From 8f36b3b4e1b58dca7d05e1579019230437e55d43 Mon Sep 17 00:00:00 2001 From: Shuah Khan Date: Tue, 23 Aug 2022 18:24:56 -0600 Subject: [PATCH] usbip: add USBIP_URB_* URB transfer flags USBIP driver packs URB transfer flags in network packets that are exchanged between Server (usbip_host) and Client (vhci_hcd). URB_* flags are internal to kernel and could change. Where as USBIP URB flags exchanged in network packets are USBIP user API must not change. Add USBIP_URB* flags to make this an explicit API and change the client and server to map them. Details as follows: Client tx path (USBIP_CMD_SUBMIT): - Maps URB_* to USBIP_URB_* when it sends USBIP_CMD_SUBMIT packet. Server rx path (USBIP_CMD_SUBMIT): - Maps USBIP_URB_* to URB_* when it receives USBIP_CMD_SUBMIT packet. Flags aren't included in USBIP_CMD_UNLINK and USBIP_RET_SUBMIT packets and no special handling is needed for them in the following cases: - Server rx path (USBIP_CMD_UNLINK) - Client rx path & Server tx path (USBIP_RET_SUBMIT) Update protocol documentation to reflect the change. Suggested-by: Hongren Zenithal Zheng Suggested-by: Alan Stern Signed-off-by: Shuah Khan Link: https://lore.kernel.org/r/20220824002456.94605-1-skhan@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- Documentation/usb/usbip_protocol.rst | 13 ++-- drivers/usb/usbip/stub_rx.c | 4 +- drivers/usb/usbip/usbip_common.c | 91 +++++++++++++++++++++++++++- include/uapi/linux/usbip.h | 26 ++++++++ 4 files changed, 122 insertions(+), 12 deletions(-) diff --git a/Documentation/usb/usbip_protocol.rst b/Documentation/usb/usbip_protocol.rst index 0b8541fda4d8..adc158967cc6 100644 --- a/Documentation/usb/usbip_protocol.rst +++ b/Documentation/usb/usbip_protocol.rst @@ -340,13 +340,12 @@ USBIP_CMD_SUBMIT: | 0 | 20 | usbip_header_basic, 'command' shall be 0x00000001 | +-----------+--------+---------------------------------------------------+ | 0x14 | 4 | transfer_flags: possible values depend on the | -| | | URB transfer_flags (refer to URB doc in | -| | | Documentation/driver-api/usb/URB.rst) | -| | | but with URB_NO_TRANSFER_DMA_MAP masked. Refer to | -| | | function usbip_pack_cmd_submit and function | -| | | tweak_transfer_flags in drivers/usb/usbip/ | -| | | usbip_common.c. The following fields may also ref | -| | | to function usbip_pack_cmd_submit and URB doc | +| | | USBIP_URB transfer_flags. | +| | | Refer to include/uapi/linux/usbip.h and | +| | | Documentation/driver-api/usb/URB.rst. | +| | | Refer to usbip_pack_cmd_submit() and | +| | | tweak_transfer_flags() in drivers/usb/usbip/ | +| | | usbip_common.c. | +-----------+--------+---------------------------------------------------+ | 0x18 | 4 | transfer_buffer_length: | | | | use URB transfer_buffer_length | diff --git a/drivers/usb/usbip/stub_rx.c b/drivers/usb/usbip/stub_rx.c index 5dd41e8215e0..fc01b31bbb87 100644 --- a/drivers/usb/usbip/stub_rx.c +++ b/drivers/usb/usbip/stub_rx.c @@ -464,7 +464,7 @@ static void stub_recv_cmd_submit(struct stub_device *sdev, int nents; int num_urbs = 1; int pipe = get_pipe(sdev, pdu); - int use_sg = pdu->u.cmd_submit.transfer_flags & URB_DMA_MAP_SG; + int use_sg = pdu->u.cmd_submit.transfer_flags & USBIP_URB_DMA_MAP_SG; int support_sg = 1; int np = 0; int ret, i; @@ -514,7 +514,7 @@ static void stub_recv_cmd_submit(struct stub_device *sdev, num_urbs = nents; priv->completed_urbs = 0; pdu->u.cmd_submit.transfer_flags &= - ~URB_DMA_MAP_SG; + ~USBIP_URB_DMA_MAP_SG; } } else { buffer = kzalloc(buf_len, GFP_KERNEL); diff --git a/drivers/usb/usbip/usbip_common.c b/drivers/usb/usbip/usbip_common.c index 2ab99244bc31..053a2bca4c47 100644 --- a/drivers/usb/usbip/usbip_common.c +++ b/drivers/usb/usbip/usbip_common.c @@ -344,6 +344,91 @@ static unsigned int tweak_transfer_flags(unsigned int flags) return flags; } +/* + * USBIP driver packs URB transfer flags in PDUs that are exchanged + * between Server (usbip_host) and Client (vhci_hcd). URB_* flags + * are internal to kernel and could change. Where as USBIP URB flags + * exchanged in PDUs are USBIP user API must not change. + * + * USBIP_URB* flags are exported as explicit API and client and server + * do mapping from kernel flags to USBIP_URB*. Details as follows: + * + * Client tx path (USBIP_CMD_SUBMIT): + * - Maps URB_* to USBIP_URB_* when it sends USBIP_CMD_SUBMIT packet. + * + * Server rx path (USBIP_CMD_SUBMIT): + * - Maps USBIP_URB_* to URB_* when it receives USBIP_CMD_SUBMIT packet. + * + * Flags aren't included in USBIP_CMD_UNLINK and USBIP_RET_SUBMIT packets + * and no special handling is needed for them in the following cases: + * - Server rx path (USBIP_CMD_UNLINK) + * - Client rx path & Server tx path (USBIP_RET_SUBMIT) + * + * Code paths: + * usbip_pack_pdu() is the common routine that handles packing pdu from + * urb and unpack pdu to an urb. + * + * usbip_pack_cmd_submit() and usbip_pack_ret_submit() handle + * USBIP_CMD_SUBMIT and USBIP_RET_SUBMIT respectively. + * + * usbip_map_urb_to_usbip() and usbip_map_usbip_to_urb() are used + * by usbip_pack_cmd_submit() and usbip_pack_ret_submit() to map + * flags. + */ + +struct urb_to_usbip_flags { + u32 urb_flag; + u32 usbip_flag; +}; + +#define NUM_USBIP_FLAGS 17 + +static const struct urb_to_usbip_flags flag_map[NUM_USBIP_FLAGS] = { + {URB_SHORT_NOT_OK, USBIP_URB_SHORT_NOT_OK}, + {URB_ISO_ASAP, USBIP_URB_ISO_ASAP}, + {URB_NO_TRANSFER_DMA_MAP, USBIP_URB_NO_TRANSFER_DMA_MAP}, + {URB_ZERO_PACKET, USBIP_URB_ZERO_PACKET}, + {URB_NO_INTERRUPT, USBIP_URB_NO_INTERRUPT}, + {URB_FREE_BUFFER, USBIP_URB_FREE_BUFFER}, + {URB_DIR_IN, USBIP_URB_DIR_IN}, + {URB_DIR_OUT, USBIP_URB_DIR_OUT}, + {URB_DIR_MASK, USBIP_URB_DIR_MASK}, + {URB_DMA_MAP_SINGLE, USBIP_URB_DMA_MAP_SINGLE}, + {URB_DMA_MAP_PAGE, USBIP_URB_DMA_MAP_PAGE}, + {URB_DMA_MAP_SG, USBIP_URB_DMA_MAP_SG}, + {URB_MAP_LOCAL, USBIP_URB_MAP_LOCAL}, + {URB_SETUP_MAP_SINGLE, USBIP_URB_SETUP_MAP_SINGLE}, + {URB_SETUP_MAP_LOCAL, USBIP_URB_SETUP_MAP_LOCAL}, + {URB_DMA_SG_COMBINED, USBIP_URB_DMA_SG_COMBINED}, + {URB_ALIGNED_TEMP_BUFFER, USBIP_URB_ALIGNED_TEMP_BUFFER}, +}; + +static