = to_lgdev(vdev)->desc; + u8 *features; + + /* Obviously if they ask for a feature off the end of our feature + * bitmap, it's not set. */ + if (fbit / 8 > desc->feature_len) + return false; + + /* The feature bitmap comes after the virtqueues. */ + features = lg_features(desc); + if (!(features[fbit / 8] & (1 << (fbit % 8)))) + return false; + + /* We set the matching bit in the other half of the bitmap to tell the + * Host we want to use this feature. We don't use this yet, but we + * could in future. */ + features[desc->feature_len + fbit / 8] |= (1 << (fbit % 8)); + return true; } /* Once they've found a field, getting a copy of it is easy. */ -static void lg_get(struct virtio_device *vdev, void *token, +static void lg_get(struct virtio_device *vdev, unsigned int offset, void *buf, unsigned len) { - /* Check they didn't ask for more than the length of the field! */ - BUG_ON(len > ((u8 *)token)[1]); - memcpy(buf, token + FHDR_LEN, len); + struct lguest_device_desc *desc = to_lgdev(vdev)->desc; + + /* Check they didn't ask for more than the length of the config! */ + BUG_ON(offset + len > desc->config_len); + memcpy(buf, lg_config(desc) + offset, len); } /* Setting the contents is also trivial. */ -static void lg_set(struct virtio_device *vdev, void *token, +static void lg_set(struct virtio_device *vdev, unsigned int offset, const void *buf, unsigned len) { - BUG_ON(len > ((u8 *)token)[1]); - memcpy(token + FHDR_LEN, buf, len); + struct lguest_device_desc *desc = to_lgdev(vdev)->desc; + + /* Check they didn't ask for more than the length of the config! */ + BUG_ON(offset + len > desc->config_len); + memcpy(lg_config(desc) + offset, buf, len); } /* The operations to get and set the status word just access the status field @@ -165,39 +190,29 @@ static void lg_notify(struct virtqueue *vq) * * So we provide devices with a "find virtqueue and set it up" function. */ static struct virtqueue *lg_find_vq(struct virtio_device *vdev, + unsigned index, bool (*callback)(struct virtqueue *vq)) { + struct lguest_device *ldev = to_lgdev(vdev); struct lguest_vq_info *lvq; struct virtqueue *vq; - unsigned int len; - void *token; int err; - /* Look for a field of the correct type to mark a virtqueue. Note that - * if this succeeds, then the type will be changed so it won't be found - * again, and future lg_find_vq() calls will find the next - * virtqueue (if any). */ - token = vdev->config->find(vdev, VIRTIO_CONFIG_F_VIRTQUEUE, &len); - if (!token) + /* We must have this many virtqueues. */ + if (index >= ldev->desc->num_vq) return ERR_PTR(-ENOENT); lvq = kmalloc(sizeof(*lvq), GFP_KERNEL); if (!lvq) return ERR_PTR(-ENOMEM); - /* Note: we could use a configuration space inside here, just like we - * do for the device. This would allow expansion in future, because - * our configuration system is designed to be expansible. But this is - * way easier. */ - if (len != sizeof(lvq->config)) { - dev_err(&vdev->dev, "Unexpected virtio config len %u\n", len); - err = -EIO; - goto free_lvq; - } - /* Make a copy of the "struct lguest_vqconfig" field. We need a copy - * because the config space might not be aligned correctly. */ - vdev->config->get(vdev, token, &lvq->config, sizeof(lvq->config)); + /* Make a copy of the "struct lguest_vqconfig" entry, which sits after + * the descriptor. We need a copy because the config space might not + * be aligned correctly. */ + memcpy(&lvq->config, lg_vq(ldev->desc)+index, sizeof(lvq->config)); + printk("Mapping virtqueue %i addr %lx\n", index, + (unsigned long)lvq->config.pfn << PAGE_SHIFT); /* Figure out how many pages