diff options
Diffstat (limited to 'drivers/xen/xenbus/xenbus_dev_frontend.c')
| -rw-r--r-- | drivers/xen/xenbus/xenbus_dev_frontend.c | 24 |
1 files changed, 19 insertions, 5 deletions
diff --git a/drivers/xen/xenbus/xenbus_dev_frontend.c b/drivers/xen/xenbus/xenbus_dev_frontend.c index c3e201025ef0..08adc590f631 100644 --- a/drivers/xen/xenbus/xenbus_dev_frontend.c +++ b/drivers/xen/xenbus/xenbus_dev_frontend.c @@ -62,6 +62,8 @@ #include "xenbus.h" +unsigned int xb_dev_generation_id; + /* * An element of a list of outstanding transactions, for which we're * still waiting a reply. @@ -69,6 +71,7 @@ struct xenbus_transaction_holder { struct list_head list; struct xenbus_transaction handle; + unsigned int generation_id; }; /* @@ -441,6 +444,7 @@ static int xenbus_write_transaction(unsigned msg_type, rc = -ENOMEM; goto out; } + trans->generation_id = xb_dev_generation_id; list_add(&trans->list, &u->transactions); } else if (msg->hdr.tx_id != 0 && !xenbus_get_transaction(u, msg->hdr.tx_id)) @@ -449,6 +453,20 @@ static int xenbus_write_transaction(unsigned msg_type, !(msg->hdr.len == 2 && (!strcmp(msg->body, "T") || !strcmp(msg->body, "F")))) return xenbus_command_reply(u, XS_ERROR, "EINVAL"); + else if (msg_type == XS_TRANSACTION_END) { + trans = xenbus_get_transaction(u, msg->hdr.tx_id); + if (trans && trans->generation_id != xb_dev_generation_id) { + list_del(&trans->list); + kfree(trans); + if (!strcmp(msg->body, "T")) + return xenbus_command_reply(u, XS_ERROR, + "EAGAIN"); + else + return xenbus_command_reply(u, + XS_TRANSACTION_END, + "OK"); + } + } rc = xenbus_dev_request_and_reply(&msg->hdr, u); if (rc && trans) { @@ -465,7 +483,6 @@ static int xenbus_write_watch(unsigned msg_type, struct xenbus_file_priv *u) struct watch_adapter *watch; char *path, *token; int err, rc; - LIST_HEAD(staging_q); path = u->u.buffer + sizeof(u->u.msg); token = memchr(path, 0, u->u.msg.len); @@ -523,7 +540,6 @@ static ssize_t xenbus_file_write(struct file *filp, uint32_t msg_type; int rc = len; int ret; - LIST_HEAD(staging_q); /* * We're expecting usermode to be writing properly formed @@ -622,9 +638,7 @@ static int xenbus_file_open(struct inode *inode, struct file *filp) if (xen_store_evtchn == 0) return -ENOENT; - nonseekable_open(inode, filp); - - filp->f_mode &= ~FMODE_ATOMIC_POS; /* cdev-style semantics */ + stream_open(inode, filp); u = kzalloc(sizeof(*u), GFP_KERNEL); if (u == NULL) |