unsigned int urb_to_usbip(unsigned int flags) +{ + unsigned int map_flags = 0; + int loop; + + for (loop = 0; loop < NUM_USBIP_FLAGS; loop++) { + if (flags & flag_map[loop].urb_flag) + map_flags |= flag_map[loop].usbip_flag; + } + + return map_flags; +} + +static unsigned int usbip_to_urb(unsigned int flags) +{ + unsigned int map_flags = 0; + int loop; + + for (loop = 0; loop < NUM_USBIP_FLAGS; loop++) { + if (flags & flag_map[loop].usbip_flag) + map_flags |= flag_map[loop].urb_flag; + } + + return map_flags; +} + static void usbip_pack_cmd_submit(struct usbip_header *pdu, struct urb *urb, int pack) { @@ -354,14 +439,14 @@ static void usbip_pack_cmd_submit(struct usbip_header *pdu, struct urb *urb, * will be discussed when usbip is ported to other operating systems. */ if (pack) { - spdu->transfer_flags = - tweak_transfer_flags(urb->transfer_flags); + /* map after tweaking the urb flags */ + spdu->transfer_flags = urb_to_usbip(tweak_transfer_flags(urb->transfer_flags)); spdu->transfer_buffer_length = urb->transfer_buffer_length; spdu->start_frame = urb->start_frame; spdu->number_of_packets = urb->number_of_packets; spdu->interval = urb->interval; } else { - urb->transfer_flags = spdu->transfer_flags; + urb->transfer_flags = usbip_to_urb(spdu->transfer_flags); urb->transfer_buffer_length = spdu->transfer_buffer_length; urb->start_frame = spdu->start_frame; urb->number_of_packets = spdu->number_of_packets; diff --git a/include/uapi/linux/usbip.h b/include/uapi/linux/usbip.h index fd393d908d8a..e4421ad55b2e 100644 --- a/include/uapi/linux/usbip.h +++ b/include/uapi/linux/usbip.h @@ -24,4 +24,30 @@ enum usbip_device_status { VDEV_ST_USED, VDEV_ST_ERROR }; + +/* USB URB Transfer flags: + * + * USBIP server and client (vchi) pack URBs in TCP packets. The following + * are the transfer type defines used in USBIP protocol. + */ + +#define USBIP_URB_SHORT_NOT_OK 0x0001 +#define USBIP_URB_ISO_ASAP 0x0002 +#define USBIP_URB_NO_TRANSFER_DMA_MAP 0x0004 +#define USBIP_URB_ZERO_PACKET 0x0040 +#define USBIP_URB_NO_INTERRUPT 0x0080 +#define USBIP_URB_FREE_BUFFER 0x0100 +#define USBIP_URB_DIR_IN 0x0200 +#define USBIP_URB_DIR_OUT 0 +#define USBIP_URB_DIR_MASK USBIP_URB_DIR_IN + +#define USBIP_URB_DMA_MAP_SINGLE 0x00010000 +#define USBIP_URB_DMA_MAP_PAGE 0x00020000 +#define USBIP_URB_DMA_MAP_SG 0x00040000 +#define USBIP_URB_MAP_LOCAL 0x00080000 +#define USBIP_URB_SETUP_MAP_SINGLE 0x00100000 +#define USBIP_URB_SETUP_MAP_LOCAL 0x00200000 +#define USBIP_URB_DMA_SG_COMBINED 0x00400000 +#define USBIP_URB_ALIGNED_TEMP_BUFFER 0x00800000 + #endif /* _UAPI_LINUX_USBIP_H */