[deliverable/linux.git] / drivers / usb / gadget / storage_common.c

/*
 * storage_common.c -- Common definitions for mass storage functionality
 *
 * Copyright (C) 2003-2008 Alan Stern
 * Copyeight (C) 2009 Samsung Electronics
 * Author: Michal Nazarewicz (m.nazarewicz@samsung.com)
 */


/*-------------------------------------------------------------------------*/


#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 LDBG(lun, fmt, args...)   dev_dbg (&(lun)->dev, fmt, ## args)
#define LERROR(lun, fmt, args...) dev_err (&(lun)->dev, fmt, ## args)
#define LWARN(lun, fmt, args...)  dev_warn(&(lun)->dev, fmt, ## args)
#define LINFO(lun, fmt, args...)  dev_info(&(lun)->dev, fmt, ## args)

#define DBG(d, fmt, args...)      dev_dbg (&(d)->gadget->dev, fmt, ## args)
#define VDBG(d, fmt, args...)     dev_vdbg(&(d)->gadget->dev, fmt, ## args)
#define ERROR(d, fmt, args...)    dev_err (&(d)->gadget->dev, fmt, ## args)
#define WARNING(d, fmt, args...)  dev_warn(&(d)->gadget->dev, fmt, ## args)
#define INFO(d, fmt, args...)     dev_info(&(d)->gadget->dev, 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 */


/*-------------------------------------------------------------------------*/

/* SCSI device types */
#define TYPE_DISK	0x00
#define TYPE_CDROM	0x05

/* USB protocol value = the transport method */
#define USB_PR_CBI	0x00		// Control/Bulk/Interrupt
#define USB_PR_CB	0x01		// Control/Bulk w/o interrupt
#define USB_PR_BULK	0x50		// Bulk-only

/* USB subclass value = the protocol encapsulation */
#define USB_SC_RBC	0x01		// Reduced Block Commands (flash)
#define USB_SC_8020	0x02		// SFF-8020i, MMC-2, ATAPI (CD-ROM)
#define USB_SC_QIC	0x03		// QIC-157 (tape)
#define USB_SC_UFI	0x04		// UFI (floppy)
#define USB_SC_8070	0x05		// SFF-8070i (removable)
#define USB_SC_SCSI	0x06		// Transparent SCSI

/* Bulk-only data structures */

/* Command Block Wrapper */
struct bulk_cb_wrap {
	__le32	Signature;		// Contains 'USBC'
	u32	Tag;			// Unique per command id
	__le32	DataTransferLength;	// Size of the data
	u8	Flags;			// Direction in bit 7
	u8	Lun;			// LUN (normally 0)
	u8	Length;			// Of the CDB, <= MAX_COMMAND_SIZE
	u8	CDB[16];		// Command Data Block
};

#define USB_BULK_CB_WRAP_LEN	31
#define USB_BULK_CB_SIG		0x43425355	// Spells out USBC
#define USB_BULK_IN_FLAG	0x80

/* Command Status Wrapper */
struct bulk_cs_wrap {
	__le32	Signature;		// Should = 'USBS'
	u32	Tag;			// Same as original command
	__le32	Residue;		// Amount not transferred
	u8	Status;			// See below
};

#define USB_BULK_CS_WRAP_LEN	13
#define USB_BULK_CS_SIG		0x53425355	// Spells out 'USBS'
#define USB_STATUS_PASS		0
#define USB_STATUS_FAIL		1
#define USB_STATUS_PHASE_ERROR	2

/* Bulk-only class specific requests */
#define USB_BULK_RESET_REQUEST		0xff
#define USB_BULK_GET_MAX_LUN_REQUEST	0xfe


/* CBI Interrupt data structure */
struct interrupt_data {
	u8	bType;
	u8	bValue;
};

#define CBI_INTERRUPT_DATA_LEN		2

/* CBI Accept Device-Specific Command request */
#define USB_CBI_ADSC_REQUEST		0x00


#define MAX_COMMAND_SIZE	16	// Length of a SCSI Command Data Block

/* SCSI commands that we recognize */
#define SC_FORMAT_UNIT			0x04
#define SC_INQUIRY			0x12
#define SC_MODE_SELECT_6		0x15
#define SC_MODE_SELECT_10		0x55
#define SC_MODE_SENSE_6			0x1a
#define SC_MODE_SENSE_10		0x5a
#define SC_PREVENT_ALLOW_MEDIUM_REMOVAL	0x1e
#define SC_READ_6			0x08
#define SC_READ_10			0x28
#define SC_READ_12			0xa8
#define SC_READ_CAPACITY		0x25
#define SC_READ_FORMAT_CAPACITIES	0x23
#define SC_READ_HEADER			0x44
#define SC_READ_TOC			0x43
#define SC_RELEASE			0x17
#define SC_REQUEST_SENSE		0x03
#define SC_RESERVE			0x16
#define SC_SEND_DIAGNOSTIC		0x1d
#define SC_START_STOP_UNIT		0x1b
#define SC_SYNCHRONIZE_CACHE		0x35
#define SC_TEST_UNIT_READY		0x00
#define SC_VERIFY			0x2f
#define SC_WRITE_6			0x0a
#define SC_WRITE_10			0x2a
#define SC_WRITE_12			0xaa

