2 * storage_common.c -- Common definitions for mass storage functionality
4 * Copyright (C) 2003-2008 Alan Stern
5 * Copyeight (C) 2009 Samsung Electronics
6 * Author: Michal Nazarewicz (mina86@mina86.com)
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
15 * This file requires the following identifiers used in USB strings to
16 * be defined (each of type pointer to char):
17 * - fsg_string_interface -- name of the interface
21 * When USB_GADGET_DEBUG_FILES is defined the module param num_buffers
22 * sets the number of pipeline buffers (length of the fsg_buffhd array).
23 * The valid range of num_buffers is: num >= 2 && num <= 4.
27 #include <linux/usb/storage.h>
28 #include <scsi/scsi.h>
29 #include <asm/unaligned.h>
33 * Thanks to NetChip Technologies for donating this product ID.
35 * DO NOT REUSE THESE IDs with any other driver!! Ever!!
36 * Instead: allocate your own, using normal USB-IF procedures.
38 #define FSG_VENDOR_ID 0x0525 /* NetChip */
39 #define FSG_PRODUCT_ID 0xa4a5 /* Linux-USB File-backed Storage Gadget */
42 /*-------------------------------------------------------------------------*/
53 #define VLDBG(lun, fmt, args...) do { } while (0)
54 #endif /* VERBOSE_DEBUG */
56 #define LDBG(lun, fmt, args...) dev_dbg (&(lun)->dev, fmt, ## args)
57 #define LERROR(lun, fmt, args...) dev_err (&(lun)->dev, fmt, ## args)
58 #define LWARN(lun, fmt, args...) dev_warn(&(lun)->dev, fmt, ## args)
59 #define LINFO(lun, fmt, args...) dev_info(&(lun)->dev, fmt, ## args)
64 # define dump_msg(fsg, /* const char * */ label, \
65 /* const u8 * */ buf, /* unsigned */ length) do { \
67 DBG(fsg, "%s, length %u:\n", label, length); \
68 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, \
69 16, 1, buf, length, 0); \
73 # define dump_cdb(fsg) do { } while (0)
77 # define dump_msg(fsg, /* const char * */ label, \
78 /* const u8 * */ buf, /* unsigned */ length) do { } while (0)
82 # define dump_cdb(fsg) \
83 print_hex_dump(KERN_DEBUG, "SCSI CDB: ", DUMP_PREFIX_NONE, \
84 16, 1, (fsg)->cmnd, (fsg)->cmnd_size, 0) \
88 # define dump_cdb(fsg) do { } while (0)
90 # endif /* VERBOSE_DEBUG */
92 #endif /* DUMP_MSGS */
94 /*-------------------------------------------------------------------------*/
96 /* CBI Interrupt data structure */
97 struct interrupt_data {
102 #define CBI_INTERRUPT_DATA_LEN 2
104 /* CBI Accept Device-Specific Command request */
105 #define USB_CBI_ADSC_REQUEST 0x00
108 /* Length of a SCSI Command Data Block */
109 #define MAX_COMMAND_SIZE 16
111 /* SCSI Sense Key/Additional Sense Code/ASC Qualifier values */
112 #define SS_NO_SENSE 0
113 #define SS_COMMUNICATION_FAILURE 0x040800
114 #define SS_INVALID_COMMAND 0x052000
115 #define SS_INVALID_FIELD_IN_CDB 0x052400
116 #define SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE 0x052100
117 #define SS_LOGICAL_UNIT_NOT_SUPPORTED 0x052500
118 #define SS_MEDIUM_NOT_PRESENT 0x023a00
119 #define SS_MEDIUM_REMOVAL_PREVENTED 0x055302
120 #define SS_NOT_READY_TO_READY_TRANSITION 0x062800
121 #define SS_RESET_OCCURRED 0x062900
122 #define SS_SAVING_PARAMETERS_NOT_SUPPORTED 0x053900
123 #define SS_UNRECOVERED_READ_ERROR 0x031100
124 #define SS_WRITE_ERROR 0x030c02
125 #define SS_WRITE_PROTECTED 0x072700
127 #define SK(x) ((u8) ((x) >> 16)) /* Sense Key byte, etc. */
128 #define ASC(x) ((u8) ((x) >> 8))
129 #define ASCQ(x) ((u8) (x))
132 /*-------------------------------------------------------------------------*/
140 unsigned int initially_ro:1;
142 unsigned int removable:1;
143 unsigned int cdrom:1;
144 unsigned int prevent_medium_removal:1;
145 unsigned int registered:1;
146 unsigned int info_valid:1;
147 unsigned int nofua:1;
151 u32 unit_attention_data;
153 unsigned int blkbits; /* Bits of logical block size of bound block device */
