677 lines
17 KiB
C
677 lines
17 KiB
C
/*
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* storage_common.c -- Common definitions for mass storage functionality
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*
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* Copyright (C) 2003-2008 Alan Stern
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* Copyeight (C) 2009 Samsung Electronics
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* Author: Michal Nazarewicz (mina86@mina86.com)
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*/
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/*
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* This file requires the following identifiers used in USB strings to
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* be defined (each of type pointer to char):
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* - fsg_string_interface -- name of the interface
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*/
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/*
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* When USB_GADGET_DEBUG_FILES is defined the module param num_buffers
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* sets the number of pipeline buffers (length of the fsg_buffhd array).
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* The valid range of num_buffers is: num >= 2 && num <= 4.
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*/
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#include <linux/usb/storage.h>
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#include <scsi/scsi.h>
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#include <asm/unaligned.h>
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/*
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* Thanks to NetChip Technologies for donating this product ID.
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*
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* DO NOT REUSE THESE IDs with any other driver!! Ever!!
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* Instead: allocate your own, using normal USB-IF procedures.
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*/
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#define FSG_VENDOR_ID 0x0525 /* NetChip */
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#define FSG_PRODUCT_ID 0xa4a5 /* Linux-USB File-backed Storage Gadget */
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/*-------------------------------------------------------------------------*/
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#ifndef DEBUG
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#undef VERBOSE_DEBUG
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#undef DUMP_MSGS
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#endif /* !DEBUG */
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#ifdef VERBOSE_DEBUG
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#define VLDBG LDBG
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#else
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#define VLDBG(lun, fmt, args...) do { } while (0)
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#endif /* VERBOSE_DEBUG */
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#define LDBG(lun, fmt, args...) dev_dbg (&(lun)->dev, fmt, ## args)
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#define LERROR(lun, fmt, args...) dev_err (&(lun)->dev, fmt, ## args)
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#define LWARN(lun, fmt, args...) dev_warn(&(lun)->dev, fmt, ## args)
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#define LINFO(lun, fmt, args...) dev_info(&(lun)->dev, fmt, ## args)
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#ifdef DUMP_MSGS
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# define dump_msg(fsg, /* const char * */ label, \
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/* const u8 * */ buf, /* unsigned */ length) do { \
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if (length < 512) { \
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DBG(fsg, "%s, length %u:\n", label, length); \
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print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, \
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16, 1, buf, length, 0); \
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} \
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} while (0)
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# define dump_cdb(fsg) do { } while (0)
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#else
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# define dump_msg(fsg, /* const char * */ label, \
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/* const u8 * */ buf, /* unsigned */ length) do { } while (0)
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# ifdef VERBOSE_DEBUG
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# define dump_cdb(fsg) \
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print_hex_dump(KERN_DEBUG, "SCSI CDB: ", DUMP_PREFIX_NONE, \
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16, 1, (fsg)->cmnd, (fsg)->cmnd_size, 0) \
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# else
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# define dump_cdb(fsg) do { } while (0)
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# endif /* VERBOSE_DEBUG */
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#endif /* DUMP_MSGS */
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/*-------------------------------------------------------------------------*/
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/* Length of a SCSI Command Data Block */
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#define MAX_COMMAND_SIZE 16
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/* SCSI Sense Key/Additional Sense Code/ASC Qualifier values */
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#define SS_NO_SENSE 0
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#define SS_COMMUNICATION_FAILURE 0x040800
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#define SS_INVALID_COMMAND 0x052000
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#define SS_INVALID_FIELD_IN_CDB 0x052400
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#define SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE 0x052100
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#define SS_LOGICAL_UNIT_NOT_SUPPORTED 0x052500
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#define SS_MEDIUM_NOT_PRESENT 0x023a00
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#define SS_MEDIUM_REMOVAL_PREVENTED 0x055302
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#define SS_NOT_READY_TO_READY_TRANSITION 0x062800
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#define SS_RESET_OCCURRED 0x062900
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#define SS_SAVING_PARAMETERS_NOT_SUPPORTED 0x053900
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#define SS_UNRECOVERED_READ_ERROR 0x031100
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#define SS_WRITE_ERROR 0x030c02
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#define SS_WRITE_PROTECTED 0x072700
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#define SK(x) ((u8) ((x) >> 16)) /* Sense Key byte, etc. */
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#define ASC(x) ((u8) ((x) >> 8))
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#define ASCQ(x) ((u8) (x))
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/*-------------------------------------------------------------------------*/
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struct fsg_lun {
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struct file *filp;
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loff_t file_length;
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loff_t num_sectors;
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unsigned int initially_ro:1;
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unsigned int ro:1;
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unsigned int removable:1;
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unsigned int cdrom:1;
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unsigned int prevent_medium_removal:1;
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unsigned int registered:1;
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unsigned int info_valid:1;
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unsigned int nofua:1;
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u32 sense_data;