/* 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))


/*-------------------------------------------------------------------------*/


struct lun {
	struct file	*filp;
	loff_t		file_length;
	loff_t		num_sectors;

	unsigned int	ro : 1;
	unsigned int	prevent_medium_removal : 1;
	unsigned int	registered : 1;
	unsigned int	info_valid : 1;

	u32		sense_data;
	u32		sense_data_info;
	u32		unit_attention_data;

	struct device	dev;
};

#define backing_file_is_open(curlun)	((curlun)->filp != NULL)

static struct lun *dev_to_lun(struct device *dev)
{
	return container_of(dev, struct lun, dev);
}


/* Big enough to hold our biggest descriptor */
#define EP0_BUFSIZE	256
#define DELAYED_STATUS	(EP0_BUFSIZE + 999)	// An impossibly large value

/* Number of buffers we will use.  2 is enough for double-buffering */
#define NUM_BUFFERS	2

enum fsg_buffer_state {
	BUF_STATE_EMPTY = 0,
	BUF_STATE_FULL,
	BUF_STATE_BUSY
};

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;
	int				inreq_busy;
	struct usb_request		*outreq;
	int				outreq_busy;
};

enum fsg_state {
	FSG_STATE_COMMAND_PHASE = -10,		// This one isn't used anywhere
	FSG_STATE_DATA_PHASE,
	FSG_STATE_STATUS_PHASE,

	FSG_STATE_IDLE = 0,
	FSG_STATE_ABORT_BULK_OUT,
	FSG_STATE_RESET,
	FSG_STATE_INTERFACE_CHANGE,
	FSG_STATE_CONFIG_CHANGE,
	FSG_STATE_DISCONNECT,
	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);
}


/*-------------------------------------------------------------------------*/


#define STRING_MANUFACTURER	1
#define STRING_PRODUCT		2
#define STRING_SERIAL		3
#define STRING_CONFIG		4
#define STRING_INTERFACE	5


static struct usb_otg_descriptor
otg_desc = {
	.bLength =		sizeof(otg_desc),
	.bDescriptorType =	USB_DT_OTG,

	.bmAttributes =		USB_OTG_SRP,
};

/* There is only one interface. */

static struct usb_interface_descriptor
intf_desc = {
	.bLength =		sizeof intf_desc,
	.bDescriptorType =	USB_DT_INTERFACE,

	.bNumEndpoints =	2,		// Adjusted during fsg_bind()
	.bInterfaceClass =	USB_CLASS_MASS_STORAGE,
	.bInterfaceSubClass =	USB_SC_SCSI,	// Adjusted during fsg_bind()
	.bInterfaceProtocol =	USB_PR_BULK,	// Adjusted during fsg_bind()
	.iInterface =		STRING_INTERFACE,
};

/* Three full-speed endpoint descriptors: bulk-in, bulk-out,
 * and interrupt-in. */

static struct usb_endpoint_descriptor
fs_bulk_in_desc = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,

	.bEndpointAddress =	USB_DIR_IN,
	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
	/* wMaxPacketSize set by autoconfiguration */
};

static struct usb_endpoint_descriptor
fs_bulk_out_desc = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,

	.bEndpointAddress =	USB_DIR_OUT,
	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
	/* wMaxPacketSize set by autoconfiguration */
};

static struct usb_endpoint_descriptor
fs_intr_in_desc = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,

	.bEndpointAddress =	USB_DIR_IN,
	.bmAttributes =		USB_ENDPOINT_XFER_INT,
	.wMaxPacketSize =	cpu_to_le16(2),
	.bInterval =		32,	// frames -> 32 ms
};

static const struct usb_descriptor_header *fs_function[] = {
	(struct usb_descriptor_header *) &otg_desc,
	(struct usb_descriptor_header *) &intf_desc,
	(struct usb_descriptor_header *) &fs_bulk_in_desc,
	(struct usb_descriptor_header *) &fs_bulk_out_desc,
	(struct usb_descriptor_header *) &fs_intr_in_desc,
	NULL,
};
#define FS_FUNCTION_PRE_EP_ENTRIES	2


/*
 * USB 2.0 devices need to expose both high speed and full speed
 * descriptors, unless they only run at full speed.
 *
 * That means alternate endpoint descriptors (bigger packets)
 * and a "device qualifier" ... plus more construction options
 * for the config descriptor.
 */
static struct usb_endpoint_descriptor
hs_bulk_in_desc = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,

