| Message ID | 1306333427-26186-2-git-send-email-levinsasha928@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
* Sasha Levin <levinsasha928@gmail.com> wrote: > +u16 ioport__find_free_range(void) > +{ > + static u16 cur_loc; Please don't put statics inside function bodies! (even if they are only used within a single function) I had to look three times to discover that it's really a global variable. These should be where other global variables are, or should be put before the function, in plain sight. Also, if you do that i'd suggest a more descriptive name - free_io_port_idx perhaps? > + return IOPORT_START + (cur_loc++ * IOPORT_SIZE); So this is SMP unsafe really. While ioport registrations are currently only used from initdev() functions and are thus serialized, it's not completely unfeasible that we would want to have async initcalls like the kernel does, to improve bootup/startup performance! So it would be nice to make this all SMP safe. A single mutex would suffice i suspect. Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/tools/kvm/include/kvm/ioport.h b/tools/kvm/include/kvm/ioport.h index 2a8d74d..bc7ea02 100644 --- a/tools/kvm/include/kvm/ioport.h +++ b/tools/kvm/include/kvm/ioport.h @@ -7,6 +7,9 @@ /* some ports we reserve for own use */ #define IOPORT_DBG 0xe0 +#define IOPORT_START 0x6200 +#define IOPORT_SIZE 0x400 + #define IOPORT_VESA 0xa200 #define IOPORT_VESA_SIZE 256 #define IOPORT_VIRTIO_P9 0xb200 /* Virtio 9P device */ @@ -34,6 +37,8 @@ void ioport__setup_legacy(void); void ioport__register(u16 port, struct ioport_operations *ops, int count); void ioport__register_param(u16 port, struct ioport_operations *ops, int count, void *param); +u16 ioport__find_free_range(void); + static inline u8 ioport__read8(u8 *data) { return *data; diff --git a/tools/kvm/ioport.c b/tools/kvm/ioport.c index 159d089..0db5a87 100644 --- a/tools/kvm/ioport.c +++ b/tools/kvm/ioport.c @@ -126,6 +126,13 @@ static void ioport_error(u16 port, void *data, int direction, int size, u32 coun fprintf(stderr, "IO error: %s port=%x, size=%d, count=%u\n", to_direction(direction), port, size, count); } +u16 ioport__find_free_range(void) +{ + static u16 cur_loc; + + return IOPORT_START + (cur_loc++ * IOPORT_SIZE); +} + bool kvm__emulate_io(struct kvm *kvm, u16 port, void *data, int direction, int size, u32 count) { struct ioport_operations *ops;
Add a very simple allocation of ioports. This prevents the need to coordinate ioports between different modules. Signed-off-by: Sasha Levin <levinsasha928@gmail.com> --- tools/kvm/include/kvm/ioport.h | 5 +++++ tools/kvm/ioport.c | 7 +++++++ 2 files changed, 12 insertions(+), 0 deletions(-)