the ring will take, and map that memory */ lvq->pages = lguest_map((unsigned long)lvq->config.pfn << PAGE_SHIFT, DIV_ROUND_UP(vring_size(lvq->config.num, @@ -259,7 +274,7 @@ static void lg_del_vq(struct virtqueue *vq) /* The ops structure which hooks everything together. */ static struct virtio_config_ops lguest_config_ops = { - .find = lg_find, + .feature = lg_feature, .get = lg_get, .set = lg_set, .get_status = lg_get_status, @@ -329,13 +344,14 @@ static void scan_devices(void) struct lguest_device_desc *d; /* We start at the page beginning, and skip over each entry. */ - for (i = 0; i < PAGE_SIZE; i += sizeof(*d) + d->config_len) { + for (i = 0; i < PAGE_SIZE; i += desc_size(d)) { d = lguest_devices + i; /* Once we hit a zero, stop. */ if (d->type == 0) break; + printk("Device at %i has size %u\n", i, desc_size(d)); add_lguest_device(d); } } diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index a60505c..4b81383 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -311,10 +311,8 @@ static int virtnet_close(struct net_device *dev) static int virtnet_probe(struct virtio_device *vdev) { int err; - unsigned int len; struct net_device *dev; struct virtnet_info *vi; - void *token; /* Allocate ourselves a network device with room for our info */ dev = alloc_etherdev(sizeof(struct virtnet_info)); @@ -330,25 +328,24 @@ static int virtnet_probe(struct virtio_device *vdev) SET_NETDEV_DEV(dev, &vdev->dev); /* Do we support "hardware" checksums? */ - token = vdev->config->find(vdev, VIRTIO_CONFIG_NET_F, &len); - if (virtio_use_bit(vdev, token, len, VIRTIO_NET_F_NO_CSUM)) { + if (vdev->config->feature(vdev, VIRTIO_NET_F_NO_CSUM)) { /* This opens up the world of extra features. */ dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST; - if (virtio_use_bit(vdev, token, len, VIRTIO_NET_F_TSO4)) + if (vdev->config->feature(vdev, VIRTIO_NET_F_TSO4)) dev->features |= NETIF_F_TSO; - if (virtio_use_bit(vdev, token, len, VIRTIO_NET_F_UFO)) + if (vdev->config->feature(vdev, VIRTIO_NET_F_UFO)) dev->features |= NETIF_F_UFO; - if (virtio_use_bit(vdev, token, len, VIRTIO_NET_F_TSO4_ECN)) + if (vdev->config->feature(vdev, VIRTIO_NET_F_TSO4_ECN)) dev->features |= NETIF_F_TSO_ECN; - if (virtio_use_bit(vdev, token, len, VIRTIO_NET_F_TSO6)) + if (vdev->config->feature(vdev, VIRTIO_NET_F_TSO6)) dev->features |= NETIF_F_TSO6; } /* Configuration may specify what MAC to use. Otherwise random. */ - token = vdev->config->find(vdev, VIRTIO_CONFIG_NET_MAC_F, &len); - if (token) { - dev->addr_len = len; - vdev->config->get(vdev, token, dev->dev_addr, len); + if (vdev->config->feature(vdev, VIRTIO_NET_F_MAC)) { + vdev->config->get(vdev, + offsetof(struct virtio_net_config, mac), + dev->dev_addr, dev->addr_len); } else random_ether_addr(dev->dev_addr); @@ -359,13 +356,13 @@ static int virtnet_probe(struct virtio_device *vdev) vi->vdev = vdev; /* We expect two virtqueues, receive then send. */ - vi->rvq = vdev->config->find_vq(vdev, skb_recv_done); + vi->rvq = vdev->config->find_vq(vdev, 0, skb_recv_done); if (IS_ERR(vi->rvq)) { err = PTR_ERR(vi->rvq); goto free; } - vi->svq = vdev->config->find_vq(vdev, skb_xmit_done); + vi->svq = vdev->config->find_vq(vdev, 1, skb_xmit_done); if (IS_ERR(vi->svq)) { err = PTR_ERR(vi->svq); goto free_recv; diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c index 69d7ea0..303cb6f 100644 --- a/drivers/virtio/virtio.c +++ b/drivers/virtio/virtio.c @@ -148,51 +148,6 @@ void unregister_virtio_device(struct virtio_device *dev) } EXPORT_SYMBOL_GPL(unregister_virtio_device); -int __virtio_config_val(struct virtio_device *vdev, - u8 