	/* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */
	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
	.wMaxPacketSize =	cpu_to_le16(512),
};

static struct usb_endpoint_descriptor
hs_bulk_out_desc = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,

	/* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */
	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
	.wMaxPacketSize =	cpu_to_le16(512),
	.bInterval =		1,	// NAK every 1 uframe
};

static struct usb_endpoint_descriptor
hs_intr_in_desc = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,

	/* bEndpointAddress copied from fs_intr_in_desc during fsg_bind() */
	.bmAttributes =		USB_ENDPOINT_XFER_INT,
	.wMaxPacketSize =	cpu_to_le16(2),
	.bInterval =		9,	// 2**(9-1) = 256 uframes -> 32 ms
};

static const struct usb_descriptor_header *hs_function[] = {
	(struct usb_descriptor_header *) &otg_desc,
	(struct usb_descriptor_header *) &intf_desc,
	(struct usb_descriptor_header *) &hs_bulk_in_desc,
	(struct usb_descriptor_header *) &hs_bulk_out_desc,
	(struct usb_descriptor_header *) &hs_intr_in_desc,
	NULL,
};
#define HS_FUNCTION_PRE_EP_ENTRIES	2

/* Maxpacket and other transfer characteristics vary by speed. */
static struct usb_endpoint_descriptor *
ep_desc(struct usb_gadget *g, struct usb_endpoint_descriptor *fs,
		struct usb_endpoint_descriptor *hs)
{
	if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
		return hs;
	return fs;
}


/* The CBI specification limits the serial string to 12 uppercase hexadecimal
 * characters. */
static char				manufacturer[64];
static char				serial[13];

/* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
static struct usb_string		strings[] = {
	{STRING_MANUFACTURER,	manufacturer},
	{STRING_PRODUCT,	longname},
	{STRING_SERIAL,		serial},
	{STRING_CONFIG,		"Self-powered"},
	{STRING_INTERFACE,	"Mass Storage"},
	{}
};

static struct usb_gadget_strings	stringtab = {
	.language	= 0x0409,		// en-us
	.strings	= strings,
};


 /*-------------------------------------------------------------------------*/

/* If the next two routines are called while the gadget is registered,
 * the caller must own fsg->filesem for writing. */

static int open_backing_file(struct lun *curlun, const char *filename)
{
	int				ro;
	struct file			*filp = NULL;
	int				rc = -EINVAL;
	struct inode			*inode = NULL;
	loff_t				size;
	loff_t				num_sectors;
	loff_t				min_sectors;

	/* R/W if we can, R/O if we must */
	ro = curlun->ro;
	if (!ro) {
		filp = filp_open(filename, O_RDWR | O_LARGEFILE, 0);
		if (-EROFS == PTR_ERR(filp))
			ro = 1;
	}
	if (ro)
		filp = filp_open(filename, O_RDONLY | O_LARGEFILE, 0);
	if (IS_ERR(filp)) {
		LINFO(curlun, "unable to open backing file: %s\n", filename);
		return PTR_ERR(filp);
	}

	if (!(filp->f_mode & FMODE_WRITE))
		ro = 1;

	if (filp->f_path.dentry)
		inode = filp->f_path.dentry->d_inode;
	if (inode && S_ISBLK(inode->i_mode)) {
		if (bdev_read_only(inode->i_bdev))
			ro = 1;
	} else if (!inode || !S_ISREG(inode->i_mode)) {
		LINFO(curlun, "invalid file type: %s\n", filename);
		goto out;
	}

	/* If we can't read the file, it's no good.
	 * If we can't write the file, use it read-only. */
	if (!filp->f_op || !(filp->f_op->read || filp->f_op->aio_read)) {
		LINFO(curlun, "file not readable: %s\n", filename);
		goto out;
	}
	if (!(filp->f_op->write || filp->f_op->aio_write))
		ro = 1;

	size = i_size_read(inode->i_mapping->host);
	if (size < 0) {
		LINFO(curlun, "unable to find file size: %s\n", filename);
		rc = (int) size;
		goto out;
	}
	num_sectors = size >> 9;	// File size in 512-byte blocks
	min_sectors = 1;
	if (mod_data.cdrom) {
		num_sectors &= ~3;	// Reduce to a multiple of 2048
		min_sectors = 300*4;	// Smallest track is 300 frames
		if (num_sectors >= 256*60*75*4) {
			num_sectors = (256*60*75 - 1) * 4;
			LINFO(curlun, "file too big: %s\n", filename);
			LINFO(curlun, "using only first %d blocks\n",
					(int) num_sectors);
		}
	}
	if (num_sectors < min_sectors) {
		LINFO(curlun, "file too small: %s\n", filename);
		rc = -ETOOSMALL;
		goto out;
	}

	get_file(filp);
	curlun->ro = ro;
	curlun->filp = filp;
	curlun->file_length = size;
	curlun->num_sectors = num_sectors;
	LDBG(curlun, "open backing file: %s\n", filename);
	rc = 0;

out:
	filp_close(filp, current->files);
	return rc;
}


static void close_backing_file(struct lun *curlun)
{
	if (curlun->filp) {
		LDBG(curlun, "close backing file\n");
		fput(curlun->filp);
		curlun->filp = NULL;
	}
}