154 unsigned int blksize; /* logical block size of bound block device */
158 static inline bool fsg_lun_is_open(struct fsg_lun *curlun)
160 return curlun->filp != NULL;
163 static inline struct fsg_lun *fsg_lun_from_dev(struct device *dev)
165 return container_of(dev, struct fsg_lun, dev);
169 /* Big enough to hold our biggest descriptor */
170 #define EP0_BUFSIZE 256
171 #define DELAYED_STATUS (EP0_BUFSIZE + 999) /* An impossibly large value */
173 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
175 static unsigned int fsg_num_buffers = CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS;
176 module_param_named(num_buffers, fsg_num_buffers, uint, S_IRUGO);
177 MODULE_PARM_DESC(num_buffers, "Number of pipeline buffers");
182 * Number of buffers we will use.
183 * 2 is usually enough for good buffering pipeline
185 #define fsg_num_buffers CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS
187 #endif /* CONFIG_USB_DEBUG */
189 /* check if fsg_num_buffers is within a valid range */
190 static inline int fsg_num_buffers_validate(void)
192 if (fsg_num_buffers >= 2 && fsg_num_buffers <= 4)
194 pr_err("fsg_num_buffers %u is out of range (%d to %d)\n",
195 fsg_num_buffers, 2 ,4);
199 /* Default size of buffer length. */
200 #define FSG_BUFLEN ((u32)16384)
202 /* Maximal number of LUNs supported in mass storage function */
203 #define FSG_MAX_LUNS 8
205 enum fsg_buffer_state {
213 enum fsg_buffer_state state;
214 struct fsg_buffhd *next;
217 * The NetChip 2280 is faster, and handles some protocol faults
218 * better, if we don't submit any short bulk-out read requests.
219 * So we will record the intended request length here.
221 unsigned int bulk_out_intended_length;
223 struct usb_request *inreq;
225 struct usb_request *outreq;
230 /* This one isn't used anywhere */
231 FSG_STATE_COMMAND_PHASE = -10,
232 FSG_STATE_DATA_PHASE,
233 FSG_STATE_STATUS_PHASE,
236 FSG_STATE_ABORT_BULK_OUT,
238 FSG_STATE_INTERFACE_CHANGE,
239 FSG_STATE_CONFIG_CHANGE,
240 FSG_STATE_DISCONNECT,
245 enum data_direction {
246 DATA_DIR_UNKNOWN = 0,
253 /*-------------------------------------------------------------------------*/
256 static inline u32 get_unaligned_be24(u8 *buf)
258 return 0xffffff & (u32) get_unaligned_be32(buf - 1);
262 /*-------------------------------------------------------------------------*/
270 /* There is only one interface. */
272 static struct usb_interface_descriptor
274 .bLength = sizeof fsg_intf_desc,
275 .bDescriptorType = USB_DT_INTERFACE,
277 .bNumEndpoints = 2, /* Adjusted during fsg_bind() */
278 .bInterfaceClass = USB_CLASS_MASS_STORAGE,
279 .bInterfaceSubClass = USB_SC_SCSI, /* Adjusted during fsg_bind() */
280 .bInterfaceProtocol = USB_PR_BULK, /* Adjusted during fsg_bind() */
281 .iInterface = FSG_STRING_INTERFACE,
285 * Three full-speed endpoint descriptors: bulk-in, bulk-out, and
289 static struct usb_endpoint_descriptor
290 fsg_fs_bulk_in_desc = {
291 .bLength = USB_DT_ENDPOINT_SIZE,
292 .bDescriptorType = USB_DT_ENDPOINT,
294 .bEndpointAddress = USB_DIR_IN,
295 .bmAttributes = USB_ENDPOINT_XFER_BULK,
296 /* wMaxPacketSize set by autoconfiguration */
299 static struct usb_endpoint_descriptor
300 fsg_fs_bulk_out_desc = {
301 .bLength = USB_DT_ENDPOINT_SIZE,
302 .bDescriptorType = USB_DT_ENDPOINT,
304 .bEndpointAddress = USB_DIR_OUT,
305 .bmAttributes = USB_ENDPOINT_XFER_BULK,
306 /* wMaxPacketSize set by autoconfiguration */
309 static struct usb_descriptor_header *fsg_fs_function[] = {
310 (struct usb_descriptor_header *) &fsg_intf_desc,
311 (struct usb_descriptor_header *) &fsg_fs_bulk_in_desc,
312 (struct usb_descriptor_header *) &fsg_fs_bulk_out_desc,
318 * USB 2.0 devices need to expose both high speed and full speed
319 * descriptors, unless they only run at full speed.
