diff options
Diffstat (limited to 'drivers/usb/gadget/f_mass_storage.c')
-rw-r--r-- | drivers/usb/gadget/f_mass_storage.c | 99 |
1 files changed, 85 insertions, 14 deletions
diff --git a/drivers/usb/gadget/f_mass_storage.c b/drivers/usb/gadget/f_mass_storage.c index f4911c09022e..c904aa39ad84 100644 --- a/drivers/usb/gadget/f_mass_storage.c +++ b/drivers/usb/gadget/f_mass_storage.c @@ -163,6 +163,10 @@ * ro setting are not allowed when the medium is loaded or if CD-ROM * emulation is being used. * + * When a LUN receive an "eject" SCSI request (Start/Stop Unit), + * if the LUN is removable, the backing file is released to simulate + * ejection. + * * * This function is heavily based on "File-backed Storage Gadget" by * Alan Stern which in turn is heavily based on "Gadget Zero" by David @@ -302,7 +306,6 @@ static const char fsg_string_interface[] = "Mass Storage"; #define FSG_NO_INTR_EP 1 -#define FSG_BUFFHD_STATIC_BUFFER 1 #define FSG_NO_DEVICE_STRINGS 1 #define FSG_NO_OTG 1 #define FSG_NO_INTR_EP 1 @@ -1385,12 +1388,50 @@ static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh) static int do_start_stop(struct fsg_common *common) { - if (!common->curlun) { + struct fsg_lun *curlun = common->curlun; + int loej, start; + + if (!curlun) { return -EINVAL; - } else if (!common->curlun->removable) { - common->curlun->sense_data = SS_INVALID_COMMAND; + } else if (!curlun->removable) { + curlun->sense_data = SS_INVALID_COMMAND; return -EINVAL; } + + loej = common->cmnd[4] & 0x02; + start = common->cmnd[4] & 0x01; + + /* eject code from file_storage.c:do_start_stop() */ + + if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */ + (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */ + curlun->sense_data = SS_INVALID_FIELD_IN_CDB; + return -EINVAL; + } + + if (!start) { + /* Are we allowed to unload the media? */ + if (curlun->prevent_medium_removal) { + LDBG(curlun, "unload attempt prevented\n"); + curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED; + return -EINVAL; + } + if (loej) { /* Simulate an unload/eject */ + up_read(&common->filesem); + down_write(&common->filesem); + fsg_lun_close(curlun); + up_write(&common->filesem); + down_read(&common->filesem); + } + } else { + + /* Our emulation doesn't support mounting; the medium is + * available for use as soon as it is loaded. */ + if (!fsg_lun_is_open(curlun)) { + curlun->sense_data = SS_MEDIUM_NOT_PRESENT; + return -EINVAL; + } + } return 0; } @@ -2762,13 +2803,19 @@ static struct fsg_common *fsg_common_init(struct fsg_common *common, /* Data buffers cyclic list */ - /* Buffers in buffhds are static -- no need for additional - * allocation. */ bh = common->buffhds; - i = FSG_NUM_BUFFERS - 1; + i = FSG_NUM_BUFFERS; + goto buffhds_first_it; do { bh->next = bh + 1; - } while (++bh, --i); + ++bh; +buffhds_first_it: + bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL); + if (unlikely(!bh->buf)) { + rc = -ENOMEM; + goto error_release; + } + } while (--i); bh->next = common->buffhds; @@ -2871,6 +2918,7 @@ static void fsg_common_release(struct kref *ref) container_of(ref, struct fsg_common, ref); unsigned i = common->nluns; struct fsg_lun *lun = common->luns; + struct fsg_buffhd *bh; /* If the thread isn't already dead, tell it to exit now */ if (common->state != FSG_STATE_TERMINATED) { @@ -2892,6 +2940,13 @@ static void fsg_common_release(struct kref *ref) } kfree(common->luns); + + i = FSG_NUM_BUFFERS; + bh = common->buffhds; + do { + kfree(bh->buf); + } while (++bh, --i); + if (common->free_storage_on_release) kfree(common); } @@ -2906,6 +2961,8 @@ static void fsg_unbind(struct usb_configuration *c, struct usb_function *f) DBG(fsg, "unbind\n"); fsg_common_put(fsg->common); + usb_free_descriptors(fsg->function.descriptors); + usb_free_descriptors(fsg->function.hs_descriptors); kfree(fsg); } @@ -2946,7 +3003,9 @@ static int __init fsg_bind(struct usb_configuration *c, struct usb_function *f) fsg_fs_bulk_in_desc.bEndpointAddress; fsg_hs_bulk_out_desc.bEndpointAddress = fsg_fs_bulk_out_desc.bEndpointAddress; - f->hs_descriptors = fsg_hs_function; + f->hs_descriptors = usb_copy_descriptors(fsg_hs_function); + if (unlikely(!f->hs_descriptors)) + return -ENOMEM; } return 0; @@ -2978,7 +3037,11 @@ static int fsg_add(struct usb_composite_dev *cdev, fsg->function.name = FSG_DRIVER_DESC; fsg->function.strings = fsg_strings_array; - fsg->function.descriptors = fsg_fs_function; + fsg->function.descriptors = usb_copy_descriptors(fsg_fs_function); + if (unlikely(!fsg->function.descriptors)) { + rc = -ENOMEM; + goto error_free_fsg; + } fsg->function.bind = fsg_bind; fsg->function.unbind = fsg_unbind; fsg->function.setup = fsg_setup; @@ -2993,11 +3056,19 @@ static int fsg_add(struct usb_composite_dev *cdev, * call to usb_add_function() was successful. */ rc = usb_add_function(c, &fsg->function); + if (unlikely(rc)) + goto error_free_all; - if (likely(rc == 0)) - fsg_common_get(fsg->common); - else - kfree(fsg); + fsg_common_get(fsg->common); + return 0; + +error_free_all: + usb_free_descriptors(fsg->function.descriptors); + /* fsg_bind() might have copied those; or maybe not? who cares + * -- free it just in case. */ + usb_free_descriptors(fsg->function.hs_descriptors); +error_free_fsg: + kfree(fsg); return rc; } |