1 files changed, 85 insertions, 19 deletions

diff --git a/drivers/usb/gadget/file_storage.c b/drivers/usb/gadget/file_storage.c
index b49d86e3e45b..a857b7ac238c 100644
--- a/drivers/usb/gadget/file_storage.c
+++ b/drivers/usb/gadget/file_storage.c
@@ -56,7 +56,7 @@
  * following protocols: RBC (0x01), ATAPI or SFF-8020i (0x02), QIC-157 (0c03),
  * UFI (0x04), SFF-8070i (0x05), and transparent SCSI (0x06), selected by
  * the optional "protocol" module parameter.  In addition, the default
- * Vendor ID, Product ID, and release number can be overridden.
+ * Vendor ID, Product ID, release number and serial number can be overridden.
  *
  * There is support for multiple logical units (LUNs), each of which has
  * its own backing file.  The number of LUNs can be set using the optional
@@ -93,6 +93,8 @@
  *      removable               Default false, boolean for removable media
  *      luns=N                  Default N = number of filenames, number of
  *                                      LUNs to support
+ *      nofua=b[,b...]          Default false, booleans for ignore FUA flag
+ *                                      in SCSI WRITE(10,12) commands
  *      stall                   Default determined according to the type of
  *                                      USB device controller (usually true),
  *                                      boolean to permit the driver to halt
@@ -106,17 +108,18 @@
  *      vendor=0xVVVV           Default 0x0525 (NetChip), USB Vendor ID
  *      product=0xPPPP          Default 0xa4a5 (FSG), USB Product ID
  *      release=0xRRRR          Override the USB release number (bcdDevice)
+ *      serial=HHHH...          Override serial number (string of hex chars)
  *      buflen=N                Default N=16384, buffer size used (will be
  *                                      rounded down to a multiple of
  *                                      PAGE_CACHE_SIZE)
  *
  * If CONFIG_USB_FILE_STORAGE_TEST is not set, only the "file", "ro",
- * "removable", "luns", "stall", and "cdrom" options are available; default
- * values are used for everything else.
+ * "removable", "luns", "nofua", "stall", and "cdrom" options are available;
+ * default values are used for everything else.
  *
  * The pathnames of the backing files and the ro settings are available in
- * the attribute files "file" and "ro" in the lun<n> subdirectory of the
- * gadget's sysfs directory.  If the "removable" option is set, writing to
+ * the attribute files "file", "nofua", and "ro" in the lun<n> subdirectory of
+ * the gadget's sysfs directory.  If the "removable" option is set, writing to
  * these files will simulate ejecting/loading the medium (writing an empty
  * line means eject) and adjusting a write-enable tab.  Changes to the ro
  * setting are not allowed when the medium is loaded or if CD-ROM emulation
@@ -270,6 +273,8 @@
 
 #define DRIVER_DESC             "File-backed Storage Gadget"
 #define DRIVER_NAME             "g_file_storage"
+/* DRIVER_VERSION must be at least 6 characters long, as it is used
+ * to generate a fallback serial number. */
 #define DRIVER_VERSION          "20 November 2008"
 
 static       char fsg_string_manufacturer[64];
@@ -301,8 +306,10 @@ MODULE_LICENSE("Dual BSD/GPL");
 static struct {
         char            *file[FSG_MAX_LUNS];
         int             ro[FSG_MAX_LUNS];
+        int             nofua[FSG_MAX_LUNS];
         unsigned int    num_filenames;
         unsigned int    num_ros;
+        unsigned int    num_nofuas;
         unsigned int    nluns;
 
         int             removable;
@@ -314,6 +321,7 @@ static struct {
         unsigned short  vendor;
         unsigned short  product;
         unsigned short  release;
+        char            *serial;
         unsigned int    buflen;
 
         int             transport_type;
@@ -341,6 +349,10 @@ MODULE_PARM_DESC(file, "names of backing files or devices");
 module_param_array_named(ro, mod_data.ro, bool, &mod_data.num_ros, S_IRUGO);
 MODULE_PARM_DESC(ro, "true to force read-only");
 
+module_param_array_named(nofua, mod_data.nofua, bool, &mod_data.num_nofuas,
+                S_IRUGO);
+MODULE_PARM_DESC(nofua, "true to ignore SCSI WRITE(10,12) FUA bit");
+
 module_param_named(luns, mod_data.nluns, uint, S_IRUGO);
 MODULE_PARM_DESC(luns, "number of LUNs");
 
@@ -353,6 +365,8 @@ MODULE_PARM_DESC(stall, "false to prevent bulk stalls");
 module_param_named(cdrom, mod_data.cdrom, bool, S_IRUGO);
 MODULE_PARM_DESC(cdrom, "true to emulate cdrom instead of disk");
 
+module_param_named(serial, mod_data.serial, charp, S_IRUGO);
+MODULE_PARM_DESC(serial, "USB serial number");
 
 /* In the non-TEST version, only the module parameters listed above
  * are available. */
@@ -1272,7 +1286,8 @@ static int do_write(struct fsg_dev *fsg)
                         curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
                         return -EINVAL;
                 }
-                if (fsg->cmnd[1] & 0x08) {      // FUA
+                /* FUA */
+                if (!curlun->nofua && (fsg->cmnd[1] & 0x08)) {
                         spin_lock(&curlun->filp->f_lock);
                         curlun->filp->f_flags |= O_DSYNC;
                         spin_unlock(&curlun->filp->f_lock);
@@ -3126,6 +3141,7 @@ static int fsg_main_thread(void *fsg_)
 