321 * That means alternate endpoint descriptors (bigger packets)
322 * and a "device qualifier" ... plus more construction options
323 * for the configuration descriptor.
325 static struct usb_endpoint_descriptor
326 fsg_hs_bulk_in_desc = {
327 .bLength = USB_DT_ENDPOINT_SIZE,
328 .bDescriptorType = USB_DT_ENDPOINT,
330 /* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */
331 .bmAttributes = USB_ENDPOINT_XFER_BULK,
332 .wMaxPacketSize = cpu_to_le16(512),
335 static struct usb_endpoint_descriptor
336 fsg_hs_bulk_out_desc = {
337 .bLength = USB_DT_ENDPOINT_SIZE,
338 .bDescriptorType = USB_DT_ENDPOINT,
340 /* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */
341 .bmAttributes = USB_ENDPOINT_XFER_BULK,
342 .wMaxPacketSize = cpu_to_le16(512),
343 .bInterval = 1, /* NAK every 1 uframe */
347 static struct usb_descriptor_header *fsg_hs_function[] = {
348 (struct usb_descriptor_header *) &fsg_intf_desc,
349 (struct usb_descriptor_header *) &fsg_hs_bulk_in_desc,
350 (struct usb_descriptor_header *) &fsg_hs_bulk_out_desc,
354 static struct usb_endpoint_descriptor
355 fsg_ss_bulk_in_desc = {
356 .bLength = USB_DT_ENDPOINT_SIZE,
357 .bDescriptorType = USB_DT_ENDPOINT,
359 /* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */
360 .bmAttributes = USB_ENDPOINT_XFER_BULK,
361 .wMaxPacketSize = cpu_to_le16(1024),
364 static struct usb_ss_ep_comp_descriptor fsg_ss_bulk_in_comp_desc = {
365 .bLength = sizeof(fsg_ss_bulk_in_comp_desc),
366 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
368 /*.bMaxBurst = DYNAMIC, */
371 static struct usb_endpoint_descriptor
372 fsg_ss_bulk_out_desc = {
373 .bLength = USB_DT_ENDPOINT_SIZE,
374 .bDescriptorType = USB_DT_ENDPOINT,
376 /* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */
377 .bmAttributes = USB_ENDPOINT_XFER_BULK,
378 .wMaxPacketSize = cpu_to_le16(1024),
381 static struct usb_ss_ep_comp_descriptor fsg_ss_bulk_out_comp_desc = {
382 .bLength = sizeof(fsg_ss_bulk_in_comp_desc),
383 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
385 /*.bMaxBurst = DYNAMIC, */
388 static __maybe_unused struct usb_ext_cap_descriptor fsg_ext_cap_desc = {
389 .bLength = USB_DT_USB_EXT_CAP_SIZE,
390 .bDescriptorType = USB_DT_DEVICE_CAPABILITY,
391 .bDevCapabilityType = USB_CAP_TYPE_EXT,
393 .bmAttributes = cpu_to_le32(USB_LPM_SUPPORT),
396 static __maybe_unused struct usb_ss_cap_descriptor fsg_ss_cap_desc = {
397 .bLength = USB_DT_USB_SS_CAP_SIZE,
398 .bDescriptorType = USB_DT_DEVICE_CAPABILITY,
399 .bDevCapabilityType = USB_SS_CAP_TYPE,
401 /* .bmAttributes = LTM is not supported yet */
403 .wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION
404 | USB_FULL_SPEED_OPERATION
405 | USB_HIGH_SPEED_OPERATION
406 | USB_5GBPS_OPERATION),
407 .bFunctionalitySupport = USB_LOW_SPEED_OPERATION,
408 .bU1devExitLat = USB_DEFAULT_U1_DEV_EXIT_LAT,
409 .bU2DevExitLat = cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT),
412 static __maybe_unused struct usb_bos_descriptor fsg_bos_desc = {
413 .bLength = USB_DT_BOS_SIZE,
414 .bDescriptorType = USB_DT_BOS,
416 .wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE
417 + USB_DT_USB_EXT_CAP_SIZE
418 + USB_DT_USB_SS_CAP_SIZE),
423 static struct usb_descriptor_header *fsg_ss_function[] = {
424 (struct usb_descriptor_header *) &fsg_intf_desc,