/*-------------------------------------------------------------------------*/

/* Sync the file data, don't bother with the metadata.
 * This code was copied from fs/buffer.c:sys_fdatasync(). */
static int fsync_sub(struct lun *curlun)
{
	struct file	*filp = curlun->filp;

	if (curlun->ro || !filp)
		return 0;
	return vfs_fsync(filp, filp->f_path.dentry, 1);
}

static void store_cdrom_address(u8 *dest, int msf, u32 addr)
{
	if (msf) {
		/* Convert to Minutes-Seconds-Frames */
		addr >>= 2;		/* Convert to 2048-byte frames */
		addr += 2*75;		/* Lead-in occupies 2 seconds */
		dest[3] = addr % 75;	/* Frames */
		addr /= 75;
		dest[2] = addr % 60;	/* Seconds */
		addr /= 60;
		dest[1] = addr;		/* Minutes */
		dest[0] = 0;		/* Reserved */
	} else {
		/* Absolute sector */
		put_unaligned_be32(addr, dest);
	}
}
Commit	Line	Data
b6058d0f MN	1	/*
	2	* storage_common.c -- Common definitions for mass storage functionality
	3	*
	4	* Copyright (C) 2003-2008 Alan Stern
	5	* Copyeight (C) 2009 Samsung Electronics
	6	* Author: Michal Nazarewicz (m.nazarewicz@samsung.com)
	7	*/
	8
	9
	10
	11	/-------------------------------------------------------------------------/
	12
	13
	14	#ifndef DEBUG
	15	#undef VERBOSE_DEBUG
	16	#undef DUMP_MSGS
	17	#endif /* !DEBUG */
	18
	19	#ifdef VERBOSE_DEBUG
	20	#define VLDBG LDBG
	21	#else
	22	#define VLDBG(lun, fmt, args...) do { } while (0)
	23	#endif /* VERBOSE_DEBUG */
	24
	25	#define LDBG(lun, fmt, args...) dev_dbg (&(lun)->dev, fmt, ## args)
	26	#define LERROR(lun, fmt, args...) dev_err (&(lun)->dev, fmt, ## args)
	27	#define LWARN(lun, fmt, args...) dev_warn(&(lun)->dev, fmt, ## args)
	28	#define LINFO(lun, fmt, args...) dev_info(&(lun)->dev, fmt, ## args)
	29
	30	#define DBG(d, fmt, args...) dev_dbg (&(d)->gadget->dev, fmt, ## args)
	31	#define VDBG(d, fmt, args...) dev_vdbg(&(d)->gadget->dev, fmt, ## args)
	32	#define ERROR(d, fmt, args...) dev_err (&(d)->gadget->dev, fmt, ## args)
	33	#define WARNING(d, fmt, args...) dev_warn(&(d)->gadget->dev, fmt, ## args)
	34	#define INFO(d, fmt, args...) dev_info(&(d)->gadget->dev, fmt, ## args)
	35
	36
	37
	38	#ifdef DUMP_MSGS
	39
	40	# define dump_msg(fsg, /* const char * */ label, \
	41	/* const u8 * / buf, / unsigned */ length) do { \
	42	if (length < 512) { \
	43	DBG(fsg, "%s, length %u:\n", label, length); \
	44	print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, \
	45	16, 1, buf, length, 0); \
	46	} \
	47	} while (0)
	48
	49	# define dump_cdb(fsg) do { } while (0)
	50
	51	#else
	52
	53	# define dump_msg(fsg, /* const char * */ label, \
	54	/* const u8 * / buf, / unsigned */ length) do { } while (0)
	55
	56	# ifdef VERBOSE_DEBUG
	57
	58	#define dump_cdb(fsg) \
	59	print_hex_dump(KERN_DEBUG, "SCSI CDB: ", DUMP_PREFIX_NONE, \
	60	16, 1, (fsg)->cmnd, (fsg)->cmnd_size, 0) \
	61
	62	# else
	63
	64	# define dump_cdb(fsg) do { } while (0)
65
66	# endif /* VERBOSE_DEBUG */
67
68	#endif /* DUMP_MSGS */
69
70
71
72
73
74	/-------------------------------------------------------------------------/
75
76	/* SCSI device types */
77	#define TYPE_DISK 0x00
78	#define TYPE_CDROM 0x05
79
80	/* USB protocol value = the transport method */
81	#define USB_PR_CBI 0x00 // Control/Bulk/Interrupt
82	#define USB_PR_CB 0x01 // Control/Bulk w/o interrupt
83	#define USB_PR_BULK 0x50 // Bulk-only
84
85	/* USB subclass value = the protocol encapsulation */
86	#define USB_SC_RBC 0x01 // Reduced Block Commands (flash)
87	#define USB_SC_8020 0x02 // SFF-8020i, MMC-2, ATAPI (CD-ROM)
