diff options
Diffstat (limited to 'i386/i386/io_perm.c')
| -rw-r--r-- | i386/i386/io_perm.c | 27 |
1 files changed, 22 insertions, 5 deletions
diff --git a/i386/i386/io_perm.c b/i386/i386/io_perm.c index 3224fdd3..086d1d8f 100644 --- a/i386/i386/io_perm.c +++ b/i386/i386/io_perm.c @@ -67,10 +67,22 @@ #include "io_perm.h" #include "gdt.h" #include "pcb.h" + +#define PCI_CFG1_START 0xcf8 +#define PCI_CFG1_END 0xcff +#define PCI_CFG2_START 0xc000 +#define PCI_CFG2_END 0xcfff + +#define IS_IN_PROTECTED_RANGE(from, to) \ + ( ( ( from <= PCI_CFG1_END ) && ( to >= PCI_CFG1_START ) ) || \ + ( ( from <= PCI_CFG2_END ) && ( to >= PCI_CFG2_START ) ) ) + /* Our device emulation ops. See below, at the bottom of this file. */ static struct device_emulation_ops io_perm_device_emulation_ops; +/* Flag to hold PCI io cfg access lock */ +static boolean_t taken_pci_cfg = FALSE; /* The outtran which allows MIG to convert an io_perm_t object to a port representing it. */ @@ -107,17 +119,15 @@ convert_port_to_io_perm (ipc_port_t port) return io_perm; } -#if TODO_REMOVE_ME -/* TODO. Fix this comment. */ /* The destructor which is called when the last send right to a port representing an io_perm_t object vanishes. */ void io_perm_deallocate (io_perm_t io_perm) { - /* TODO. Is there anything to deallocate in here? I don't think so, as we - don't allocate anything in `convert_port_to_io_perm'. */ + /* We need to check if the io_perm was a PCI cfg one and release it */ + if (IS_IN_PROTECTED_RANGE(io_perm->from, io_perm->to)) + taken_pci_cfg = FALSE; } -#endif /* Our ``no senders'' handling routine. Deallocate the object. */ static @@ -185,6 +195,10 @@ i386_io_perm_create (const ipc_port_t master_port, io_port_t from, io_port_t to, if (from > to) return KERN_INVALID_ARGUMENT; + /* Only one process may take a range that includes PCI cfg registers */ + if (taken_pci_cfg && IS_IN_PROTECTED_RANGE(from, to)) + return KERN_PROTECTION_FAILURE; + io_perm_t io_perm; io_perm = (io_perm_t) kalloc (sizeof *io_perm); @@ -216,6 +230,9 @@ i386_io_perm_create (const ipc_port_t master_port, io_port_t from, io_port_t to, *new = io_perm; + if (IS_IN_PROTECTED_RANGE(from, to)) + taken_pci_cfg = TRUE; + return KERN_SUCCESS; } |