type, void *val, size_t size) -{ - void *token; - unsigned int len; - - token = vdev->config->find(vdev, type, &len); - if (!token) - return -ENOENT; - - if (len != size) - return -EIO; - - vdev->config->get(vdev, token, val, size); - return 0; -} -EXPORT_SYMBOL_GPL(__virtio_config_val); - -int virtio_use_bit(struct virtio_device *vdev, - void *token, unsigned int len, unsigned int bitnum) -{ - unsigned long bits[16]; - - /* This makes it convenient to pass-through find() results. */ - if (!token) - return 0; - - /* bit not in range of this bitfield? */ - if (bitnum * 8 >= len / 2) - return 0; - - /* Giant feature bitfields are silly. */ - BUG_ON(len > sizeof(bits)); - vdev->config->get(vdev, token, bits, len); - - if (!test_bit(bitnum, bits)) - return 0; - - /* Set acknowledge bit, and write it back. */ - set_bit(bitnum + len * 8 / 2, bits); - vdev->config->set(vdev, token, bits, len); - return 1; -} -EXPORT_SYMBOL_GPL(virtio_use_bit); - static int virtio_init(void) { if (bus_register(&virtio_bus) != 0) diff --git a/include/linux/lguest_launcher.h b/include/linux/lguest_launcher.h index 697104d..589be3e 100644 --- a/include/linux/lguest_launcher.h +++ b/include/linux/lguest_launcher.h @@ -23,7 +23,12 @@ struct lguest_device_desc { /* The device type: console, network, disk etc. Type 0 terminates. */ __u8 type; - /* The number of bytes of the config array. */ + /* The number of virtqueues (first in config array) */ + __u8 num_vq; + /* The number of bytes of feature bits. Multiply by 2: one for host + * features and one for guest acknowledgements. */ + __u8 feature_len; + /* The number of bytes of the config array after virtqueues. */ __u8 config_len; /* A status byte, written by the Guest. */ __u8 status; @@ -31,7 +36,7 @@ struct lguest_device_desc { }; /*D:135 This is how we expect the device configuration field for a virtqueue - * (type VIRTIO_CONFIG_F_VIRTQUEUE) to be laid out: */ + * to be laid out in config space. */ struct lguest_vqconfig { /* The number of entries in the virtio_ring */ __u16 num; diff --git a/include/linux/virtio_blk.h b/include/linux/virtio_blk.h index 7bd2bce..e546356 100644 --- a/include/linux/virtio_blk.h +++ b/include/linux/virtio_blk.h @@ -6,15 +6,19 @@ #define VIRTIO_ID_BLOCK 2 /* Feature bits */ -#define VIRTIO_CONFIG_BLK_F 0x40 -#define VIRTIO_BLK_F_BARRIER 1 /* Does host support barriers? */ - -/* The capacity (in 512-byte sectors). */ -#define VIRTIO_CONFIG_BLK_F_CAPACITY 0x41 -/* The maximum segment size. */ -#define VIRTIO_CONFIG_BLK_F_SIZE_MAX 0x42 -/* The maximum number of segments. */ -#define VIRTIO_CONFIG_BLK_F_SEG_MAX 0x43 +#define VIRTIO_BLK_F_BARRIER 0 /* Does host support barriers? */ +#define VIRTIO_BLK_F_SIZE_MAX 1 /* Indicates maximum segment size */ +#define VIRTIO_BLK_F_SEG_MAX 2 /* Indicates maximum # of segments */ + +struct virtio_blk_config +{ + /* The capacity (in 512-byte sectors). */ + __le64 capacity; + /* The maximum segment size (if VIRTIO_BLK_F_SIZE_MAX) */ + __le32 size_max; + /* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */ + __le32 seg_max; +} __attribute__((packed)); /* These two define direction. */ #define VIRTIO_BLK_T_IN 0 diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index bcc0188..70bb260 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -5,7 +5,7 @@ * store and access that space differently. */ #include <linux/types.h> -/* Status byte for guest to report progress, and synchronize config. */ +/* Status byte for guest to report progress, and synchronize features. */ /* We have seen device and processed generic fields (VIRTIO_CONFIG_F_VIRTIO) */ #define VIRTIO_CONFIG_S_ACKNOWLEDGE 1 /* We have found a driver for the device. */ @@ -15,34 +15,27 @@ /* We've given up on this device. */ #define VIRTIO_CONFIG_S_FAILED 0x80 -/* Feature byte (actually 7 bits availabe): */ -/* Requirements/features of the virtio implementation. */ -#define VIRTIO_CONFIG_F_VIRTIO 1 -/* Requirements/features of the virtqueue (may have more than one). */ -#define VIRTIO_CONFIG_F_VIRTQUEUE 2 - #ifdef __KERNEL__ struct virtio_device; /** * virtio_config_ops - operations for configuring a virtio device - * @find: search for the next configuration field of the given type. + * @feature: search for a feature in this config * vdev: the virtio_device - * type: the feature type - * len: the (returned) length of the field if found. - * Returns a token if found, or NULL. Never returnes the same field twice - * (ie. it's used up). - * @get: read the value of a configuration field after find(). + * bit: the feature bit + * Returns true if the feature is supported. Acknowledges the feature + * so the host can see it. + * @get: read the value of a configuration field * vdev: the virtio_device - * token: the token returned from find(). + * offset: the offset of the configuration field * buf: the buffer to write the field value into. - * len: the length of the buffer (given by find()). + * len: the length of the buffer * Note that contents are conventionally little-endian. - * @set: write the value of a configuration field after find(). + * @set: write the value of a configuration field * vdev: the virtio_device - * token: the token returned from find(). + * offset: the offset of the configuration field * buf: the buffer to read the field value from. - * len: the length of the buffer (given by find()). + * len: the length of the buffer * Note that contents are conventionally little-endian. * @get_status: read the status byte * vdev: the virtio_device @@ -50,62 +43,63 @@ struct virtio_device; * @set_status: write the status byte * vdev: the virtio_device * status: the new status byte - * @find_vq: find the first VIRTIO_CONFIG_F_VIRTQUEUE and create a virtqueue. + * @find_vq: find a virtqueue and instantiate it. * vdev: the virtio_device + * index: the 0-based virtqueue number in case there's more than one. * callback: the virqtueue callback - * Returns the new virtqueue or ERR_PTR(). + * Returns the new virtqueue or ERR_PTR() (eg. -ENOENT). * @del_vq: free a virtqueue found by find_vq(). */ struct virtio_config_ops { - void *(*find)(struct virtio_device *vdev, u8 type, unsigned *len); - void (*get)(struct virtio_device *vdev, void *token, + bool (*feature)(struct virtio_device *vdev, unsigned bit); + void (*get)(struct virtio_device *vdev, unsigned offset, void *buf, unsigned len); - void (*set)(struct virtio_device *vdev, void *token, + void (*set)(struct virtio_device *vdev, unsigned offset, const void *buf, unsigned len); u8 (*get_status)(struct virtio_device *vdev); void (*set_status)(struct virtio_device *vdev, u8 status); struct virtqueue *(*find_vq)(struct virtio_device *vdev, + unsigned index, bool (*callback)(struct virtqueue *)); void (*del_vq)(struct virtqueue *vq); }; /** - * virtio_config_val - get a single virtio config and mark it used. - * @config: the virtio config space - * @type: the type to search for. + * virtio_config_val - look for a feature and get a single virtio config. + * @vdev: the virtio device + * @fbit: the feature bit + * @offset: the type to search for. * @val: a pointer to the value to fill in. * - * Once used, the config type is marked with VIRTIO_CONFIG_F_USED so it can't - * be found again. This version does endian conversion. */ -#define virtio_config_val(vdev, type, v) ({ \ - int _err = __virtio_config_val((vdev),(type),(v),sizeof(*(v))); \ - \ - BUILD_BUG_ON(sizeof(*(v)) != 1 && sizeof(*(v)) != 2 \ - && sizeof(*(v)) != 4 && sizeof(*(v)) != 8); \ - if (!