88	#define USB_SC_QIC 0x03 // QIC-157 (tape)
89	#define USB_SC_UFI 0x04 // UFI (floppy)
90	#define USB_SC_8070 0x05 // SFF-8070i (removable)
91	#define USB_SC_SCSI 0x06 // Transparent SCSI
92
93	/* Bulk-only data structures */
94
95	/* Command Block Wrapper */
96	struct bulk_cb_wrap {
97	__le32 Signature; // Contains 'USBC'
98	u32 Tag; // Unique per command id
99	__le32 DataTransferLength; // Size of the data
100	u8 Flags; // Direction in bit 7
101	u8 Lun; // LUN (normally 0)
102	u8 Length; // Of the CDB, <= MAX_COMMAND_SIZE
103	u8 CDB[16]; // Command Data Block
104	};
105
106	#define USB_BULK_CB_WRAP_LEN 31
107	#define USB_BULK_CB_SIG 0x43425355 // Spells out USBC
108	#define USB_BULK_IN_FLAG 0x80
109
110	/* Command Status Wrapper */
111	struct bulk_cs_wrap {
112	__le32 Signature; // Should = 'USBS'
113	u32 Tag; // Same as original command
114	__le32 Residue; // Amount not transferred
115	u8 Status; // See below
116	};
117
118	#define USB_BULK_CS_WRAP_LEN 13
119	#define USB_BULK_CS_SIG 0x53425355 // Spells out 'USBS'
120	#define USB_STATUS_PASS 0
121	#define USB_STATUS_FAIL 1
122	#define USB_STATUS_PHASE_ERROR 2
123
124	/* Bulk-only class specific requests */
125	#define USB_BULK_RESET_REQUEST 0xff
126	#define USB_BULK_GET_MAX_LUN_REQUEST 0xfe
127
128
129	/* CBI Interrupt data structure */
130	struct interrupt_data {
131	u8 bType;
132	u8 bValue;
133	};
134
135	#define CBI_INTERRUPT_DATA_LEN 2
136
137	/* CBI Accept Device-Specific Command request */
138	#define USB_CBI_ADSC_REQUEST 0x00
139
140
141	#define MAX_COMMAND_SIZE 16 // Length of a SCSI Command Data Block
142
143	/* SCSI commands that we recognize */
144	#define SC_FORMAT_UNIT 0x04
145	#define SC_INQUIRY 0x12
146	#define SC_MODE_SELECT_6 0x15
147	#define SC_MODE_SELECT_10 0x55
148	#define SC_MODE_SENSE_6 0x1a
149	#define SC_MODE_SENSE_10 0x5a
150	#define SC_PREVENT_ALLOW_MEDIUM_REMOVAL 0x1e
151	#define SC_READ_6 0x08
152	#define SC_READ_10 0x28
153	#define SC_READ_12 0xa8
154	#define SC_READ_CAPACITY 0x25
155	#define SC_READ_FORMAT_CAPACITIES 0x23
156	#define SC_READ_HEADER 0x44
157	#define SC_READ_TOC 0x43
158	#define SC_RELEASE 0x17
159	#define SC_REQUEST_SENSE 0x03
160	#define SC_RESERVE 0x16
161	#define SC_SEND_DIAGNOSTIC 0x1d
162	#define SC_START_STOP_UNIT 0x1b
163	#define SC_SYNCHRONIZE_CACHE 0x35
164	#define SC_TEST_UNIT_READY 0x00
165	#define SC_VERIFY 0x2f
166	#define SC_WRITE_6 0x0a
167	#define SC_WRITE_10 0x2a
168	#define SC_WRITE_12 0xaa
169
170	/* SCSI Sense Key/Additional Sense Code/ASC Qualifier values */
171	#define SS_NO_SENSE 0
172	#define SS_COMMUNICATION_FAILURE 0x040800
173	#define SS_INVALID_COMMAND 0x052000
174	#define SS_INVALID_FIELD_IN_CDB 0x052400
175	#define SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE 0x052100
176	#define SS_LOGICAL_UNIT_NOT_SUPPORTED 0x052500
177	#define SS_MEDIUM_NOT_PRESENT 0x023a00
178	#define SS_MEDIUM_REMOVAL_PREVENTED 0x055302
179	#define SS_NOT_READY_TO_READY_TRANSITION 0x062800
180	#define SS_RESET_OCCURRED 0x062900
181	#define SS_SAVING_PARAMETERS_NOT_SUPPORTED 0x053900
182	#define SS_UNRECOVERED_READ_ERROR 0x031100
183	#define SS_WRITE_ERROR 0x030c02
184	#define SS_WRITE_PROTECTED 0x072700
185
186	#define SK(x) ((u8) ((x) >> 16)) // Sense Key byte, etc.
187	#define ASC(x) ((u8) ((x) >> 8))
188	#define ASCQ(x) ((u8) (x))
189
190
191	/-------------------------------------------------------------------------/
192
193
194	struct lun {
195	struct file *filp;
196	loff_t file_length;
197	loff_t num_sectors;
198
199	unsigned int ro : 1;
