linux_dsm_epyc7002/drivers/usb/gadget/function/storage_common.h
Alan Stern 225785aec7 USB: f_mass_storage: improve memory barriers and synchronization
This patch reworks the way f_mass_storage.c handles memory barriers
and synchronization:

	The driver now uses a wait_queue instead of doing its own
	task-state manipulations (even though only one task will ever
	use the wait_queue).

	The thread_wakeup_needed variable is removed.  It was only a
	source of trouble; although it was what the driver tested to
	see whether it should wake up, what we really wanted to see
	was whether a USB transfer had completed.

	All the explicit memory barriers scattered throughout the
	driver are replaced by a few calls to smp_load_acquire() and
	smp_store_release().

	The inreq_busy and outreq_busy fields are removed.  In their
	place, the driver keeps track of the current I/O direction by
	splitting BUF_STATE_BUSY into two states: BUF_STATE_SENDING
	and BUF_STATE_RECEIVING.

	The buffer states are no longer protected by a lock.  Mutual
	exclusion isn't needed; the state is changed only by the
	driver's main thread when it owns the buffer, and only by the
	request completion routine when the gadget core owns the buffer.

	The do_write() and throw_away_data() routines were reorganized
	to make efficient use of the new sleeping mechanism.  This
	resulted in the removal of one indentation level in those
	routines, making the patch appear to be more more complicated
	than it really is.

	In a few places, the driver allowed itself to be frozen although
	it really shouldn't have (in the middle of executing a SCSI
	command).  Those places have been fixed.

	The logic in the exception handler for aborting transfers and
	waiting for them to stop has been simplified.

Tested-by: Thinh Nguyen <thinhn@synopsys.com>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2017-05-16 10:38:33 +03:00

