diff options
Diffstat (limited to 'nuttx')
| -rw-r--r-- | nuttx/ChangeLog | 2 | ||||
| -rw-r--r-- | nuttx/Documentation/NuttX.html | 1 | ||||
| -rw-r--r-- | nuttx/Documentation/NuttXBanner.html | 2 | ||||
| -rw-r--r-- | nuttx/drivers/Makefile | 2 | ||||
| -rw-r--r-- | nuttx/drivers/loop.c | 353 | ||||
| -rw-r--r-- | nuttx/include/nuttx/fs.h | 6 |
6 files changed, 360 insertions, 6 deletions
diff --git a/nuttx/ChangeLog b/nuttx/ChangeLog index 225347254..110119ca0 100644 --- a/nuttx/ChangeLog +++ b/nuttx/ChangeLog @@ -546,4 +546,4 @@ only controls the size of the stack for the IDLE thread. Added CONFIG_USERMAIN_STACKSIZE: This is the size of stack used with the user_start() thread is created. The two stacks no longer have to be the same. - + * Add a loop device that converts a file into a block device. diff --git a/nuttx/Documentation/NuttX.html b/nuttx/Documentation/NuttX.html index 84ba8a6ef..3f8538cd5 100644 --- a/nuttx/Documentation/NuttX.html +++ b/nuttx/Documentation/NuttX.html @@ -1189,6 +1189,7 @@ nuttx-0.3.18 2008-xx-xx Gregory Nutt <spudmonkey@racsa.co.cr> only controls the size of the stack for the IDLE thread. Added CONFIG_USERMAIN_STACKSIZE: This is the size of stack used with the user_start() thread is created. The two stacks no longer have to be the same. + * Add a loop device that converts a file into a block device. pascal-0.1.3 2008-xx-xx Gregory Nutt <spudmonkey@racsa.co.cr> diff --git a/nuttx/Documentation/NuttXBanner.html b/nuttx/Documentation/NuttXBanner.html index ee9aaeb19..7b83f46ad 100644 --- a/nuttx/Documentation/NuttXBanner.html +++ b/nuttx/Documentation/NuttXBanner.html @@ -30,7 +30,7 @@ </table> </td> <td width="100" valign="top"> - <a href="http://groups.yahoo.com/group/nuttx/join"> + <a href="http://groups.yahoo.com/group/nuttx/join" target="_top"> <img src="http://us.i1.yimg.com/us.yimg.com/i/yg/img/i/us/ui/join.gif" style="border: 0px;" alt="Click to join nuttx"/> diff --git a/nuttx/drivers/Makefile b/nuttx/drivers/Makefile index 33d9c096a..8d03a1918 100644 --- a/nuttx/drivers/Makefile +++ b/nuttx/drivers/Makefile @@ -59,7 +59,7 @@ AOBJS = $(ASRCS:.S=$(OBJEXT)) CSRCS = ifneq ($(CONFIG_NFILE_DESCRIPTORS),0) CSRCS += dev_null.c dev_zero.c pipe.c fifo.c pipe_common.c \ - serial.c serialirq.c lowconsole.c can.c + loop.c serial.c serialirq.c lowconsole.c can.c ifneq ($(CONFIG_DISABLE_MOUNTPOINT),y) CSRCS += ramdisk.c endif diff --git a/nuttx/drivers/loop.c b/nuttx/drivers/loop.c new file mode 100644 index 000000000..79c3795be --- /dev/null +++ b/nuttx/drivers/loop.c @@ -0,0 +1,353 @@ +/**************************************************************************** + * drivers/loop.c + * + * Copyright (C) 2008 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <spudmonkey@racsa.co.cr> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * 3. Neither the name NuttX nor the names of its contributors may be + * used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS + * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED + * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN + * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + ****************************************************************************/ + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> + +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/types.h> +#include <sys/ioctl.h> + +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <string.h> +#include <fcntl.h> +#include <debug.h> +#include <errno.h> + +#include <nuttx/fs.h> + +/**************************************************************************** + * Private Definitions + ****************************************************************************/ + +/**************************************************************************** + * Private Types + ****************************************************************************/ + +struct loop_struct_s +{ + uint32 nsectors; /* Number of sectors on device */ + uint16 sectsize; /* The size of one sector */ +#ifdef CONFIG_FS_WRITABLE + boolean writeenabled; /* TRUE: can write to device */ +#endif + int fd; /* Descriptor of char device/file */ +}; + +/**************************************************************************** + * Private Function Prototypes + ****************************************************************************/ + +static int loop_open(FAR struct inode *inode); +static int loop_close(FAR struct inode *inode); +static ssize_t loop_read(FAR struct inode *inode, unsigned char *buffer, + size_t start_sector, unsigned int nsectors); +#ifdef CONFIG_FS_WRITABLE +static ssize_t loop_write(FAR struct inode *inode, const unsigned char *buffer, + size_t start_sector, unsigned int nsectors); +#endif +static int loop_geometry(FAR struct inode *inode, struct geometry *geometry); + +/**************************************************************************** + * Private Data + ****************************************************************************/ + +static const struct block_operations g_bops = +{ + loop_open, /* open */ + loop_close, /* close */ + loop_read, /* read */ +#ifdef CONFIG_FS_WRITABLE + loop_write, /* write */ +#else + NULL, /* write */ +#endif + loop_geometry, /* geometry */ + NULL /* ioctl */ +}; + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: loop_open + * + * Description: Open the block device + * + ****************************************************************************/ + +static int loop_open(FAR struct inode *inode) +{ + return OK; +} + +/**************************************************************************** + * Name: loop_closel + * + * Description: close the block device + * + ****************************************************************************/ + +static int loop_close(FAR struct inode *inode) +{ + return OK; +} + +/**************************************************************************** + * Name: loop_read + * + * Description: Read the specified numer of sectors + * + ****************************************************************************/ + +static ssize_t loop_read(FAR struct inode *inode, unsigned char *buffer, + size_t start_sector, unsigned int nsectors) +{ + struct loop_struct_s *dev; + size_t nbytesread; + off_t offset; + int ret; + + DEBUGASSERT(inode && inode->i_private); + dev = (struct loop_struct_s *)inode->i_private; + + /* Calculate the offset to read the sectors and seek to the position */ + + offset = start_sector * dev->sectsize; + ret = lseek(dev->fd, offset, SEEK_SET); + if (ret == (off_t)-1) + { + dbg("Seek failed for offset=%d: %d\n", (int)offset, errno); + } + + /* Then read the requested number of sectors from that position */ + + do + { + nbytesread = read(dev->fd, buffer, nsectors * dev->sectsize); + if (nbytesread < 0 && errno != EINTR) + { + dbg("Read failed: %d\n", errno); + return -errno; + } + } + while (nbytesread < 0); + + /* Return the number of sectors read */ + + return nbytesread / dev->sectsize; +} + +/**************************************************************************** + * Name: loop_write + * + * Description: Write the specified number of sectors + * + ****************************************************************************/ + +#ifdef CONFIG_FS_WRITABLE +static ssize_t loop_write(FAR struct inode *inode, const unsigned char *buffer, + size_t start_sector, unsigned int nsectors) +{ + struct loop_struct_s *dev; + size_t nbyteswritten; + off_t offset; + int ret; + + DEBUGASSERT(inode && inode->i_private); + dev = (struct loop_struct_s *)inode->i_private; + + /* Calculate the offset to write the sectors and seek to the position */ + + offset = start_sector * dev->sectsize; + ret = lseek(dev->fd, offset, SEEK_SET); + if (ret == (off_t)-1) + { + dbg("Seek failed for offset=%d: %d\n", (int)offset, errno); + } + + /* Then write the requested number of sectors to that position */ + + do + { + nbyteswritten = write(dev->fd, buffer, nsectors * dev->sectsize); + if (nbyteswritten < 0 && errno != EINTR) + { + dbg("Write failed: %d\n", errno); + return -errno; + } + } + while (nbyteswritten < 0); + + /* Return the number of sectors written */ + + return nbyteswritten / dev->sectsize; +} +#endif + +/**************************************************************************** + * Name: loop_geometry + * + * Description: Return device geometry + * + ****************************************************************************/ + +static int loop_geometry(FAR struct inode *inode, struct geometry *geometry) +{ + struct loop_struct_s *dev; + + DEBUGASSERT(inode); + if (geometry) + { + dev = (struct loop_struct_s *)inode->i_private; + geometry->geo_available = TRUE; + geometry->geo_mediachanged = FALSE; +#ifdef CONFIG_FS_WRITABLE + geometry->geo_writeenabled = dev->writeenabled; +#else + geometry->geo_writeenabled = FALSE; +#endif + geometry->geo_nsectors = dev->nsectors; + geometry->geo_sectorsize = dev->sectsize; + return OK; + } + return -EINVAL; +} + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: losetup + * + * Description: + * Setup the loop device so that it exports the file referenced by 'name' + * as a block device. + * + ****************************************************************************/ + +int losetup(const char *name, int minor, uint16 sectsize) +{ + struct loop_struct_s *dev; + struct stat sb; + char devname[16]; + int ret; + + /* Sanity check */ + +#ifdef CONFIG_DEBUG + if (minor < 0 || minor > 255 || !name || !sectsize) + { + return -EINVAL; + } +#endif + + /* Get the size of the file */ + + ret = stat(name, &sb); + if (ret < 0) + { + dbg("Failed to stat %s: %d\n", name, errno); + return -errno; + } + + /* Check if the file system is big enough for one block */ + + if (sb.st_size < sectsize) + { + dbg("File is too small for blocksize\n"); + return -ERANGE; + } + + /* Allocate a loop device structure */ + + dev = (struct loop_struct_s *)malloc(sizeof(struct loop_struct_s)); + if (!dev) + { + return -ENOMEM; + } + + /* Open the file. First try to open the device W/R */ + +#ifdef CONFIG_FS_WRITABLE + dev->writeenabled = FALSE; /* Assume failure */ + + dev->fd = open(name, O_RDWR); + if (dev->fd >= 0) + { + dev->writeenabled = TRUE; /* Success */ + } + else +#endif + { + /* If that fails, then try to open the device read-only */ + + dev->fd = open(name, O_RDWR); + if (dev->fd < 0) + { + dbg("Failed to open %s: %d\n", name, errno); + free(dev); + return -errno; + } + } + + /* Initialize the remaining fields */ + + dev->nsectors = sb.st_size / sectsize; /* Number of sectors on device */ + dev->sectsize = sectsize; /* The size of one sector */ + + /* Create a loop device name */ + + snprintf(devname, 16, "/dev/loop%d", minor); + + /* Inode private data is a reference to the loop device stgructure */ + + ret = register_blockdriver(devname, &g_bops, 0, dev); + if (ret < 0) + { + fdbg("register_blockdriver failed: %d\n", -ret); + free(dev); + } + + return ret; +} diff --git a/nuttx/include/nuttx/fs.h b/nuttx/include/nuttx/fs.h index 2c933804d..6d5dd7861 100644 --- a/nuttx/include/nuttx/fs.h +++ b/nuttx/include/nuttx/fs.h @@ -366,12 +366,12 @@ EXTERN int lib_flushall(FAR struct streamlist *list); /* drivers ******************************************************************/ -/* Call in of these to register the corresponding default - * default drivers in the drivers/ subdirectory +/* Call any of these to register the corresponding drivers in the drivers/ + * subdirectory */ EXTERN void devnull_register(void); - +EXTERN int losetup(const char *name, int minor, uint16 sectsize); #undef EXTERN #if defined(__cplusplus) |