kernel-fxtec-pro1x/drivers/usb/gadget/storage_common.c

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/*
* storage_common.c -- Common definitions for mass storage functionality
*
* Copyright (C) 2003-2008 Alan Stern
* Copyeight (C) 2009 Samsung Electronics
* Author: Michal Nazarewicz (mina86@mina86.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
/*
* This file requires the following identifiers used in USB strings to
* be defined (each of type pointer to char):
* - fsg_string_interface -- name of the interface
*/
usb: gadget: storage: make FSG_NUM_BUFFERS variable size FSG_NUM_BUFFERS is set to 2 as default. Usually 2 buffers are enough to establish a good buffering pipeline. The number may be increased in order to compensate a for bursty VFS behaviour. Here follows a description of system that may require more than 2 buffers. * CPU ondemand governor active * latency cost for wake up and/or frequency change * DMA for IO Use case description. * Data transfer from MMC via VFS to USB. * DMA shuffles data from MMC and to USB. * The CPU wakes up every now and then to pass data in and out from VFS, which cause the bursty VFS behaviour. Test set up * Running dd on the host reading from the mass storage device * cmdline: dd if=/dev/sdb of=/dev/null bs=4k count=$((256*100)) * Caches are dropped on the host and on the device before each run Measurements on a Snowball board with ondemand_governor active. FSG_NUM_BUFFERS 2 104857600 bytes (105 MB) copied, 5.62173 s, 18.7 MB/s 104857600 bytes (105 MB) copied, 5.61811 s, 18.7 MB/s 104857600 bytes (105 MB) copied, 5.57817 s, 18.8 MB/s FSG_NUM_BUFFERS 4 104857600 bytes (105 MB) copied, 5.26839 s, 19.9 MB/s 104857600 bytes (105 MB) copied, 5.2691 s, 19.9 MB/s 104857600 bytes (105 MB) copied, 5.2711 s, 19.9 MB/s There may not be one optimal number for all boards. This is why the number is added to Kconfig. If selecting USB_GADGET_DEBUG_FILES this value may be set by a module parameter as well. Signed-off-by: Per Forlin <per.forlin@linaro.org> Acked-by: Michal Nazarewicz <mina86@mina86.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Felipe Balbi <balbi@ti.com>
2011-08-19 13:21:27 -06:00
/*
* When USB_GADGET_DEBUG_FILES is defined the module param num_buffers
* sets the number of pipeline buffers (length of the fsg_buffhd array).
* The valid range of num_buffers is: num >= 2 && num <= 4.
*/
#include <linux/module.h>
#include <linux/blkdev.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/usb/composite.h>
#include "storage_common.h"
/* There is only one interface. */
struct usb_interface_descriptor fsg_intf_desc = {
.bLength = sizeof fsg_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 = FSG_STRING_INTERFACE,
};
EXPORT_SYMBOL(fsg_intf_desc);
/*
* Three full-speed endpoint descriptors: bulk-in, bulk-out, and
* interrupt-in.
*/
struct usb_endpoint_descriptor fsg_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 */
};
EXPORT_SYMBOL(fsg_fs_bulk_in_desc);
struct usb_endpoint_descriptor fsg_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 */
};
EXPORT_SYMBOL(fsg_fs_bulk_out_desc);
struct usb_descriptor_header *fsg_fs_function[] = {
(struct usb_descriptor_header *) &fsg_intf_desc,
(struct usb_descriptor_header *) &fsg_fs_bulk_in_desc,
(struct usb_descriptor_header *) &fsg_fs_bulk_out_desc,
NULL,
};
EXPORT_SYMBOL(fsg_fs_function);
/*
* 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 configuration descriptor.
