diff options
Diffstat (limited to 'include/linux/lguest_launcher.h')
-rw-r--r-- | include/linux/lguest_launcher.h | 36 |
1 files changed, 1 insertions, 35 deletions
diff --git a/include/linux/lguest_launcher.h b/include/linux/lguest_launcher.h index b6603f3fbff8..5ec04a225e4f 100644 --- a/include/linux/lguest_launcher.h +++ b/include/linux/lguest_launcher.h @@ -10,40 +10,6 @@ /* How many devices? Assume each one wants up to two dma arrays per device. */ #define LGUEST_MAX_DEVICES (LGUEST_MAX_DMA/2) -/*D:200 - * Lguest I/O - * - * The lguest I/O mechanism is the only way Guests can talk to devices. There - * are two hypercalls involved: SEND_DMA for output and BIND_DMA for input. In - * each case, "struct lguest_dma" describes the buffer: this contains 16 - * addr/len pairs, and if there are fewer buffer elements the len array is - * terminated with a 0. - * - * I/O is organized by keys: BIND_DMA attaches buffers to a particular key, and - * SEND_DMA transfers to buffers bound to particular key. By convention, keys - * correspond to a physical address within the device's page. This means that - * devices will never accidentally end up with the same keys, and allows the - * Host use The Futex Trick (as we'll see later in our journey). - * - * SEND_DMA simply indicates a key to send to, and the physical address of the - * "struct lguest_dma" to send. The Host will write the number of bytes - * transferred into the "struct lguest_dma"'s used_len member. - * - * BIND_DMA indicates a key to bind to, a pointer to an array of "struct - * lguest_dma"s ready for receiving, the size of that array, and an interrupt - * to trigger when data is received. The Host will only allow transfers into - * buffers with a used_len of zero: it then sets used_len to the number of - * bytes transferred and triggers the interrupt for the Guest to process the - * new input. */ -struct lguest_dma -{ - /* 0 if free to be used, filled by the Host. */ - __u32 used_len; - __u16 len[LGUEST_MAX_DMA_SECTIONS]; - unsigned long addr[LGUEST_MAX_DMA_SECTIONS]; -}; -/*:*/ - /* Where the Host expects the Guest to SEND_DMA console output to. */ #define LGUEST_CONSOLE_DMA_KEY 0 @@ -95,7 +61,7 @@ struct lguest_device_desc { enum lguest_req { LHREQ_INITIALIZE, /* + pfnlimit, pgdir, start, pageoffset */ - LHREQ_GETDMA, /* + addr (returns &lguest_dma, irq in ->used_len) */ + LHREQ_GETDMA, /* No longer used */ LHREQ_IRQ, /* + irq */ LHREQ_BREAK, /* + on/off flag (on blocks until someone does off) */ }; |