425 (struct usb_descriptor_header *) &fsg_ss_bulk_in_desc,
426 (struct usb_descriptor_header *) &fsg_ss_bulk_in_comp_desc,
427 (struct usb_descriptor_header *) &fsg_ss_bulk_out_desc,
428 (struct usb_descriptor_header *) &fsg_ss_bulk_out_comp_desc,
432 /* Maxpacket and other transfer characteristics vary by speed. */
433 static __maybe_unused struct usb_endpoint_descriptor *
434 fsg_ep_desc(struct usb_gadget *g, struct usb_endpoint_descriptor *fs,
435 struct usb_endpoint_descriptor *hs,
436 struct usb_endpoint_descriptor *ss)
438 if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER)
440 else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
446 /* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
447 static struct usb_string fsg_strings[] = {
448 {FSG_STRING_INTERFACE, fsg_string_interface},
452 static struct usb_gadget_strings fsg_stringtab = {
453 .language = 0x0409, /* en-us */
454 .strings = fsg_strings,
458 /*-------------------------------------------------------------------------*/
461 * If the next two routines are called while the gadget is registered,
462 * the caller must own fsg->filesem for writing.
465 static void fsg_lun_close(struct fsg_lun *curlun)
468 LDBG(curlun, "close backing file\n");
475 static int fsg_lun_open(struct fsg_lun *curlun, const char *filename)
478 struct file *filp = NULL;
480 struct inode *inode = NULL;
484 unsigned int blkbits;
485 unsigned int blksize;
487 /* R/W if we can, R/O if we must */
488 ro = curlun->initially_ro;
490 filp = filp_open(filename, O_RDWR | O_LARGEFILE, 0);
491 if (PTR_ERR(filp) == -EROFS || PTR_ERR(filp) == -EACCES)
495 filp = filp_open(filename, O_RDONLY | O_LARGEFILE, 0);
497 LINFO(curlun, "unable to open backing file: %s\n", filename);
498 return PTR_ERR(filp);
501 if (!(filp->f_mode & FMODE_WRITE))
504 inode = filp->f_path.dentry->d_inode;
505 if ((!S_ISREG(inode->i_mode) && !S_ISBLK(inode->i_mode))) {
506 LINFO(curlun, "invalid file type: %s\n", filename);
511 * If we can't read the file, it's no good.
512 * If we can't write the file, use it read-only.
514 if (!(filp->f_op->read || filp->f_op->aio_read)) {
515 LINFO(curlun, "file not readable: %s\n", filename);
518 if (!(filp->f_op->write || filp->f_op->aio_write))
521 size = i_size_read(inode->i_mapping->host);
523 LINFO(curlun, "unable to find file size: %s\n", filename);
531 } else if (inode->i_bdev) {
532 blksize = bdev_logical_block_size(inode->i_bdev);
533 blkbits = blksize_bits(blksize);
539 num_sectors = size >> blkbits; /* File size in logic-block-size blocks */
542 min_sectors = 300; /* Smallest track is 300 frames */
543 if (num_sectors >= 256*60*75) {
544 num_sectors = 256*60*75 - 1;
545 LINFO(curlun, "file too big: %s\n", filename);
546 LINFO(curlun, "using only first %d blocks\n",
550 if (num_sectors < min_sectors) {
551 LINFO(curlun, "file too small: %s\n", filename);
556 if (fsg_lun_is_open(curlun))
557 fsg_lun_close(curlun);
559 curlun->blksize = blksize;
560 curlun->blkbits = blkbits;
563 curlun->file_length = size;
564 curlun->num_sectors = num_sectors;
565 LDBG(curlun, "open backing file: %s\n", filename);
574 /*-------------------------------------------------------------------------*/
577 * Sync the file data, don't bother with the metadata.