*/
struct usb_endpoint_descriptor fsg_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),
};
EXPORT_SYMBOL(fsg_hs_bulk_in_desc);
struct usb_endpoint_descriptor fsg_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 */
};
EXPORT_SYMBOL(fsg_hs_bulk_out_desc);
struct usb_descriptor_header *fsg_hs_function[] = {
(struct usb_descriptor_header *) &fsg_intf_desc,
(struct usb_descriptor_header *) &fsg_hs_bulk_in_desc,
(struct usb_descriptor_header *) &fsg_hs_bulk_out_desc,
NULL,
};
EXPORT_SYMBOL(fsg_hs_function);
struct usb_endpoint_descriptor fsg_ss_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(1024),
};
EXPORT_SYMBOL(fsg_ss_bulk_in_desc);
struct usb_ss_ep_comp_descriptor fsg_ss_bulk_in_comp_desc = {
.bLength = sizeof(fsg_ss_bulk_in_comp_desc),
.bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
/*.bMaxBurst = DYNAMIC, */
};
EXPORT_SYMBOL(fsg_ss_bulk_in_comp_desc);
struct usb_endpoint_descriptor fsg_ss_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(1024),
};
EXPORT_SYMBOL(fsg_ss_bulk_out_desc);
struct usb_ss_ep_comp_descriptor fsg_ss_bulk_out_comp_desc = {
.bLength = sizeof(fsg_ss_bulk_in_comp_desc),
.bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
/*.bMaxBurst = DYNAMIC, */
};
EXPORT_SYMBOL(fsg_ss_bulk_out_comp_desc);
struct usb_descriptor_header *fsg_ss_function[] = {
(struct usb_descriptor_header *) &fsg_intf_desc,
(struct usb_descriptor_header *) &fsg_ss_bulk_in_desc,
(struct usb_descriptor_header *) &fsg_ss_bulk_in_comp_desc,
(struct usb_descriptor_header *) &fsg_ss_bulk_out_desc,
(struct usb_descriptor_header *) &fsg_ss_bulk_out_comp_desc,
NULL,
};
EXPORT_SYMBOL(fsg_ss_function);
/*-------------------------------------------------------------------------*/
/*
* If the next two routines are called while the gadget is registered,
* the caller must own fsg->filesem for writing.
*/
void fsg_lun_close(struct fsg_lun *curlun)
{
if (curlun->filp) {
LDBG(curlun, "close backing file\n");
fput(curlun->filp);
curlun->filp = NULL;
}
}
EXPORT_SYMBOL(fsg_lun_close);
int fsg_lun_open(struct fsg_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;
unsigned int blkbits;
unsigned int blksize;
/* R/W if we can, R/O if we must */
ro = curlun->initially_ro;
if (!ro) {
filp = filp_open(filename, O_RDWR | O_LARGEFILE, 0);
if (PTR_ERR(filp) == -EROFS || PTR_ERR(filp) == -EACCES)
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;
inode = file_inode(filp);
if ((!S_ISREG(inode->i_mode) && !S_ISBLK(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->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;
}
usb: gadget: storage: adapt logic block size to bound block devices Now the mass storage driver has fixed logic block size of 512 bytes. The mass storage gadget read/write bound devices only through VFS, so the bottom level devices actually are just RAW devices to the driver and connected PC. As a RAW, hosts can always format, read and write it right in 512 bytes logic block and don't care about the actual logic block size of devices bound to the gadget. But if we want to share the bound block device partition between target board and PC, in case the logic block size of the bound block device is 4KB, we execute the following steps: 1. connect a board with mass storage gadget to PC(the board has set one partition of on-board block device as file name of the mass storage) 2. PC format the mass storage to VFAT by default logic block size and read/write it 3. disconnect boards from PC 4. target board mount the partition as VFAT Step 4 will fail since kernel on target thinks the logic block size of the bound partition as 4KB. A typical error is "FAT: logical sector size too small for device (logical sector size = 512)" If we execute opposite steps: 1. format the partition to VFAT on target board and read/write this partition 2. connect the board to Windows PC as usb mass storage gadget, windows will think the disk is not formatted So the conclusion is that only as a gadget, the mass storage driver has no any problem. But being shared VFAT or other filesystem on PC and target board, it will fail. This patch adapts logic block size to bound block devices and fix the issue. Cc: Michal Nazarewicz <mina86@mina86.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Peiyu Li <peiyu.li@csr.com> Signed-off-by: Xianglong Du <xianglong.du@csr.com> Signed-off-by: Huayi Li <huayi.li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Felipe Balbi <balbi@ti.com>
