From 3c1b27d5043086a485f8526353ae9fe37bfa1065 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Wed, 23 Sep 2009 22:26:31 -0600 Subject: virtio: make add_buf return capacity remaining This API change means that virtio_net can tell how much capacity remains for buffers. It's necessarily fuzzy, since VIRTIO_RING_F_INDIRECT_DESC means we can fit any number of descriptors in one, *if* we can kmalloc. Signed-off-by: Rusty Russell Cc: Dinesh Subhraveti --- include/linux/virtio.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/virtio.h b/include/linux/virtio.h index 4fca4f5440ba..057a2e010758 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -34,7 +34,7 @@ struct virtqueue { * out_num: the number of sg readable by other side * in_num: the number of sg which are writable (after readable ones) * data: the token identifying the buffer. - * Returns 0 or an error. + * Returns remaining capacity of queue (sg segments) or a negative error. * @kick: update after add_buf * vq: the struct virtqueue * After one or more add_buf calls, invoke this to kick the other side. -- cgit v1.2.3 From 3ca4f5ca73057a617f9444a91022d7127041970a Mon Sep 17 00:00:00 2001 From: Fernando Luis Vazquez Cao Date: Fri, 31 Jul 2009 15:25:56 +0900 Subject: virtio: add virtio IDs file Virtio IDs are spread all over the tree which makes assigning new IDs bothersome. Putting them together should make the process less error-prone. Signed-off-by: Fernando Luis Vazquez Cao Signed-off-by: Rusty Russell --- Documentation/lguest/lguest.c | 1 + drivers/block/virtio_blk.c | 1 + drivers/char/hw_random/virtio-rng.c | 1 + drivers/char/virtio_console.c | 1 + drivers/net/virtio_net.c | 1 + drivers/virtio/virtio_balloon.c | 1 + include/linux/virtio_9p.h | 2 -- include/linux/virtio_balloon.h | 3 --- include/linux/virtio_blk.h | 3 --- include/linux/virtio_console.h | 3 --- include/linux/virtio_ids.h | 17 +++++++++++++++++ include/linux/virtio_net.h | 3 --- include/linux/virtio_rng.h | 3 --- net/9p/trans_virtio.c | 1 + 14 files changed, 24 insertions(+), 17 deletions(-) create mode 100644 include/linux/virtio_ids.h (limited to 'include') diff --git a/Documentation/lguest/lguest.c b/Documentation/lguest/lguest.c index 950cde6d6e58..84bbb190bf7b 100644 --- a/Documentation/lguest/lguest.c +++ b/Documentation/lguest/lguest.c @@ -42,6 +42,7 @@ #include #include "linux/lguest_launcher.h" #include "linux/virtio_config.h" +#include #include "linux/virtio_net.h" #include "linux/virtio_blk.h" #include "linux/virtio_console.h" diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index d739ee4201f9..73de7532fcf5 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -3,6 +3,7 @@ #include #include #include +#include #include #include diff --git a/drivers/char/hw_random/virtio-rng.c b/drivers/char/hw_random/virtio-rng.c index b6c24dcc987d..962968f05b94 100644 --- a/drivers/char/hw_random/virtio-rng.c +++ b/drivers/char/hw_random/virtio-rng.c @@ -21,6 +21,7 @@ #include #include #include +#include #include /* The host will fill any buffer we give it with sweet, sweet randomness. We diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c index a035ae39a359..0d328b59568d 100644 --- a/drivers/char/virtio_console.c +++ b/drivers/char/virtio_console.c @@ -31,6 +31,7 @@ #include #include #include +#include #include #include "hvc_console.h" diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index fbf04a553f5a..5c498d2b043f 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -22,6 +22,7 @@ #include #include #include +#include #include #include #include diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 39789232646d..200c22f55130 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -19,6 +19,7 @@ */ //#define DEBUG #include +#include #include #include #include diff --git a/include/linux/virtio_9p.h b/include/linux/virtio_9p.h