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u32 sense_data_info;
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u32 unit_attention_data;
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unsigned int blkbits; /* Bits of logical block size of bound block device */
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unsigned int blksize; /* logical block size of bound block device */
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struct device dev;
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};
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static inline bool fsg_lun_is_open(struct fsg_lun *curlun)
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{
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return curlun->filp != NULL;
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}
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static inline struct fsg_lun *fsg_lun_from_dev(struct device *dev)
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{
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return container_of(dev, struct fsg_lun, dev);
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}
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/* Big enough to hold our biggest descriptor */
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#define EP0_BUFSIZE 256
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#define DELAYED_STATUS (EP0_BUFSIZE + 999) /* An impossibly large value */
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#ifdef CONFIG_USB_GADGET_DEBUG_FILES
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static unsigned int fsg_num_buffers = CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS;
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module_param_named(num_buffers, fsg_num_buffers, uint, S_IRUGO);
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MODULE_PARM_DESC(num_buffers, "Number of pipeline buffers");
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#else
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/*
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* Number of buffers we will use.
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* 2 is usually enough for good buffering pipeline
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*/
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#define fsg_num_buffers CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS
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#endif /* CONFIG_USB_GADGET_DEBUG_FILES */
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/* check if fsg_num_buffers is within a valid range */
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static inline int fsg_num_buffers_validate(void)
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{
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if (fsg_num_buffers >= 2 && fsg_num_buffers <= 4)
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return 0;
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pr_err("fsg_num_buffers %u is out of range (%d to %d)\n",
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fsg_num_buffers, 2 ,4);
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return -EINVAL;
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}
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/* Default size of buffer length. */
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#define FSG_BUFLEN ((u32)16384)
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/* Maximal number of LUNs supported in mass storage function */
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#define FSG_MAX_LUNS 8
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enum fsg_buffer_state {
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BUF_STATE_EMPTY = 0,
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BUF_STATE_FULL,
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BUF_STATE_BUSY
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};
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struct fsg_buffhd {
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void *buf;
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enum fsg_buffer_state state;
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struct fsg_buffhd *next;
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/*
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* The NetChip 2280 is faster, and handles some protocol faults
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* better, if we don't submit any short bulk-out read requests.
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* So we will record the intended request length here.
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*/
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unsigned int bulk_out_intended_length;
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struct usb_request *inreq;
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int inreq_busy;
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struct usb_request *outreq;
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int outreq_busy;
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};
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enum fsg_state {
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/* This one isn't used anywhere */
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FSG_STATE_COMMAND_PHASE = -10,
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FSG_STATE_DATA_PHASE,
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FSG_STATE_STATUS_PHASE,
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FSG_STATE_IDLE = 0,
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FSG_STATE_ABORT_BULK_OUT,
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FSG_STATE_RESET,
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FSG_STATE_INTERFACE_CHANGE,
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FSG_STATE_CONFIG_CHANGE,
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FSG_STATE_DISCONNECT,
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FSG_STATE_EXIT,
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FSG_STATE_TERMINATED
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};
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enum data_direction {
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DATA_DIR_UNKNOWN = 0,
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DATA_DIR_FROM_HOST,
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DATA_DIR_TO_HOST,
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DATA_DIR_NONE
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};
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/*-------------------------------------------------------------------------*/
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static inline u32 get_unaligned_be24(u8 *buf)
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{
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return 0xffffff & (u32) get_unaligned_be32(buf - 1);
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}
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/*-------------------------------------------------------------------------*/
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enum {
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FSG_STRING_INTERFACE
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};
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/* There is only one interface. */
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static struct usb_interface_descriptor
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fsg_intf_desc = {
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.bLength = sizeof fsg_intf_desc,
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.bDescriptorType = USB_DT_INTERFACE,
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.bNumEndpoints = 2, /* Adjusted during fsg_bind() */
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.bInterfaceClass = USB_CLASS_MASS_STORAGE,
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.bInterfaceSubClass = USB_SC_SCSI, /* Adjusted during fsg_bind() */
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.bInterfaceProtocol = USB_PR_BULK, /* Adjusted during fsg_bind() */
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.iInterface = FSG_STRING_INTERFACE,
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};
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/*
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* Three full-speed endpoint descriptors: bulk-in, bulk-out, and
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* interrupt-in.