2011-08-17 23:52:59 -06:00
if (curlun->cdrom) {
blksize = 2048;
blkbits = 11;
usb: gadget: storage: adapt logic block size to bound block devices Now the mass storage driver has fixed logic block size of 512 bytes. The mass storage gadget read/write bound devices only through VFS, so the bottom level devices actually are just RAW devices to the driver and connected PC. As a RAW, hosts can always format, read and write it right in 512 bytes logic block and don't care about the actual logic block size of devices bound to the gadget. But if we want to share the bound block device partition between target board and PC, in case the logic block size of the bound block device is 4KB, we execute the following steps: 1. connect a board with mass storage gadget to PC(the board has set one partition of on-board block device as file name of the mass storage) 2. PC format the mass storage to VFAT by default logic block size and read/write it 3. disconnect boards from PC 4. target board mount the partition as VFAT Step 4 will fail since kernel on target thinks the logic block size of the bound partition as 4KB. A typical error is "FAT: logical sector size too small for device (logical sector size = 512)" If we execute opposite steps: 1. format the partition to VFAT on target board and read/write this partition 2. connect the board to Windows PC as usb mass storage gadget, windows will think the disk is not formatted So the conclusion is that only as a gadget, the mass storage driver has no any problem. But being shared VFAT or other filesystem on PC and target board, it will fail. This patch adapts logic block size to bound block devices and fix the issue. Cc: Michal Nazarewicz <mina86@mina86.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Peiyu Li <peiyu.li@csr.com> Signed-off-by: Xianglong Du <xianglong.du@csr.com> Signed-off-by: Huayi Li <huayi.li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Felipe Balbi <balbi@ti.com>
2011-08-17 23:52:59 -06:00
} else if (inode->i_bdev) {
blksize = bdev_logical_block_size(inode->i_bdev);
blkbits = blksize_bits(blksize);
usb: gadget: storage: adapt logic block size to bound block devices Now the mass storage driver has fixed logic block size of 512 bytes. The mass storage gadget read/write bound devices only through VFS, so the bottom level devices actually are just RAW devices to the driver and connected PC. As a RAW, hosts can always format, read and write it right in 512 bytes logic block and don't care about the actual logic block size of devices bound to the gadget. But if we want to share the bound block device partition between target board and PC, in case the logic block size of the bound block device is 4KB, we execute the following steps: 1. connect a board with mass storage gadget to PC(the board has set one partition of on-board block device as file name of the mass storage) 2. PC format the mass storage to VFAT by default logic block size and read/write it 3. disconnect boards from PC 4. target board mount the partition as VFAT Step 4 will fail since kernel on target thinks the logic block size of the bound partition as 4KB. A typical error is "FAT: logical sector size too small for device (logical sector size = 512)" If we execute opposite steps: 1. format the partition to VFAT on target board and read/write this partition 2. connect the board to Windows PC as usb mass storage gadget, windows will think the disk is not formatted So the conclusion is that only as a gadget, the mass storage driver has no any problem. But being shared VFAT or other filesystem on PC and target board, it will fail. This patch adapts logic block size to bound block devices and fix the issue. Cc: Michal Nazarewicz <mina86@mina86.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Peiyu Li <peiyu.li@csr.com> Signed-off-by: Xianglong Du <xianglong.du@csr.com> Signed-off-by: Huayi Li <huayi.li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Felipe Balbi <balbi@ti.com>
2011-08-17 23:52:59 -06:00
} else {
blksize = 512;
blkbits = 9;