index b3c4a60ceeb3..ea7226a45acb 100644 --- a/include/linux/virtio_9p.h +++ b/include/linux/virtio_9p.h @@ -4,8 +4,6 @@ * compatible drivers/servers. */ #include -/* The ID for virtio console */ -#define VIRTIO_ID_9P 9 /* Maximum number of virtio channels per partition (1 for now) */ #define MAX_9P_CHAN 1 diff --git a/include/linux/virtio_balloon.h b/include/linux/virtio_balloon.h index 8726ff77763e..09d730085060 100644 --- a/include/linux/virtio_balloon.h +++ b/include/linux/virtio_balloon.h @@ -4,9 +4,6 @@ * compatible drivers/servers. */ #include -/* The ID for virtio_balloon */ -#define VIRTIO_ID_BALLOON 5 - /* The feature bitmap for virtio balloon */ #define VIRTIO_BALLOON_F_MUST_TELL_HOST 0 /* Tell before reclaiming pages */ diff --git a/include/linux/virtio_blk.h b/include/linux/virtio_blk.h index 8dab9f2b8832..25fbabfa90d4 100644 --- a/include/linux/virtio_blk.h +++ b/include/linux/virtio_blk.h @@ -5,9 +5,6 @@ #include #include -/* The ID for virtio_block */ -#define VIRTIO_ID_BLOCK 2 - /* Feature bits */ #define VIRTIO_BLK_F_BARRIER 0 /* Does host support barriers? */ #define VIRTIO_BLK_F_SIZE_MAX 1 /* Indicates maximum segment size */ diff --git a/include/linux/virtio_console.h b/include/linux/virtio_console.h index dc161115ae35..b5f519806014 100644 --- a/include/linux/virtio_console.h +++ b/include/linux/virtio_console.h @@ -5,9 +5,6 @@ /* This header, excluding the #ifdef __KERNEL__ part, is BSD licensed so * anyone can use the definitions to implement compatible drivers/servers. */ -/* The ID for virtio console */ -#define VIRTIO_ID_CONSOLE 3 - /* Feature bits */ #define VIRTIO_CONSOLE_F_SIZE 0 /* Does host provide console size? */ diff --git a/include/linux/virtio_ids.h b/include/linux/virtio_ids.h new file mode 100644 index 000000000000..06660c0a78d7 --- /dev/null +++ b/include/linux/virtio_ids.h @@ -0,0 +1,17 @@ +#ifndef _LINUX_VIRTIO_IDS_H +#define _LINUX_VIRTIO_IDS_H +/* + * Virtio IDs + * + * This header is BSD licensed so anyone can use the definitions to implement + * compatible drivers/servers. + */ + +#define VIRTIO_ID_NET 1 /* virtio net */ +#define VIRTIO_ID_BLOCK 2 /* virtio block */ +#define VIRTIO_ID_CONSOLE 3 /* virtio console */ +#define VIRTIO_ID_RNG 4 /* virtio ring */ +#define VIRTIO_ID_BALLOON 5 /* virtio balloon */ +#define VIRTIO_ID_9P 9 /* 9p virtio console */ + +#endif /* _LINUX_VIRTIO_IDS_H */ diff --git a/include/linux/virtio_net.h b/include/linux/virtio_net.h index d8dd539c9f48..1f41734bbb77 100644 --- a/include/linux/virtio_net.h +++ b/include/linux/virtio_net.h @@ -6,9 +6,6 @@ #include #include -/* The ID for virtio_net */ -#define VIRTIO_ID_NET 1 - /* The feature bitmap for virtio net */ #define VIRTIO_NET_F_CSUM 0 /* Host handles pkts w/ partial csum */ #define VIRTIO_NET_F_GUEST_CSUM 1 /* Guest handles pkts w/ partial csum */ diff --git a/include/linux/virtio_rng.h b/include/linux/virtio_rng.h index 1a85dab8a940..48121c3c434b 100644 --- a/include/linux/virtio_rng.h +++ b/include/linux/virtio_rng.h @@ -4,7 +4,4 @@ * compatible drivers/servers. */ #include -/* The ID for virtio_rng */ -#define VIRTIO_ID_RNG 4 - #endif /* _LINUX_VIRTIO_RNG_H */ diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c index ea1e3daabefe..b2e07f0dd298 100644 --- a/net/9p/trans_virtio.c +++ b/net/9p/trans_virtio.c @@ -43,6 +43,7 @@ #include #include #include +#include #include #define VIRTQUEUE_NUM 128 -- cgit v1.2.3 From f1b0ef062602713c2c7cfa12362d5d90ed01c5f6 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 17 Sep 2009 19:57:42 +0200 Subject: virtio_blk: add support for cache flush Recent qemu has added a VIRTIO_BLK_F_FLUSH flag to advertise that the virtual disk has a volatile write cache that needs to be flushed. In case we see this feature implement tell the Linux block layer about the fact and use the new VIRTIO_BLK_T_FLUSH to flush