 /* The write permissions and store_xxx pointers are set in fsg_bind() */
 static DEVICE_ATTR(ro, 0444, fsg_show_ro, NULL);
+static DEVICE_ATTR(nofua, 0644, fsg_show_nofua, NULL);
 static DEVICE_ATTR(file, 0444, fsg_show_file, NULL);
 
 
@@ -3197,6 +3213,7 @@ static int __init check_parameters(struct fsg_dev *fsg)
 {
         int     prot;
         int     gcnum;
+        int     i;
 
         /* Store the default values */
         mod_data.transport_type = USB_PR_BULK;
@@ -3272,13 +3289,65 @@ static int __init check_parameters(struct fsg_dev *fsg)
                 ERROR(fsg, "invalid buflen\n");
                 return -ETOOSMALL;
         }
+
 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
 
+        /* Serial string handling.
+         * On a real device, the serial string would be loaded
+         * from permanent storage. */
+        if (mod_data.serial) {
+                const char *ch;
+                unsigned len = 0;
+
+                /* Sanity check :
+                 * The CB[I] specification limits the serial string to
+                 * 12 uppercase hexadecimal characters.
+                 * BBB need at least 12 uppercase hexadecimal characters,
+                 * with a maximum of 126. */
+                for (ch = mod_data.serial; *ch; ++ch) {
+                        ++len;
+                        if ((*ch < '0' || *ch > '9') &&
+                            (*ch < 'A' || *ch > 'F')) { /* not uppercase hex */
+                                WARNING(fsg,
+                                        "Invalid serial string character: %c; "
+                                        "Failing back to default\n",
+                                        *ch);
+                                goto fill_serial;
+                        }
+                }
+                if (len > 126 ||
+                    (mod_data.transport_type == USB_PR_BULK && len < 12) ||
+                    (mod_data.transport_type != USB_PR_BULK && len > 12)) {
+                        WARNING(fsg,
+                                "Invalid serial string length; "
+                                "Failing back to default\n");
+                        goto fill_serial;
+                }
+                fsg_strings[FSG_STRING_SERIAL - 1].s = mod_data.serial;
+        } else {
+                WARNING(fsg,
+                        "Userspace failed to provide serial number; "
+                        "Failing back to default\n");
+fill_serial:
+                /* Serial number not specified or invalid, make our own.
+                 * We just encode it from the driver version string,
+                 * 12 characters to comply with both CB[I] and BBB spec.
+                 * Warning : Two devices running the same kernel will have
+                 * the same fallback serial number. */
+                for (i = 0; i < 12; i += 2) {
+                        unsigned char   c = DRIVER_VERSION[i / 2];
+
+                        if (!c)
+                                break;
+                        sprintf(&fsg_string_serial[i], "%02X", c);
+                }
+        }
+
         return 0;
 }
 
 
-static int __init fsg_bind(struct usb_gadget *gadget)
+static int __ref fsg_bind(struct usb_gadget *gadget)
 {
         struct fsg_dev          *fsg = the_fsg;
         int                     rc;
@@ -3305,6 +3374,10 @@ static int __init fsg_bind(struct usb_gadget *gadget)
                 }
         }
 
+        /* Only for removable media? */
+        dev_attr_nofua.attr.mode = 0644;
+        dev_attr_nofua.store = fsg_store_nofua;
+
         /* Find out how many LUNs there should be */
         i = mod_data.nluns;
         if (i == 0)
@@ -3330,6 +3403,7 @@ static int __init fsg_bind(struct usb_gadget *gadget)
                 curlun->ro = mod_data.cdrom || mod_data.ro[i];
                 curlun->initially_ro = curlun->ro;
                 curlun->removable = mod_data.removable;
+                curlun->nofua = mod_data.nofua[i];
                 curlun->dev.release = lun_release;
                 curlun->dev.parent = &gadget->dev;
                 curlun->dev.driver = &fsg_driver.driver;
@@ -3344,6 +3418,8 @@ static int __init fsg_bind(struct usb_gadget *gadget)
                 if ((rc = device_create_file(&curlun->dev,
                                         &dev_attr_ro)) != 0 ||
                                 (rc = device_create_file(&curlun->dev,
+                                        &dev_attr_nofua)) != 0 ||
+                                (rc = device_create_file(&curlun->dev,
                                         &dev_attr_file)) != 0) {
                         device_unregister(&curlun->dev);
                         goto out;
@@ -3447,16 +3523,6 @@ static int __init fsg_bind(struct usb_gadget *gadget)
                         init_utsname()->sysname, init_utsname()->release,
                         gadget->name);
 
-        /* On a real device, serial[] would be loaded from permanent
-         * storage.  We just encode it from the driver version string. */
-        for (i = 0; i < sizeof fsg_string_serial - 2; i += 2) {
-                unsigned char           c = DRIVER_VERSION[i / 2];
-
-                if (!c)
-                        break;
-                sprintf(&fsg_string_serial[i], "%02X", c);
-        }
-
         fsg->thread_task = kthread_create(fsg_main_thread, fsg,
                         "file-storage-gadget");
         if (IS_ERR(fsg->thread_task)) {
@@ -3478,8 +3544,8 @@ static int __init fsg_bind(struct usb_gadget *gadget)
                                 if (IS_ERR(p))
                                         p = NULL;
                         }
-                        LINFO(curlun, "ro=%d, file: %s\n",
-                                        curlun->ro, (p ? p : "(error)"));
+                        LINFO(curlun, "ro=%d, nofua=%d, file: %s\n",
+                              curlun->ro, curlun->nofua, (p ? p : "(error)"));
                 }
         }
         kfree(pathbuf);