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*/
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static struct usb_endpoint_descriptor
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fsg_fs_bulk_in_desc = {
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.bLength = USB_DT_ENDPOINT_SIZE,
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.bDescriptorType = USB_DT_ENDPOINT,
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.bEndpointAddress = USB_DIR_IN,
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.bmAttributes = USB_ENDPOINT_XFER_BULK,
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/* wMaxPacketSize set by autoconfiguration */
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};
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static struct usb_endpoint_descriptor
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fsg_fs_bulk_out_desc = {
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.bLength = USB_DT_ENDPOINT_SIZE,
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.bDescriptorType = USB_DT_ENDPOINT,
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.bEndpointAddress = USB_DIR_OUT,
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.bmAttributes = USB_ENDPOINT_XFER_BULK,
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/* wMaxPacketSize set by autoconfiguration */
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};
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static struct usb_descriptor_header *fsg_fs_function[] = {
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(struct usb_descriptor_header *) &fsg_intf_desc,
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(struct usb_descriptor_header *) &fsg_fs_bulk_in_desc,
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(struct usb_descriptor_header *) &fsg_fs_bulk_out_desc,
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NULL,
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};
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/*
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* USB 2.0 devices need to expose both high speed and full speed
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* descriptors, unless they only run at full speed.
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*
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* That means alternate endpoint descriptors (bigger packets)
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* and a "device qualifier" ... plus more construction options
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* for the configuration descriptor.
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*/
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static struct usb_endpoint_descriptor
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fsg_hs_bulk_in_desc = {
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.bLength = USB_DT_ENDPOINT_SIZE,
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.bDescriptorType = USB_DT_ENDPOINT,
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/* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */
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.bmAttributes = USB_ENDPOINT_XFER_BULK,
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.wMaxPacketSize = cpu_to_le16(512),
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};
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static struct usb_endpoint_descriptor
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fsg_hs_bulk_out_desc = {
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.bLength = USB_DT_ENDPOINT_SIZE,
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.bDescriptorType = USB_DT_ENDPOINT,
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/* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */
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.bmAttributes = USB_ENDPOINT_XFER_BULK,
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.wMaxPacketSize = cpu_to_le16(512),
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.bInterval = 1, /* NAK every 1 uframe */
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};
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static struct usb_descriptor_header *fsg_hs_function[] = {
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(struct usb_descriptor_header *) &fsg_intf_desc,
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(struct usb_descriptor_header *) &fsg_hs_bulk_in_desc,
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(struct usb_descriptor_header *) &fsg_hs_bulk_out_desc,
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NULL,
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};
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static struct usb_endpoint_descriptor
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fsg_ss_bulk_in_desc = {
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.bLength = USB_DT_ENDPOINT_SIZE,
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.bDescriptorType = USB_DT_ENDPOINT,
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/* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */
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.bmAttributes = USB_ENDPOINT_XFER_BULK,
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.wMaxPacketSize = cpu_to_le16(1024),
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};
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static struct usb_ss_ep_comp_descriptor fsg_ss_bulk_in_comp_desc = {
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.bLength = sizeof(fsg_ss_bulk_in_comp_desc),
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.bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
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/*.bMaxBurst = DYNAMIC, */
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};
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static struct usb_endpoint_descriptor
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fsg_ss_bulk_out_desc = {
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.bLength = USB_DT_ENDPOINT_SIZE,
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.bDescriptorType = USB_DT_ENDPOINT,
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/* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */
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.bmAttributes = USB_ENDPOINT_XFER_BULK,
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.wMaxPacketSize = cpu_to_le16(1024),
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};
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static struct usb_ss_ep_comp_descriptor fsg_ss_bulk_out_comp_desc = {
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.bLength = sizeof(fsg_ss_bulk_in_comp_desc),
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.bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
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/*.bMaxBurst = DYNAMIC, */
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};
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static struct usb_descriptor_header *fsg_ss_function[] = {
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(struct usb_descriptor_header *) &fsg_intf_desc,
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(struct usb_descriptor_header *) &fsg_ss_bulk_in_desc,
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(struct usb_descriptor_header *) &fsg_ss_bulk_in_comp_desc,
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(struct usb_descriptor_header *) &fsg_ss_bulk_out_desc,
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(struct usb_descriptor_header *) &fsg_ss_bulk_out_comp_desc,
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NULL,
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};
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/* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
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static struct usb_string fsg_strings[] = {
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{FSG_STRING_INTERFACE, fsg_string_interface},
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{}
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};
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static struct usb_gadget_strings fsg_stringtab = {
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.language = 0x0409, /* en-us */
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.strings = fsg_strings,
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};
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/*-------------------------------------------------------------------------*/
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/*
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* If the next two routines are called while the gadget is registered,
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* the caller must own fsg->filesem for writing.