the cache when required. This allows for an correct and simple implementation of write barriers. Signed-off-by: Christoph Hellwig Signed-off-by: Rusty Russell --- drivers/block/virtio_blk.c | 30 +++++++++++++++++++++++++----- include/linux/virtio_blk.h | 15 +++++++++++++++ 2 files changed, 40 insertions(+), 5 deletions(-) (limited to 'include') diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 73de7532fcf5..3d5fe97569c7 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -92,15 +92,26 @@ static bool do_req(struct request_queue *q, struct virtio_blk *vblk, return false; vbr->req = req; - if (blk_fs_request(vbr->req)) { + switch (req->cmd_type) { + case REQ_TYPE_FS: vbr->out_hdr.type = 0; vbr->out_hdr.sector = blk_rq_pos(vbr->req); vbr->out_hdr.ioprio = req_get_ioprio(vbr->req); - } else if (blk_pc_request(vbr->req)) { + break; + case REQ_TYPE_BLOCK_PC: vbr->out_hdr.type = VIRTIO_BLK_T_SCSI_CMD; vbr->out_hdr.sector = 0; vbr->out_hdr.ioprio = req_get_ioprio(vbr->req); - } else { + break; + case REQ_TYPE_LINUX_BLOCK: + if (req->cmd[0] == REQ_LB_OP_FLUSH) { + vbr->out_hdr.type = VIRTIO_BLK_T_FLUSH; + vbr->out_hdr.sector = 0; + vbr->out_hdr.ioprio = req_get_ioprio(vbr->req); + break; + } + /*FALLTHRU*/ + default: /* We don't put anything else in the queue. */ BUG(); } @@ -200,6 +211,12 @@ out: return err; } +static void virtblk_prepare_flush(struct request_queue *q, struct request *req) +{ + req->cmd_type = REQ_TYPE_LINUX_BLOCK; + req->cmd[0] = REQ_LB_OP_FLUSH; +} + static int virtblk_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd, unsigned long data) { @@ -338,7 +355,10 @@ static int __devinit virtblk_probe(struct virtio_device *vdev) index++; /* If barriers are supported, tell block layer that queue is ordered */ - if (virtio_has_feature(vdev, VIRTIO_BLK_F_BARRIER)) + if (virtio_has_feature(vdev, VIRTIO_BLK_F_FLUSH)) + blk_queue_ordered(vblk->disk->queue, QUEUE_ORDERED_DRAIN_FLUSH, + virtblk_prepare_flush); + else if (virtio_has_feature(vdev, VIRTIO_BLK_F_BARRIER)) blk_queue_ordered(vblk->disk->queue, QUEUE_ORDERED_TAG, NULL); /* If disk is read-only in the host, the guest should obey */ @@ -425,7 +445,7 @@ static struct virtio_device_id id_table[] = { static unsigned int features[] = { VIRTIO_BLK_F_BARRIER, VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX, VIRTIO_BLK_F_GEOMETRY, VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE, - VIRTIO_BLK_F_SCSI, VIRTIO_BLK_F_IDENTIFY + VIRTIO_BLK_F_SCSI, VIRTIO_BLK_F_IDENTIFY, VIRTIO_BLK_F_FLUSH }; /* diff --git a/include/linux/virtio_blk.h b/include/linux/virtio_blk.h index 25fbabfa90d4..15cb666581d7 100644 --- a/include/linux/virtio_blk.h +++ b/include/linux/virtio_blk.h @@ -14,6 +14,7 @@ #define VIRTIO_BLK_F_BLK_SIZE 6 /* Block size of disk is available*/ #define VIRTIO_BLK_F_SCSI 7 /* Supports scsi command passthru */ #define VIRTIO_BLK_F_IDENTIFY 8 /* ATA IDENTIFY supported */ +#define VIRTIO_BLK_F_FLUSH 9 /* Cache flush command support */ #define VIRTIO_BLK_ID_BYTES (sizeof(__u16[256])) /* IDENTIFY DATA */ @@ -35,6 +36,17 @@ struct virtio_blk_config { __u8 identify[VIRTIO_BLK_ID_BYTES]; } __attribute__((packed)); +/* + * Command types + * + * Usage is a bit tricky as some bits are used as flags and some are not. + * + * Rules: + * VIRTIO_BLK_T_OUT may be combined with VIRTIO_BLK_T_SCSI_CMD or + * VIRTIO_BLK_T_BARRIER. VIRTIO_BLK_T_FLUSH is a command of its own + * and may not be combined with any of the other flags. + */ + /* These two define direction. */ #define VIRTIO_BLK_T_IN 0 #define VIRTIO_BLK_T_OUT 1 @@ -42,6 +54,9 @@ struct virtio_blk_config { /* This bit says it's a scsi command, not an actual read or write. */ #define VIRTIO_BLK_T_SCSI_CMD 2 +/* Cache flush command */ +#define VIRTIO_BLK_T_FLUSH 4 + /* Barrier before this op. */ #define VIRTIO_BLK_T_BARRIER 0x80000000 -- cgit v1.2.3