578 * This code was copied from fs/buffer.c:sys_fdatasync().
580 static int fsg_lun_fsync_sub(struct fsg_lun *curlun)
582 struct file *filp = curlun->filp;
584 if (curlun->ro || !filp)
586 return vfs_fsync(filp, 1);
589 static void store_cdrom_address(u8 *dest, int msf, u32 addr)
592 /* Convert to Minutes-Seconds-Frames */
593 addr >>= 2; /* Convert to 2048-byte frames */
594 addr += 2*75; /* Lead-in occupies 2 seconds */
595 dest[3] = addr % 75; /* Frames */
597 dest[2] = addr % 60; /* Seconds */
599 dest[1] = addr; /* Minutes */
600 dest[0] = 0; /* Reserved */
602 /* Absolute sector */
603 put_unaligned_be32(addr, dest);
608 /*-------------------------------------------------------------------------*/
611 static ssize_t fsg_show_ro(struct device *dev, struct device_attribute *attr,
614 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
616 return sprintf(buf, "%d\n", fsg_lun_is_open(curlun)
618 : curlun->initially_ro);
621 static ssize_t fsg_show_nofua(struct device *dev, struct device_attribute *attr,
624 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
626 return sprintf(buf, "%u\n", curlun->nofua);
629 static ssize_t fsg_show_file(struct device *dev, struct device_attribute *attr,
632 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
633 struct rw_semaphore *filesem = dev_get_drvdata(dev);
638 if (fsg_lun_is_open(curlun)) { /* Get the complete pathname */
639 p = d_path(&curlun->filp->f_path, buf, PAGE_SIZE - 1);
645 buf[rc] = '\n'; /* Add a newline */
648 } else { /* No file, return 0 bytes */
657 static ssize_t fsg_store_ro(struct device *dev, struct device_attribute *attr,
658 const char *buf, size_t count)
661 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
662 struct rw_semaphore *filesem = dev_get_drvdata(dev);
665 rc = kstrtouint(buf, 2, &ro);
670 * Allow the write-enable status to change only while the
671 * backing file is closed.
674 if (fsg_lun_is_open(curlun)) {
675 LDBG(curlun, "read-only status change prevented\n");
679 curlun->initially_ro = ro;
680 LDBG(curlun, "read-only status set to %d\n", curlun->ro);
687 static ssize_t fsg_store_nofua(struct device *dev,
688 struct device_attribute *attr,
689 const char *buf, size_t count)
691 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
695 ret = kstrtouint(buf, 2, &nofua);
699 /* Sync data when switching from async mode to sync */
700 if (!nofua && curlun->nofua)
701 fsg_lun_fsync_sub(curlun);
703 curlun->nofua = nofua;
708 static ssize_t fsg_store_file(struct device *dev, struct device_attribute *attr,
709 const char *buf, size_t count)
711 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
712 struct rw_semaphore *filesem = dev_get_drvdata(dev);
715 if (curlun->prevent_medium_removal && fsg_lun_is_open(curlun)) {
716 LDBG(curlun, "eject attempt prevented\n");
717 return -EBUSY; /* "Door is locked" */
720 /* Remove a trailing newline */
721 if (count > 0 && buf[count-1] == '\n')
722 ((char *) buf)[count-1] = 0; /* Ugh! */
724 /* Load new medium */
726 if (count > 0 && buf[0]) {
727 /* fsg_lun_open() will close existing file if any. */
728 rc = fsg_lun_open(curlun, buf);
730 curlun->unit_attention_data =
731 SS_NOT_READY_TO_READY_TRANSITION;
732 } else if (fsg_lun_is_open(curlun)) {
733 fsg_lun_close(curlun);
734 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
737 return (rc < 0 ? rc : count);