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*/
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static void fsg_lun_close(struct fsg_lun *curlun)
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{
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if (curlun->filp) {
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LDBG(curlun, "close backing file\n");
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fput(curlun->filp);
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curlun->filp = NULL;
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}
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}
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static int fsg_lun_open(struct fsg_lun *curlun, const char *filename)
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{
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int ro;
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struct file *filp = NULL;
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int rc = -EINVAL;
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struct inode *inode = NULL;
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loff_t size;
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loff_t num_sectors;
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loff_t min_sectors;
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unsigned int blkbits;
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unsigned int blksize;
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/* R/W if we can, R/O if we must */
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ro = curlun->initially_ro;
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if (!ro) {
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filp = filp_open(filename, O_RDWR | O_LARGEFILE, 0);
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if (PTR_ERR(filp) == -EROFS || PTR_ERR(filp) == -EACCES)
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ro = 1;
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}
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if (ro)
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filp = filp_open(filename, O_RDONLY | O_LARGEFILE, 0);
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if (IS_ERR(filp)) {
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LINFO(curlun, "unable to open backing file: %s\n", filename);
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return PTR_ERR(filp);
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}
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if (!(filp->f_mode & FMODE_WRITE))
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ro = 1;
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inode = file_inode(filp);
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if ((!S_ISREG(inode->i_mode) && !S_ISBLK(inode->i_mode))) {
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LINFO(curlun, "invalid file type: %s\n", filename);
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goto out;
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}
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/*
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* If we can't read the file, it's no good.
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* If we can't write the file, use it read-only.
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*/
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if (!(filp->f_op->read || filp->f_op->aio_read)) {
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LINFO(curlun, "file not readable: %s\n", filename);
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goto out;
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}
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if (!(filp->f_op->write || filp->f_op->aio_write))
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ro = 1;
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size = i_size_read(inode->i_mapping->host);
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if (size < 0) {
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LINFO(curlun, "unable to find file size: %s\n", filename);
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rc = (int) size;
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goto out;
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}
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if (curlun->cdrom) {
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blksize = 2048;
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blkbits = 11;
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} else if (inode->i_bdev) {
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blksize = bdev_logical_block_size(inode->i_bdev);
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blkbits = blksize_bits(blksize);
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} else {
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blksize = 512;
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blkbits = 9;
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}
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num_sectors = size >> blkbits; /* File size in logic-block-size blocks */
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min_sectors = 1;
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if (curlun->cdrom) {
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min_sectors = 300; /* Smallest track is 300 frames */
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if (num_sectors >= 256*60*75) {
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num_sectors = 256*60*75 - 1;
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LINFO(curlun, "file too big: %s\n", filename);
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LINFO(curlun, "using only first %d blocks\n",
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(int) num_sectors);
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}
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}
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if (num_sectors < min_sectors) {
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LINFO(curlun, "file too small: %s\n", filename);
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rc = -ETOOSMALL;
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goto out;
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}
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if (fsg_lun_is_open(curlun))
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fsg_lun_close(curlun);
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curlun->blksize = blksize;
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curlun->blkbits = blkbits;
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curlun->ro = ro;
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curlun->filp = filp;
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curlun->file_length = size;
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curlun->num_sectors = num_sectors;
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LDBG(curlun, "open backing file: %s\n", filename);
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return 0;
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out:
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fput(filp);
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return rc;
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}
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/*-------------------------------------------------------------------------*/
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|
|
/*
|
|
* Sync the file data, don't bother with the metadata.
|
|
* This code was copied from fs/buffer.c:sys_fdatasync().