228 lines
6.5 KiB
C

#ifndef USB_STORAGE_COMMON_H
#define USB_STORAGE_COMMON_H
#include <linux/device.h>
#include <linux/usb/storage.h>
#include <scsi/scsi.h>
#include <asm/unaligned.h>
#ifndef DEBUG
#undef VERBOSE_DEBUG
#undef DUMP_MSGS
#endif /* !DEBUG */
#ifdef VERBOSE_DEBUG
#define VLDBG LDBG
#else
#define VLDBG(lun, fmt, args...) do { } while (0)
#endif /* VERBOSE_DEBUG */
#define _LMSG(func, lun, fmt, args...) \
do { \
if ((lun)->name_pfx && *(lun)->name_pfx) \
func("%s/%s: " fmt, *(lun)->name_pfx, \
(lun)->name, ## args); \
else \
func("%s: " fmt, (lun)->name, ## args); \
} while (0)
#define LDBG(lun, fmt, args...) _LMSG(pr_debug, lun, fmt, ## args)
#define LERROR(lun, fmt, args...) _LMSG(pr_err, lun, fmt, ## args)
#define LWARN(lun, fmt, args...) _LMSG(pr_warn, lun, fmt, ## args)
#define LINFO(lun, fmt, args...) _LMSG(pr_info, lun, fmt, ## args)
#ifdef DUMP_MSGS
# define dump_msg(fsg, /* const char * */ label, \
/* const u8 * */ buf, /* unsigned */ length) \
do { \
if (length < 512) { \
DBG(fsg, "%s, length %u:\n", label, length); \
print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, \
16, 1, buf, length, 0); \
} \
} while (0)
# define dump_cdb(fsg) do { } while (0)
#else
# define dump_msg(fsg, /* const char * */ label, \
/* const u8 * */ buf, /* unsigned */ length) do { } while (0)
# ifdef VERBOSE_DEBUG
# define dump_cdb(fsg) \
print_hex_dump(KERN_DEBUG, "SCSI CDB: ", DUMP_PREFIX_NONE, \
16, 1, (fsg)->cmnd, (fsg)->cmnd_size, 0) \
# else
# define dump_cdb(fsg) do { } while (0)
# endif /* VERBOSE_DEBUG */
#endif /* DUMP_MSGS */
/* Length of a SCSI Command Data Block */
#define MAX_COMMAND_SIZE 16
/* SCSI Sense Key/Additional Sense Code/ASC Qualifier values */
#define SS_NO_SENSE 0
#define SS_COMMUNICATION_FAILURE 0x040800
#define SS_INVALID_COMMAND 0x052000
#define SS_INVALID_FIELD_IN_CDB 0x052400
#define SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE 0x052100
#define SS_LOGICAL_UNIT_NOT_SUPPORTED 0x052500
#define SS_MEDIUM_NOT_PRESENT 0x023a00
#define SS_MEDIUM_REMOVAL_PREVENTED 0x055302
#define SS_NOT_READY_TO_READY_TRANSITION 0x062800
#define SS_RESET_OCCURRED 0x062900
#define SS_SAVING_PARAMETERS_NOT_SUPPORTED 0x053900
#define SS_UNRECOVERED_READ_ERROR 0x031100
#define SS_WRITE_ERROR 0x030c02
#define SS_WRITE_PROTECTED 0x072700
#define SK(x) ((u8) ((x) >> 16)) /* Sense Key byte, etc. */
#define ASC(x) ((u8) ((x) >> 8))
#define ASCQ(x) ((u8) (x))
/*
* Vendor (8 chars), product (16 chars), release (4 hexadecimal digits) and NUL
* byte
*/
#define INQUIRY_STRING_LEN ((size_t) (8 + 16 + 4 + 1))
struct fsg_lun {
struct file *filp;
loff_t file_length;
loff_t num_sectors;
unsigned int initially_ro:1;
unsigned int ro:1;
unsigned int removable:1;
unsigned int cdrom:1;
unsigned int prevent_medium_removal:1;
unsigned int registered:1;
unsigned int info_valid:1;
unsigned int nofua:1;
u32 sense_data;
u32 sense_data_info;
u32 unit_attention_data;
unsigned int blkbits; /* Bits of logical block size
of bound block device */
unsigned int blksize; /* logical block size of bound block device */
struct device dev;
const char *name; /* "lun.name" */
const char **name_pfx; /* "function.name" */
char inquiry_string[INQUIRY_STRING_LEN];
};
static inline bool fsg_lun_is_open(struct fsg_lun *curlun)
{
return curlun->filp != NULL;
}
/* Default size of buffer length. */
#define FSG_BUFLEN ((u32)16384)
/* Maximal number of LUNs supported in mass storage function */
#define FSG_MAX_LUNS 16
enum fsg_buffer_state {
BUF_STATE_SENDING = -2,
BUF_STATE_RECEIVING,
BUF_STATE_EMPTY = 0,
BUF_STATE_FULL
};
struct fsg_buffhd {
void *buf;
enum fsg_buffer_state state;
struct fsg_buffhd *next;
/*
* The NetChip 2280 is faster, and handles some protocol faults
* better, if we don't submit any short bulk-out read requests.
* So we will record the intended request length here.
*/
unsigned int bulk_out_intended_length;
struct usb_request *inreq;
struct usb_request *outreq;
};
enum fsg_state {
FSG_STATE_NORMAL,
FSG_STATE_ABORT_BULK_OUT,
FSG_STATE_PROTOCOL_RESET,
FSG_STATE_CONFIG_CHANGE,
FSG_STATE_EXIT,
FSG_STATE_TERMINATED
};
enum data_direction {
DATA_DIR_UNKNOWN = 0,
DATA_DIR_FROM_HOST,
DATA_DIR_TO_HOST,
DATA_DIR_NONE
};
static inline u32 get_unaligned_be24(u8 *buf)
{
return 0xffffff & (u32) get_unaligned_be32(buf - 1);
}
static inline struct fsg_lun *fsg_lun_from_dev(struct device *dev)
{
return container_of(dev, struct fsg_lun, dev);
}
enum {
FSG_STRING_INTERFACE
};
extern struct usb_interface_descriptor fsg_intf_desc;
extern struct usb_endpoint_descriptor fsg_fs_bulk_in_desc;
extern struct usb_endpoint_descriptor fsg_fs_bulk_out_desc;
extern struct usb_descriptor_header *fsg_fs_function[];
extern struct usb_endpoint_descriptor fsg_hs_bulk_in_desc;
extern struct usb_endpoint_descriptor fsg_hs_bulk_out_desc;
extern struct usb_descriptor_header *fsg_hs_function[];
extern struct usb_endpoint_descriptor fsg_ss_bulk_in_desc;
extern struct usb_ss_ep_comp_descriptor fsg_ss_bulk_in_comp_desc;
extern struct usb_endpoint_descriptor fsg_ss_bulk_out_desc;
extern struct usb_ss_ep_comp_descriptor fsg_ss_bulk_out_comp_desc;
extern struct usb_descriptor_header *fsg_ss_function[];
void fsg_lun_close(struct fsg_lun *curlun);
int fsg_lun_open(struct fsg_lun *curlun, const char *filename);
int fsg_lun_fsync_sub(struct fsg_lun *curlun);
void store_cdrom_address(u8 *dest, int msf, u32 addr);
ssize_t fsg_show_ro(struct fsg_lun *curlun, char *buf);
ssize_t fsg_show_nofua(struct fsg_lun *curlun, char *buf);
ssize_t fsg_show_file(struct fsg_lun *curlun, struct rw_semaphore *filesem,
char *buf);
ssize_t fsg_show_inquiry_string(struct fsg_lun *curlun, char *buf);
ssize_t fsg_show_cdrom(struct fsg_lun *curlun, char *buf);
ssize_t fsg_show_removable(struct fsg_lun *curlun, char *buf);
ssize_t fsg_store_ro(struct fsg_lun *curlun, struct rw_semaphore *filesem,
const char *buf, size_t count);
ssize_t fsg_store_nofua(struct fsg_lun *curlun, const char *buf, size_t count);
ssize_t fsg_store_file(struct fsg_lun *curlun, struct rw_semaphore *filesem,
const char *buf, size_t count);
ssize_t fsg_store_cdrom(struct fsg_lun *curlun, struct rw_semaphore *filesem,
const char *buf, size_t count);
ssize_t fsg_store_removable(struct fsg_lun *curlun, const char *buf,
size_t count);
ssize_t fsg_store_inquiry_string(struct fsg_lun *curlun, const char *buf,
size_t count);
#endif /* USB_STORAGE_COMMON_H */