From 3ef536095446552823fc488fec1c5451aab1260d Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Fri, 16 May 2008 11:17:03 +0200 Subject: virtio_blk: allow read-only disks Hello Rusty, sometimes it is useful to share a disk (e.g. usr). To avoid file system corruption, the disk should be mounted read-only in that case. This patch adds a new feature flag, that allows the host to specify, if the disk should be considered read-only. Signed-off-by: Christian Borntraeger Signed-off-by: Rusty Russell --- include/linux/virtio_blk.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/linux/virtio_blk.h b/include/linux/virtio_blk.h index d4695a3356d..b80919fad0e 100644 --- a/include/linux/virtio_blk.h +++ b/include/linux/virtio_blk.h @@ -10,6 +10,7 @@ #define VIRTIO_BLK_F_SIZE_MAX 1 /* Indicates maximum segment size */ #define VIRTIO_BLK_F_SEG_MAX 2 /* Indicates maximum # of segments */ #define VIRTIO_BLK_F_GEOMETRY 4 /* Legacy geometry available */ +#define VIRTIO_BLK_F_RO 5 /* Disk is read-only */ struct virtio_blk_config { -- cgit v1.2.3 From f7f510ec195781c857ab76366a3e1c59e1caae42 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Fri, 30 May 2008 15:09:44 -0500 Subject: virtio: An entropy device, as suggested by hpa. Note that by itself, having a "hardware" random generator does very little: you should probably run "rngd" in your guest to feed this into the kernel entropy pool. Included: virtio_rng: dont use vmalloced addresses for virtio If virtio_rng is build as a module, random_data is an address in vmalloc space. As virtio expects guest real addresses, this can cause any kind of funny behaviour, so lets allocate random_data dynamically with kmalloc. Signed-off-by: Christian Borntraeger Signed-off-by: Rusty Russell --- include/linux/virtio_rng.h | 8 ++++++++ 1 file changed, 8 insertions(+) create mode 100644 include/linux/virtio_rng.h (limited to 'include') diff --git a/include/linux/virtio_rng.h b/include/linux/virtio_rng.h new file mode 100644 index 00000000000..331afb6c9f6 --- /dev/null +++ b/include/linux/virtio_rng.h @@ -0,0 +1,8 @@ +#ifndef _LINUX_VIRTIO_RNG_H +#define _LINUX_VIRTIO_RNG_H +#include + +/* The ID for virtio_rng */ +#define VIRTIO_ID_RNG 4 + +#endif /* _LINUX_VIRTIO_RNG_H */ -- cgit v1.2.3 From 7f31fe05000af54e1af81f65a96cab90db8d7ed8 Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Thu, 29 May 2008 11:08:01 +0200 Subject: virtio_config: fix len calculation of config elements Rusty, This patch is a prereq for the virtio_blk blocksize patch, please apply it first. Adding an u32 value to the virtio_blk_config unconvered a small bug the config space defintions: v is a pointer, to we have to use sizeof(*v) instead of sizeof(v). Signed-off-by: Christian Borntraeger Signed-off-by: Rusty Russell --- include/linux/virtio_config.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index 50db245c81a..71d6c102497 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -99,7 +99,7 @@ static inline bool virtio_has_feature(const struct virtio_device *vdev, * The return value is -ENOENT if the feature doesn't exist. Otherwise * the config value is copied into whatever is pointed to by v. */ #define virtio_config_val(vdev, fbit, offset, v) \ - virtio_config_buf((vdev), (fbit), (offset), (v), sizeof(v)) + virtio_config_buf((vdev), (fbit), (offset), (v), sizeof(*v)) static inline int virtio_config_buf(struct virtio_device *vdev, unsigned int fbit, -- cgit v1.2.3 From 7757f09c70af87887dfc195e6d6ddd54f5cc7c39 Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Thu, 29 May 2008 11:10:01 +0200 Subject: virtio_blk: fix endianess annotations Since commit 72e61eb40b55dd57031ec5971e810649f82b0259 (virtio: change config to guest endian) config space is no longer fixed endian. Lets change the virtio_blk_config variables. Signed-off-by: Christian Borntraeger Signed-off-by: Rusty Russell --- include/linux/virtio_blk.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/include/linux/virtio_blk.h b/include/linux/virtio_blk.h index b80919fad0e..5f79a5f9de7 100644 --- a/include/linux/virtio_blk.h +++ b/include/linux/virtio_blk.h @@ -15,14 +15,14 @@ struct virtio_blk_config { /* The capacity (in 512-byte sectors). */ - __le64 capacity; + __u64 capacity; /* The maximum segment size (if VIRTIO_BLK_F_SIZE_MAX) */ - __le32 size_max; + __u32 size_max; /* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */ - __le32 seg_max; + __u32 seg_max; /* geometry the device (if VIRTIO_BLK_F_GEOMETRY) */ struct virtio_blk_geometry { - __le16 cylinders; + __u16 cylinders; __u8 heads; __u8 sectors; } geometry; -- cgit v1.2.3 From b4f68be6c5d507afdcd74f5be3df0b1209cda503 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Fri, 30 May 2008 15:09:45 -0500 Subject: virtio: force callback on empty. virtio allows drivers to suppress callbacks (ie. interrupts) for efficiency (no locking, it's just an optimization). There's a similar mechanism for the host to suppress notifications coming from the guest: in that case, we ignore the suppression if the ring is completely full. It turns out that life is simpler if the host similarly ignores callback suppression when the ring is completely empty: the network driver wants to free up old packets in a timely manner, and otherwise has to use a timer to poll. We have to remove the code which ignores interrupts when the driver has disabled them (again, it had no locking and hence was unreliable anyway). Signed-off-by: Rusty Russell --- include/linux/virtio_config.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include') diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index 71d6c102497..f364bbf63c3 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -15,6 +15,10 @@ /* We've given up on this device. */ #define VIRTIO_CONFIG_S_FAILED 0x80 +/* Do we get callbacks when the ring is completely used, even if we've + * suppressed them? */ +#define VIRTIO_F_NOTIFY_ON_EMPTY 24 + #ifdef __KERNEL__ #include -- cgit v1.2.3