|
|
*/
|
|
static int fsg_lun_fsync_sub(struct fsg_lun *curlun)
|
|
{
|
|
struct file *filp = curlun->filp;
|
|
|
|
if (curlun->ro || !filp)
|
|
return 0;
|
|
return vfs_fsync(filp, 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);
|
|
}
|
|
}
|
|
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
|
|
static ssize_t ro_show(struct device *dev, struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
struct fsg_lun *curlun = fsg_lun_from_dev(dev);
|
|
|
|
return sprintf(buf, "%d\n", fsg_lun_is_open(curlun)
|
|
? curlun->ro
|
|
: curlun->initially_ro);
|
|
}
|
|
|
|
static ssize_t nofua_show(struct device *dev, struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
struct fsg_lun *curlun = fsg_lun_from_dev(dev);
|
|
|
|
return sprintf(buf, "%u\n", curlun->nofua);
|
|
}
|
|
|
|
static ssize_t file_show(struct device *dev, struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
struct fsg_lun *curlun = fsg_lun_from_dev(dev);
|
|
struct rw_semaphore *filesem = dev_get_drvdata(dev);
|
|
char *p;
|
|
ssize_t rc;
|
|
|
|
down_read(filesem);
|
|
if (fsg_lun_is_open(curlun)) { /* Get the complete pathname */
|
|
p = d_path(&curlun->filp->f_path, buf, PAGE_SIZE - 1);
|
|
if (IS_ERR(p))
|
|
rc = PTR_ERR(p);
|
|
else {
|
|
rc = strlen(p);
|
|
memmove(buf, p, rc);
|
|
buf[rc] = '\n'; /* Add a newline */
|
|
buf[++rc] = 0;
|
|
}
|
|
} else { /* No file, return 0 bytes */
|
|
*buf = 0;
|
|
rc = 0;
|
|
}
|
|
up_read(filesem);
|
|
return rc;
|
|
}
|
|
|
|
|
|
static ssize_t ro_store(struct device *dev, struct device_attribute *attr,
|
|
const char *buf, size_t count)
|
|
{
|
|
ssize_t rc;
|
|
struct fsg_lun *curlun = fsg_lun_from_dev(dev);
|
|
struct rw_semaphore *filesem = dev_get_drvdata(dev);
|
|
unsigned ro;
|
|
|
|
rc = kstrtouint(buf, 2, &ro);
|
|
if (rc)
|
|
return rc;
|
|
|
|
/*
|
|
* Allow the write-enable status to change only while the
|
|
* backing file is closed.
|
|
*/
|
|
down_read(filesem);
|
|
if (fsg_lun_is_open(curlun)) {
|
|
LDBG(curlun, "read-only status change prevented\n");
|
|
rc = -EBUSY;
|
|
} else {
|
|
curlun->ro = ro;
|
|
curlun->initially_ro = ro;
|
|
LDBG(curlun, "read-only status set to %d\n", curlun->ro);
|
|
rc = count;
|
|
}
|
|
up_read(filesem);
|
|
return rc;
|
|
}
|
|
|
|
static ssize_t nofua_store(struct device *dev, struct device_attribute *attr,
|
|
const char *buf, size_t count)
|
|
{
|
|
struct fsg_lun *curlun = fsg_lun_from_dev(dev);
|
|
unsigned nofua;
|
|
int ret;
|
|
|
|
ret = kstrtouint(buf, 2, &nofua);
|
|
if (ret)
|
|
return ret;
|
|
|
|
/* Sync data when switching from async mode to sync */
|
|
if (!nofua && curlun->nofua)
|
|
fsg_lun_fsync_sub(curlun);
|
|
|
|
curlun->nofua = nofua;
|
|
|
|
return count;
|
|
}
|
|
|
|
static ssize_t file_store(struct device *dev, struct device_attribute *attr,
|
|
const char *buf, size_t count)
|
|
{
|
|
struct fsg_lun *curlun = fsg_lun_from_dev(dev);
|
|
struct rw_semaphore *filesem = dev_get_drvdata(dev);
|
|
int rc = 0;
|
|
|
|
if (curlun->prevent_medium_removal && fsg_lun_is_open(curlun)) {
|
|
LDBG(curlun, "eject attempt prevented\n");
|
|
return -EBUSY; /* "Door is locked" */
|
|
}
|
|
|
|
/* Remove a trailing newline */
|
|
if (count > 0 && buf[count-1] == '\n')
|
|
((char *) buf)[count-1] = 0; /* Ugh! */
|
|
|
|
/* Load new medium */
|
|
down_write(filesem);
|
|
if (count > 0 && buf[0]) {
|
|
/* fsg_lun_open() will close existing file if any. */
|
|
rc = fsg_lun_open(curlun, buf);
|
|
if (rc == 0)
|
|
curlun->unit_attention_data =
|
|
SS_NOT_READY_TO_READY_TRANSITION;
|
|
} else if (fsg_lun_is_open(curlun)) {
|
|
fsg_lun_close(curlun);
|
|
curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
|
|
}
|
|
up_write(filesem);
|
|
return (rc < 0 ? rc : count);
|
|
}
|