usb: gadget: storage: adapt logic block size to bound block devices Now the mass storage driver has fixed logic block size of 512 bytes. The mass storage gadget read/write bound devices only through VFS, so the bottom level devices actually are just RAW devices to the driver and connected PC. As a RAW, hosts can always format, read and write it right in 512 bytes logic block and don't care about the actual logic block size of devices bound to the gadget. But if we want to share the bound block device partition between target board and PC, in case the logic block size of the bound block device is 4KB, we execute the following steps: 1. connect a board with mass storage gadget to PC(the board has set one partition of on-board block device as file name of the mass storage) 2. PC format the mass storage to VFAT by default logic block size and read/write it 3. disconnect boards from PC 4. target board mount the partition as VFAT Step 4 will fail since kernel on target thinks the logic block size of the bound partition as 4KB. A typical error is "FAT: logical sector size too small for device (logical sector size = 512)" If we execute opposite steps: 1. format the partition to VFAT on target board and read/write this partition 2. connect the board to Windows PC as usb mass storage gadget, windows will think the disk is not formatted So the conclusion is that only as a gadget, the mass storage driver has no any problem. But being shared VFAT or other filesystem on PC and target board, it will fail. This patch adapts logic block size to bound block devices and fix the issue. Cc: Michal Nazarewicz <mina86@mina86.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Peiyu Li <peiyu.li@csr.com> Signed-off-by: Xianglong Du <xianglong.du@csr.com> Signed-off-by: Huayi Li <huayi.li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Felipe Balbi <balbi@ti.com>
2011-08-17 23:52:59 -06:00
}
num_sectors = size >> blkbits; /* File size in logic-block-size blocks */
min_sectors = 1;
if (curlun->cdrom) {
usb: gadget: storage: adapt logic block size to bound block devices Now the mass storage driver has fixed logic block size of 512 bytes. The mass storage gadget read/write bound devices only through VFS, so the bottom level devices actually are just RAW devices to the driver and connected PC. As a RAW, hosts can always format, read and write it right in 512 bytes logic block and don't care about the actual logic block size of devices bound to the gadget. But if we want to share the bound block device partition between target board and PC, in case the logic block size of the bound block device is 4KB, we execute the following steps: 1. connect a board with mass storage gadget to PC(the board has set one partition of on-board block device as file name of the mass storage) 2. PC format the mass storage to VFAT by default logic block size and read/write it 3. disconnect boards from PC 4. target board mount the partition as VFAT Step 4 will fail since kernel on target thinks the logic block size of the bound partition as 4KB. A typical error is "FAT: logical sector size too small for device (logical sector size = 512)" If we execute opposite steps: 1. format the partition to VFAT on target board and read/write this partition 2. connect the board to Windows PC as usb mass storage gadget, windows will think the disk is not formatted So the conclusion is that only as a gadget, the mass storage driver has no any problem. But being shared VFAT or other filesystem on PC and target board, it will fail. This patch adapts logic block size to bound block devices and fix the issue. Cc: Michal Nazarewicz <mina86@mina86.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Peiyu Li <peiyu.li@csr.com> Signed-off-by: Xianglong Du <xianglong.du@csr.com> Signed-off-by: Huayi Li <huayi.li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Felipe Balbi <balbi@ti.com>
2011-08-17 23:52:59 -06:00
min_sectors = 300; /* Smallest track is 300 frames */
if (num_sectors >= 256*60*75) {
num_sectors = 256*60*75 - 1;
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;
}
if (fsg_lun_is_open(curlun))
fsg_lun_close(curlun);
curlun->blksize = blksize;
curlun->blkbits = blkbits;
curlun->ro = ro;
curlun->filp = filp;
curlun->file_length = size;
curlun->num_sectors = num_sectors;
LDBG(curlun, "open backing file: %s\n", filename);
return 0;
out:
fput(filp);
return rc;
}
EXPORT_SYMBOL(fsg_lun_open);
/*-------------------------------------------------------------------------*/
/*
* Sync the file data, don't bother with the metadata.