_err) { \ - switch (sizeof(*(v))) { \ - case 2: le16_to_cpus((__u16 *) v); break; \ - case 4: le32_to_cpus((__u32 *) v); break; \ - case 8: le64_to_cpus((__u64 *) v); break; \ - } \ - } \ + * The return value is -ENOENT if the feature doesn't exist. Otherwise + * the value is endian-corrected and returned in v. */ +#define virtio_config_val(vdev, fbit, offset, v) ({ \ + int _err; \ + if ((vdev)->config->feature((vdev), (fbit))) { \ + __virtio_config_val((vdev), (offset), (v)); \ + _err = 0; \ + } else \ + _err = -ENOENT; \ _err; \ }) -int __virtio_config_val(struct virtio_device *dev, - u8 type, void *val, size_t size); - /** - * virtio_use_bit - helper to use a feature bit in a bitfield value. - * @dev: the virtio device - * @token: the token as returned from vdev->config->find(). - * @len: the length of the field. - * @bitnum: the bit to test. + * __virtio_config_val - get a single virtio config without feature check. + * @vdev: the virtio device + * @offset: the type to search for. + * @val: a pointer to the value to fill in. * - * If handed a NULL token, it returns false, otherwise returns bit status. - * If it's one, it sets the mirroring acknowledgement bit. */ -int virtio_use_bit(struct virtio_device *vdev, - void *token, unsigned int len, unsigned int bitnum); + * The value is endian-corrected and returned in v. */ +#define __virtio_config_val(vdev, offset, v) do { \ + BUILD_BUG_ON(sizeof(*(v)) != 1 && sizeof(*(v)) != 2 \ + && sizeof(*(v)) != 4 && sizeof(*(v)) != 8); \ + (vdev)->config->get((vdev), (offset), (v), sizeof(*(v))); \ + switch (sizeof(*(v))) { \ + case 2: le16_to_cpus((__u16 *) v); break; \ + case 4: le32_to_cpus((__u32 *) v); break; \ + case 8: le64_to_cpus((__u64 *) v); break; \ + } \ +} while(0) #endif /* __KERNEL__ */ #endif /* _LINUX_VIRTIO_CONFIG_H */ diff --git a/include/linux/virtio_net.h b/include/linux/virtio_net.h index ae469ae..6e8fdfe 100644 --- a/include/linux/virtio_net.h +++ b/include/linux/virtio_net.h @@ -5,16 +5,19 @@ /* The ID for virtio_net */ #define VIRTIO_ID_NET 1 -/* The bitmap of config for virtio net */ -#define VIRTIO_CONFIG_NET_F 0x40 +/* The feature bitmap for virtio net */ #define VIRTIO_NET_F_NO_CSUM 0 #define VIRTIO_NET_F_TSO4 1 #define VIRTIO_NET_F_UFO 2 #define VIRTIO_NET_F_TSO4_ECN 3 #define VIRTIO_NET_F_TSO6 4 +#define VIRTIO_NET_F_MAC 5 -/* The config defining mac address. */ -#define VIRTIO_CONFIG_NET_MAC_F 0x41 +struct virtio_net_config +{ + /* The config defining mac address (if VIRTIO_NET_F_MAC) */ + __u8 mac[6]; +} __attribute__((packed)); /* This is the first element of the scatter-gather list. If you don't * specify GSO or CSUM features, you can simply ignore the header. */ diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c index 40b71a2..78d7946 100644 --- a/net/9p/trans_virtio.c +++ b/net/9p/trans_virtio.c @@ -236,13 +236,13 @@ static int p9_virtio_probe(struct virtio_device *dev) /* Find the input queue. */ dev->priv = chan; - chan->in_vq = dev->config->find_vq(dev, p9_virtio_intr); + chan->in_vq = dev->config->find_vq(dev, 0, p9_virtio_intr); if (IS_ERR(chan->in_vq)) { err = PTR_ERR(chan->in_vq); goto free; } - chan->out_vq = dev->config->find_vq(dev, NULL); + chan->out_vq = dev->config->find_vq(dev, 1, NULL); if (IS_ERR(chan->out_vq)) { err = PTR_ERR(chan->out_vq); goto free_in_vq; |
