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| author | Rusty Russell <rusty@rustcorp.com.au> | 2015-02-11 07:45:09 +0300 |
|---|---|---|
| committer | Rusty Russell <rusty@rustcorp.com.au> | 2015-02-11 09:17:30 +0300 |
| commit | 8ed313001a892f240269dea05d4b925cbd150492 (patch) | |
| tree | 340461d5b381ffc3b939bb6d414f20a732ff85c5 | |
| parent | 69a09dc1742ffbb3b02f3a1e03da4801e96452e9 (diff) | |
| download | linux-8ed313001a892f240269dea05d4b925cbd150492.tar.xz | |
lguest: add infrastructure for userspace to deliver a trap to the guest.
This is required for instruction emulation to move to userspace.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| -rw-r--r-- | drivers/lguest/lguest_user.c | 19 | ||||
| -rw-r--r-- | include/linux/lguest_launcher.h | 1 |
2 files changed, 20 insertions, 0 deletions
diff --git a/drivers/lguest/lguest_user.c b/drivers/lguest/lguest_user.c index dcf9efd94cf4..be996d173615 100644 --- a/drivers/lguest/lguest_user.c +++ b/drivers/lguest/lguest_user.c @@ -243,6 +243,23 @@ static int user_send_irq(struct lg_cpu *cpu, const unsigned long __user *input) return 0; } +/*L:053 + * Deliver a trap: this is used by the Launcher if it can't emulate + * an instruction. + */ +static int trap(struct lg_cpu *cpu, const unsigned long __user *input) +{ + unsigned long trapnum; + + if (get_user(trapnum, input) != 0) + return -EFAULT; + + if (!deliver_trap(cpu, trapnum)) + return -EINVAL; + + return 0; +} + /*L:040 * Once our Guest is initialized, the Launcher makes it run by reading * from /dev/lguest. @@ -487,6 +504,8 @@ static ssize_t write(struct file *file, const char __user *in, return getreg_setup(cpu, input); case LHREQ_SETREG: return setreg(cpu, input); + case LHREQ_TRAP: + return trap(cpu, input); default: return -EINVAL; } diff --git a/include/linux/lguest_launcher.h b/include/linux/lguest_launcher.h index c4451ebece47..3c402b843e03 100644 --- a/include/linux/lguest_launcher.h +++ b/include/linux/lguest_launcher.h @@ -65,6 +65,7 @@ enum lguest_req LHREQ_EVENTFD, /* + address, fd. */ LHREQ_GETREG, /* + offset within struct pt_regs (then read value). */ LHREQ_SETREG, /* + offset within struct pt_regs, value. */ + LHREQ_TRAP, /* + trap number to deliver to guest. */ }; /* |