200	unsigned int prevent_medium_removal : 1;
201	unsigned int registered : 1;
202	unsigned int info_valid : 1;
203
204	u32 sense_data;
205	u32 sense_data_info;
206	u32 unit_attention_data;
207
208	struct device dev;
209	};
210
211	#define backing_file_is_open(curlun) ((curlun)->filp != NULL)
212
213	static struct lun dev_to_lun(struct device dev)
214	{
215	return container_of(dev, struct lun, dev);
216	}
217
218
219	/* Big enough to hold our biggest descriptor */
220	#define EP0_BUFSIZE 256
221	#define DELAYED_STATUS (EP0_BUFSIZE + 999) // An impossibly large value
222
223	/* Number of buffers we will use. 2 is enough for double-buffering */
224	#define NUM_BUFFERS 2
225
226	enum fsg_buffer_state {
227	BUF_STATE_EMPTY = 0,
228	BUF_STATE_FULL,
229	BUF_STATE_BUSY
230	};
231
232	struct fsg_buffhd {
233	void *buf;
234	enum fsg_buffer_state state;
235	struct fsg_buffhd *next;
236
237	/* The NetChip 2280 is faster, and handles some protocol faults
238	* better, if we don't submit any short bulk-out read requests.
239	* So we will record the intended request length here. */
240	unsigned int bulk_out_intended_length;
241
242	struct usb_request *inreq;
243	int inreq_busy;
244	struct usb_request *outreq;
245	int outreq_busy;
246	};
247
248	enum fsg_state {
249	FSG_STATE_COMMAND_PHASE = -10, // This one isn't used anywhere
250	FSG_STATE_DATA_PHASE,
251	FSG_STATE_STATUS_PHASE,
252
253	FSG_STATE_IDLE = 0,
254	FSG_STATE_ABORT_BULK_OUT,
255	FSG_STATE_RESET,
256	FSG_STATE_INTERFACE_CHANGE,
257	FSG_STATE_CONFIG_CHANGE,
258	FSG_STATE_DISCONNECT,
259	FSG_STATE_EXIT,
260	FSG_STATE_TERMINATED
261	};
262
263	enum data_direction {
264	DATA_DIR_UNKNOWN = 0,
265	DATA_DIR_FROM_HOST,
266	DATA_DIR_TO_HOST,
267	DATA_DIR_NONE
268	};
269
270
271	/-------------------------------------------------------------------------/
272
273
274	static inline u32 get_unaligned_be24(u8 *buf)
275	{
276	return 0xffffff & (u32) get_unaligned_be32(buf - 1);
277	}
278
279
280	/-------------------------------------------------------------------------/
281
282
283	#define STRING_MANUFACTURER 1
284	#define STRING_PRODUCT 2
285	#define STRING_SERIAL 3
286	#define STRING_CONFIG 4
287	#define STRING_INTERFACE 5
288
289
290	static struct usb_otg_descriptor
291	otg_desc = {
292	.bLength = sizeof(otg_desc),
293	.bDescriptorType = USB_DT_OTG,
294
295	.bmAttributes = USB_OTG_SRP,
296	};
297
298	/* There is only one interface. */
299
300	static struct usb_interface_descriptor
301	intf_desc = {
302	.bLength = sizeof intf_desc,
303	.bDescriptorType = USB_DT_INTERFACE,
304
305	.bNumEndpoints = 2, // Adjusted during fsg_bind()
306	.bInterfaceClass = USB_CLASS_MASS_STORAGE,
307	.bInterfaceSubClass = USB_SC_SCSI, // Adjusted during fsg_bind()
308	.bInterfaceProtocol = USB_PR_BULK, // Adjusted during fsg_bind()
309	.iInterface = STRING_INTERFACE,
310	};
311
312	/* Three full-speed endpoint descriptors: bulk-in, bulk-out,
313	* and interrupt-in. */
314
315	static struct usb_endpoint_descriptor
316	fs_bulk_in_desc = {
317	.bLength = USB_DT_ENDPOINT_SIZE,
318	.bDescriptorType = USB_DT_ENDPOINT,
319
320	.bEndpointAddress = USB_DIR_IN,
321	.bmAttributes = USB_ENDPOINT_XFER_BULK,
322	/* wMaxPacketSize set by autoconfiguration */
323	};
324
325	static struct usb_endpoint_descriptor
326	fs_bulk_out_desc = {
327	.bLength = USB_DT_ENDPOINT_SIZE,
328	.bDescriptorType = USB_DT_ENDPOINT,
329
330	.bEndpointAddress = USB_DIR_OUT,
331	.bmAttributes = USB_ENDPOINT_XFER_BULK,
332	/* wMaxPacketSize set by autoconfiguration */