* This code was copied from fs/buffer.c:sys_fdatasync().
*/
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);
}
EXPORT_SYMBOL(fsg_lun_fsync_sub);
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);
}
}
EXPORT_SYMBOL(store_cdrom_address);
/*-------------------------------------------------------------------------*/
ssize_t fsg_show_ro(struct fsg_lun *curlun, char *buf)
{
return sprintf(buf, "%d\n", fsg_lun_is_open(curlun)
? curlun->ro
: curlun->initially_ro);
}
EXPORT_SYMBOL(fsg_show_ro);
ssize_t fsg_show_nofua(struct fsg_lun *curlun, char *buf)
{
return sprintf(buf, "%u\n", curlun->nofua);
}
EXPORT_SYMBOL(fsg_show_nofua);
ssize_t fsg_show_file(struct fsg_lun *curlun, struct rw_semaphore *filesem,
char *buf)
{
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;
}
EXPORT_SYMBOL(fsg_show_file);
ssize_t fsg_show_cdrom(struct fsg_lun *curlun, char *buf)
{
return sprintf(buf, "%u\n", curlun->cdrom);
}
EXPORT_SYMBOL(fsg_show_cdrom);
ssize_t fsg_show_removable(struct fsg_lun *curlun, char *buf)
{
return sprintf(buf, "%u\n", curlun->removable);
}
EXPORT_SYMBOL(fsg_show_removable);
/*
* The caller must hold fsg->filesem for reading when calling this function.
*/
static ssize_t _fsg_store_ro(struct fsg_lun *curlun, bool ro)
{
if (fsg_lun_is_open(curlun)) {
LDBG(curlun, "read-only status change prevented\n");
return -EBUSY;
}
curlun->ro = ro;
curlun->initially_ro = ro;
LDBG(curlun, "read-only status set to %d\n", curlun->ro);
return 0;
}
ssize_t fsg_store_ro(struct fsg_lun *curlun, struct rw_semaphore *filesem,
const char *buf, size_t count)
{
ssize_t rc;
bool ro;
rc = strtobool(buf, &ro);
if (rc)
return rc;
/*
* Allow the write-enable status to change only while the
* backing file is closed.
*/
down_read(filesem);
rc = _fsg_store_ro(curlun, ro);
if (!rc)
rc = count;
up_read(filesem);
return rc;
}
EXPORT_SYMBOL(fsg_store_ro);
ssize_t fsg_store_nofua(struct fsg_lun *curlun, const char *buf, size_t count)
{
bool nofua;
int ret;
ret = strtobool(buf, &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;
}
EXPORT_SYMBOL(fsg_store_nofua);
ssize_t fsg_store_file(struct fsg_lun *curlun, struct rw_semaphore *filesem,
const char *buf, size_t count)
{
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);
}
EXPORT_SYMBOL(fsg_store_file);
ssize_t fsg_store_cdrom(struct fsg_lun *curlun, struct rw_semaphore *filesem,
const char *buf, size_t count)
{
bool cdrom;
int ret;
ret = strtobool(buf, &cdrom);
if (ret)
return ret;
down_read(filesem);
ret = cdrom ? _fsg_store_ro(curlun, true) : 0;
if (!ret) {
curlun->cdrom = cdrom;
ret = count;
}
up_read(filesem);
return ret;
}
EXPORT_SYMBOL(fsg_store_cdrom);
ssize_t fsg_store_removable(struct fsg_lun *curlun, const char *buf,
size_t count)
{
bool removable;
int ret;
ret = strtobool(buf, &removable);
if (ret)
return ret;
curlun->removable = removable;
return count;
}
EXPORT_SYMBOL(fsg_store_removable);
MODULE_LICENSE("GPL");