333	};
334
335	static struct usb_endpoint_descriptor
336	fs_intr_in_desc = {
337	.bLength = USB_DT_ENDPOINT_SIZE,
338	.bDescriptorType = USB_DT_ENDPOINT,
339
340	.bEndpointAddress = USB_DIR_IN,
341	.bmAttributes = USB_ENDPOINT_XFER_INT,
342	.wMaxPacketSize = cpu_to_le16(2),
343	.bInterval = 32, // frames -> 32 ms
344	};
345
346	static const struct usb_descriptor_header *fs_function[] = {
347	(struct usb_descriptor_header *) &otg_desc,
348	(struct usb_descriptor_header *) &intf_desc,
349	(struct usb_descriptor_header *) &fs_bulk_in_desc,
350	(struct usb_descriptor_header *) &fs_bulk_out_desc,
351	(struct usb_descriptor_header *) &fs_intr_in_desc,
352	NULL,
353	};
354	#define FS_FUNCTION_PRE_EP_ENTRIES 2
355
356
357	/*
358	* USB 2.0 devices need to expose both high speed and full speed
359	* descriptors, unless they only run at full speed.
360	*
361	* That means alternate endpoint descriptors (bigger packets)
362	* and a "device qualifier" ... plus more construction options
363	* for the config descriptor.
364	*/
365	static struct usb_endpoint_descriptor
366	hs_bulk_in_desc = {
367	.bLength = USB_DT_ENDPOINT_SIZE,
368	.bDescriptorType = USB_DT_ENDPOINT,
369
370	/* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */
371	.bmAttributes = USB_ENDPOINT_XFER_BULK,
372	.wMaxPacketSize = cpu_to_le16(512),
373	};
374
375	static struct usb_endpoint_descriptor
376	hs_bulk_out_desc = {
377	.bLength = USB_DT_ENDPOINT_SIZE,
378	.bDescriptorType = USB_DT_ENDPOINT,
379
380	/* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */
381	.bmAttributes = USB_ENDPOINT_XFER_BULK,
382	.wMaxPacketSize = cpu_to_le16(512),
383	.bInterval = 1, // NAK every 1 uframe
384	};
385
386	static struct usb_endpoint_descriptor
387	hs_intr_in_desc = {
388	.bLength = USB_DT_ENDPOINT_SIZE,
389	.bDescriptorType = USB_DT_ENDPOINT,
390
391	/* bEndpointAddress copied from fs_intr_in_desc during fsg_bind() */
392	.bmAttributes = USB_ENDPOINT_XFER_INT,
393	.wMaxPacketSize = cpu_to_le16(2),
394	.bInterval = 9, // 2**(9-1) = 256 uframes -> 32 ms
395	};
396
397	static const struct usb_descriptor_header *hs_function[] = {
398	(struct usb_descriptor_header *) &otg_desc,
399	(struct usb_descriptor_header *) &intf_desc,
400	(struct usb_descriptor_header *) &hs_bulk_in_desc,
401	(struct usb_descriptor_header *) &hs_bulk_out_desc,
402	(struct usb_descriptor_header *) &hs_intr_in_desc,
403	NULL,
404	};
405	#define HS_FUNCTION_PRE_EP_ENTRIES 2
406
407	/* Maxpacket and other transfer characteristics vary by speed. */
408	static struct usb_endpoint_descriptor *
409	ep_desc(struct usb_gadget g, struct usb_endpoint_descriptor fs,
410	struct usb_endpoint_descriptor *hs)
411	{
412	if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
413	return hs;
414	return fs;
415	}
416
417
418	/* The CBI specification limits the serial string to 12 uppercase hexadecimal
419	* characters. */
420	static char manufacturer[64];
421	static char serial[13];
422
423	/* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
424	static struct usb_string strings[] = {
425	{STRING_MANUFACTURER, manufacturer},
426	{STRING_PRODUCT, longname},
427	{STRING_SERIAL, serial},
428	{STRING_CONFIG, "Self-powered"},
429	{STRING_INTERFACE, "Mass Storage"},
430	{}
431	};
432
433	static struct usb_gadget_strings stringtab = {
434	.language = 0x0409, // en-us
435	.strings = strings,
436	};
437
438
439	/-------------------------------------------------------------------------/
440
441	/* If the next two routines are called while the gadget is registered,
442	* the caller must own fsg->filesem for writing. */
443
444	static int open_backing_file(struct lun curlun, const char filename)
445	{
446	int ro;
447	struct file *filp = NULL;
448	int rc = -EINVAL;
449	struct inode *inode = NULL;
450	loff_t size;
451	loff_t num_sectors;
452	loff_t min_sectors;
453
454	/* R/W if we can, R/O if we must */
455	ro = curlun->ro;
456	if (!ro) {
457	filp = filp_open(filename, O_RDWR \| O_LARGEFILE, 0);
458	if (-EROFS == PTR_ERR(filp))
459	ro = 1;
460	}
461	if (ro)
462	filp = filp_open(filename, O_RDONLY \| O_LARGEFILE, 0);
463	if (IS_ERR(filp)) {
464	LINFO(curlun, "unable to open backing file: %s\n", filename);
465	return PTR_ERR(filp);
466	}
467
468	if (!(filp->f_mode & FMODE_WRITE))
469	ro = 1;
470
471	if (filp->f_path.dentry)
472	inode = filp->f_path.dentry->d_inode;
473	if (inode && S_ISBLK(inode->i_mode)) {
474	if (bdev_read_only(inode->i_bdev))
475	ro = 1;
476	} else if (!inode \|\| !S_ISREG(inode->i_mode)) {
477	LINFO(curlun, "invalid file type: %s\n", filename);
478	goto out;
479	}
480
481	/* If we can't read the file, it's no good.
482	* If we can't write the file, use it read-only. */
483	if (!filp->f_op \|\| !(filp->f_op->read \|\| filp->f_op->aio_read)) {
484	LINFO(curlun, "file not readable: %s\n", filename);
485	goto out;
486	}
487	if (!(filp->f_op->write \|\| filp->f_op->aio_write))
488	ro = 1;
489
490	size = i_size_read(inode->i_mapping->host);
491	if (size < 0) {
492	LINFO(curlun, "unable to find file size: %s\n", filename);
493	rc = (int) size;
494	goto out;
495	}
496	num_sectors = size >> 9; // File size in 512-byte blocks
497	min_sectors = 1;
498	if (mod_data.cdrom) {
499	num_sectors &= ~3; // Reduce to a multiple of 2048
500	min_sectors = 300*4; // Smallest track is 300 frames
501	if (num_sectors >= 2566075*4) {
502	num_sectors = (2566075 - 1) * 4;
503	LINFO(curlun, "file too big: %s\n", filename);
504	LINFO(curlun, "using only first %d blocks\n",
505	(int) num_sectors);
506	}
507	}
508	if (num_sectors < min_sectors) {
509	LINFO(curlun, "file too small: %s\n", filename);
510	rc = -ETOOSMALL;
511	goto out;
512	}
513
514	get_file(filp);
515	curlun->ro = ro;
516	curlun->filp = filp;
517	curlun->file_length = size;
518	curlun->num_sectors = num_sectors;
519	LDBG(curlun, "open backing file: %s\n", filename);
520	rc = 0;
521
522	out:
523	filp_close(filp, current->files);
524	return rc;
525	}
526
527
528	static void close_backing_file(struct lun *curlun)
529	{
530	if (curlun->filp) {
531	LDBG(curlun, "close backing file\n");
532	fput(curlun->filp);
533	curlun->filp = NULL;
534	}
535	}
536
537
538	/-------------------------------------------------------------------------/
539
540	/* Sync the file data, don't bother with the metadata.
541	* This code was copied from fs/buffer.c:sys_fdatasync(). */
542	static int fsync_sub(struct lun *curlun)
543	{
544	struct file *filp = curlun->filp;
545
546	if (curlun->ro \|\| !filp)
547	return 0;
548	return vfs_fsync(filp, filp->f_path.dentry, 1);
549	}
550
551	static void store_cdrom_address(u8 *dest, int msf, u32 addr)
552	{
553	if (msf) {
554	/* Convert to Minutes-Seconds-Frames */
555	addr >>= 2; /* Convert to 2048-byte frames */
556	addr += 275; / Lead-in occupies 2 seconds */
557	dest[3] = addr % 75; /* Frames */
558	addr /= 75;
559	dest[2] = addr % 60; /* Seconds */
560	addr /= 60;
561	dest[1] = addr; /* Minutes */
562	dest[0] = 0; /* Reserved */
563	} else {
564	/* Absolute sector */
565	put_unaligned_be32(addr, dest);
566	}
567	}