/**************************************************************************** * drivers/mtd/ftl.c * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. The * ASF licenses this file to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance with the * License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* Check if read/write buffer support is needed */ #if defined(CONFIG_FTL_READAHEAD) || defined(CONFIG_FTL_WRITEBUFFER) # define FTL_HAVE_RWBUFFER 1 #endif /* The maximum length of the device name paths is the maximum length of a * name plus 5 for the the length of "/dev/" and a NUL terminator. */ #define DEV_NAME_MAX (NAME_MAX + 5) /**************************************************************************** * Private Types ****************************************************************************/ struct ftl_struct_s { FAR struct mtd_dev_s *mtd; /* Contained MTD interface */ struct mtd_geometry_s geo; /* Device geometry */ #ifdef FTL_HAVE_RWBUFFER struct rwbuffer_s rwb; /* Read-ahead/write buffer support */ #endif uint16_t blkper; /* R/W blocks per erase block */ uint16_t refs; /* Number of references */ bool unlinked; /* The driver has been unlinked */ FAR uint8_t *eblock; /* One, in-memory erase block */ }; /**************************************************************************** * Private Function Prototypes ****************************************************************************/ static int ftl_open(FAR struct inode *inode); static int ftl_close(FAR struct inode *inode); static ssize_t ftl_reload(FAR void *priv, FAR uint8_t *buffer, off_t startblock, size_t nblocks); static ssize_t ftl_read(FAR struct inode *inode, FAR unsigned char *buffer, blkcnt_t start_sector, unsigned int nsectors); static ssize_t ftl_flush(FAR void *priv, FAR const uint8_t *buffer, off_t startblock, size_t nblocks); static ssize_t ftl_write(FAR struct inode *inode, FAR const unsigned char *buffer, blkcnt_t start_sector, unsigned int nsectors); static int ftl_geometry(FAR struct inode *inode, FAR struct geometry *geometry); static int ftl_ioctl(FAR struct inode *inode, int cmd, unsigned long arg); #ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS static int ftl_unlink(FAR struct inode *inode); #endif /**************************************************************************** * Private Data ****************************************************************************/ static const struct block_operations g_bops = { ftl_open, /* open */ ftl_close, /* close */ ftl_read, /* read */ ftl_write, /* write */ ftl_geometry, /* geometry */ ftl_ioctl /* ioctl */ #ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS , ftl_unlink /* unlink */ #endif }; /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: ftl_open * * Description: Open the block device * ****************************************************************************/ static int ftl_open(FAR struct inode *inode) { FAR struct ftl_struct_s *dev; DEBUGASSERT(inode && inode->i_private); dev = (FAR struct ftl_struct_s *)inode->i_private; dev->refs++; return OK; } /**************************************************************************** * Name: ftl_close * * Description: close the block device * ****************************************************************************/ static int ftl_close(FAR struct inode *inode) { FAR struct ftl_struct_s *dev; DEBUGASSERT(inode && inode->i_private); dev = (FAR struct ftl_struct_s *)inode->i_private; #ifdef CONFIG_FTL_WRITEBUFFER rwb_flush(&dev->rwb); #endif if (--dev->refs == 0 && dev->unlinked) { #ifdef FTL_HAVE_RWBUFFER rwb_uninitialize(&dev->rwb); #endif if (dev->eblock) { kmm_free(dev->eblock); } kmm_free(dev); } return OK; } /**************************************************************************** * Name: ftl_reload * * Description: Read the specified number of sectors * ****************************************************************************/ static ssize_t ftl_reload(FAR void *priv, FAR uint8_t *buffer, off_t startblock, size_t nblocks) { struct ftl_struct_s *dev = (struct ftl_struct_s *)priv; ssize_t nread; /* Read the full erase block into the buffer */ nread = MTD_BREAD(dev->mtd, startblock, nblocks, buffer); if (nread != nblocks) { ferr("ERROR: Read %zu blocks starting at block %" PRIdOFF " failed: %zd\n", nblocks, startblock, nread); } return nread; } /**************************************************************************** * Name: ftl_read * * Description: Read the specified number of sectors * ****************************************************************************/ static ssize_t ftl_read(FAR struct inode *inode, unsigned char *buffer, blkcnt_t start_sector, unsigned int nsectors) { FAR struct ftl_struct_s *dev; finfo("sector: %" PRIuOFF " nsectors: %u\n", start_sector, nsectors); DEBUGASSERT(inode && inode->i_private); dev = (FAR struct ftl_struct_s *)inode->i_private; #ifdef FTL_HAVE_RWBUFFER return rwb_read(&dev->rwb, start_sector, nsectors, buffer); #else return ftl_reload(dev, buffer, start_sector, nsectors); #endif } /**************************************************************************** * Name: ftl_flush * * Description: Write the specified number of sectors * ****************************************************************************/ static int ftl_alloc_eblock(FAR struct ftl_struct_s *dev) { if (dev->eblock == NULL) { /* Allocate one, in-memory erase block buffer */ dev->eblock = (FAR uint8_t *)kmm_malloc(dev->geo.erasesize); } return dev->eblock != NULL ? OK : -ENOMEM; } static ssize_t ftl_flush(FAR void *priv, FAR const uint8_t *buffer, off_t startblock, size_t nblocks) { struct ftl_struct_s *dev = (struct ftl_struct_s *)priv; off_t alignedblock; off_t mask; off_t rwblock; off_t eraseblock; off_t offset; size_t remaining; size_t nxfrd; int nbytes; int ret; /* Get the aligned block. Here is is assumed: (1) The number of R/W blocks * per erase block is a power of 2, and (2) the erase begins with that same * alignment. */ mask = dev->blkper - 1; alignedblock = (startblock + mask) & ~mask; /* Handle partial erase blocks before the first unaligned block */ remaining = nblocks; if (alignedblock > startblock) { /* Check if the write is shorter than to the end of the erase block */ bool short_write = (remaining < (alignedblock - startblock)); ret = ftl_alloc_eblock(dev); if (ret < 0) { ferr("ERROR: Failed to allocate an erase block buffer\n"); return ret; } /* Read the full erase block into the buffer */ rwblock = startblock & ~mask; nxfrd = MTD_BREAD(dev->mtd, rwblock, dev->blkper, dev->eblock); if (nxfrd != dev->blkper) { ferr("ERROR: Read erase block %" PRIdOFF " failed: %zd\n", rwblock, nxfrd); return -EIO; } /* Then erase the erase block */ eraseblock = rwblock / dev->blkper; ret = MTD_ERASE(dev->mtd, eraseblock, 1); if (ret < 0) { ferr("ERROR: Erase block=%" PRIdOFF "failed: %d\n", eraseblock, ret); return ret; } /* Copy the user data at the end of the buffered erase block */ offset = (startblock & mask) * dev->geo.blocksize; if (short_write) { nbytes = remaining * dev->geo.blocksize; } else { nbytes = dev->geo.erasesize - offset; } finfo("Copy %d bytes into erase block=%" PRIdOFF " at offset=%" PRIdOFF "\n", nbytes, eraseblock, offset); memcpy(dev->eblock + offset, buffer, nbytes); /* And write the erase block back to flash */ nxfrd = MTD_BWRITE(dev->mtd, rwblock, dev->blkper, dev->eblock); if (nxfrd != dev->blkper) { ferr("ERROR: Write erase block %" PRIdOFF " failed: %zu\n", rwblock, nxfrd); return -EIO; } /* Then update for amount written */ if (short_write) { remaining = 0; } else { remaining -= dev->blkper - (startblock & mask); } buffer += nbytes; } /* How handle full erase pages in the middle */ while (remaining >= dev->blkper) { /* Erase the erase block */ eraseblock = alignedblock / dev->blkper; ret = MTD_ERASE(dev->mtd, eraseblock, 1); if (ret < 0) { ferr("ERROR: Erase block=%" PRIdOFF " failed: %d\n", eraseblock, ret); return ret; } /* Write a full erase back to flash */ finfo("Write %" PRId32 " bytes into erase block=%" PRIdOFF " at offset=0\n", dev->geo.erasesize, alignedblock); nxfrd = MTD_BWRITE(dev->mtd, alignedblock, dev->blkper, buffer); if (nxfrd != dev->blkper) { ferr("ERROR: Write erase block %" PRIdOFF " failed: %zu\n", alignedblock, nxfrd); return -EIO; } /* Then update for amount written */ alignedblock += dev->blkper; remaining -= dev->blkper; buffer += dev->geo.erasesize; } /* Finally, handle any partial blocks after the last full erase block */ if (remaining > 0) { ret = ftl_alloc_eblock(dev); if (ret < 0) { ferr("ERROR: Failed to allocate an erase block buffer\n"); return ret; } /* Read the full erase block into the buffer */ nxfrd = MTD_BREAD(dev->mtd, alignedblock, dev->blkper, dev->eblock); if (nxfrd != dev->blkper) { ferr("ERROR: Read erase block %" PRIdOFF " failed: %zu\n", alignedblock, nxfrd); return -EIO; } /* Then erase the erase block */ eraseblock = alignedblock / dev->blkper; ret = MTD_ERASE(dev->mtd, eraseblock, 1); if (ret < 0) { ferr("ERROR: Erase block=%" PRIdOFF "failed: %d\n", eraseblock, ret); return ret; } /* Copy the user data at the beginning the buffered erase block */ nbytes = remaining * dev->geo.blocksize; finfo("Copy %d bytes into erase block=%" PRIdOFF " at offset=0\n", nbytes, alignedblock); memcpy(dev->eblock, buffer, nbytes); /* And write the erase back to flash */ nxfrd = MTD_BWRITE(dev->mtd, alignedblock, dev->blkper, dev->eblock); if (nxfrd != dev->blkper) { ferr("ERROR: Write erase block %" PRIdOFF " failed: %zu\n", alignedblock, nxfrd); return -EIO; } } return nblocks; } /**************************************************************************** * Name: ftl_write * * Description: Write (or buffer) the specified number of sectors * ****************************************************************************/ static ssize_t ftl_write(FAR struct inode *inode, FAR const unsigned char *buffer, blkcnt_t start_sector, unsigned int nsectors) { struct ftl_struct_s *dev; finfo("sector: %" PRIuOFF " nsectors: %u\n", start_sector, nsectors); DEBUGASSERT(inode && inode->i_private); dev = (struct ftl_struct_s *)inode->i_private; #ifdef FTL_HAVE_RWBUFFER return rwb_write(&dev->rwb, start_sector, nsectors, buffer); #else return ftl_flush(dev, buffer, start_sector, nsectors); #endif } /**************************************************************************** * Name: ftl_geometry * * Description: Return device geometry * ****************************************************************************/ static int ftl_geometry(FAR struct inode *inode, FAR struct geometry *geometry) { FAR struct ftl_struct_s *dev; finfo("Entry\n"); DEBUGASSERT(inode); if (geometry) { dev = (struct ftl_struct_s *)inode->i_private; geometry->geo_available = true; geometry->geo_mediachanged = false; geometry->geo_writeenabled = true; geometry->geo_nsectors = dev->geo.neraseblocks * dev->blkper; geometry->geo_sectorsize = dev->geo.blocksize; strlcpy(geometry->geo_model, dev->geo.model, sizeof(geometry->geo_model)); finfo("available: true mediachanged: false writeenabled: %s\n", geometry->geo_writeenabled ? "true" : "false"); finfo("nsectors: %" PRIuOFF " sectorsize: %u\n", geometry->geo_nsectors, geometry->geo_sectorsize); return OK; } return -EINVAL; } /**************************************************************************** * Name: ftl_ioctl * * Description: Return device geometry * ****************************************************************************/ static int ftl_ioctl(FAR struct inode *inode, int cmd, unsigned long arg) { FAR struct ftl_struct_s *dev; int ret; finfo("Entry\n"); DEBUGASSERT(inode && inode->i_private); dev = (struct ftl_struct_s *)inode->i_private; if (cmd == BIOC_FLUSH) { #ifdef CONFIG_FTL_WRITEBUFFER rwb_flush(&dev->rwb); #endif } /* No other block driver ioctl commands are not recognized by this * driver. Other possible MTD driver ioctl commands are passed through * to the MTD driver (unchanged). */ ret = MTD_IOCTL(dev->mtd, cmd, arg); if (ret < 0 && ret != -ENOTTY) { ferr("ERROR: MTD ioctl(%04x) failed: %d\n", cmd, ret); } return ret; } /**************************************************************************** * Name: ftl_unlink * * Description: Unlink the device * ****************************************************************************/ #ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS static int ftl_unlink(FAR struct inode *inode) { FAR struct ftl_struct_s *dev; DEBUGASSERT(inode && inode->i_private); dev = (FAR struct ftl_struct_s *)inode->i_private; dev->unlinked = true; if (dev->refs == 0) { #ifdef FTL_HAVE_RWBUFFER rwb_uninitialize(&dev->rwb); #endif if (dev->eblock) { kmm_free(dev->eblock); } kmm_free(dev); } return OK; } #endif /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: ftl_initialize_by_path * * Description: * Initialize to provide a block driver wrapper around an MTD interface * * Input Parameters: * path - The block device path. * mtd - The MTD device that supports the FLASH interface. * ****************************************************************************/ int ftl_initialize_by_path(FAR const char *path, FAR struct mtd_dev_s *mtd) { struct ftl_struct_s *dev; int ret = -ENOMEM; /* Sanity check */ if (path == NULL || mtd == NULL) { return -EINVAL; } finfo("path=\"%s\"\n", path); /* Allocate a FTL device structure */ dev = (FAR struct ftl_struct_s *)kmm_zalloc(sizeof(struct ftl_struct_s)); if (dev) { /* Initialize the FTL device structure */ dev->mtd = mtd; /* Get the device geometry. (casting to uintptr_t first eliminates * complaints on some architectures where the sizeof long is different * from the size of a pointer). */ ret = MTD_IOCTL(mtd, MTDIOC_GEOMETRY, (unsigned long)((uintptr_t)&dev->geo)); if (ret < 0) { ferr("ERROR: MTD ioctl(MTDIOC_GEOMETRY) failed: %d\n", ret); kmm_free(dev); return ret; } /* Get the number of R/W blocks per erase block */ dev->blkper = dev->geo.erasesize / dev->geo.blocksize; DEBUGASSERT(dev->blkper * dev->geo.blocksize == dev->geo.erasesize); /* Configure read-ahead/write buffering */ #ifdef FTL_HAVE_RWBUFFER dev->rwb.blocksize = dev->geo.blocksize; dev->rwb.nblocks = dev->geo.neraseblocks * dev->blkper; dev->rwb.dev = (FAR void *)dev; dev->rwb.wrflush = ftl_flush; dev->rwb.rhreload = ftl_reload; #if defined(CONFIG_FTL_WRITEBUFFER) dev->rwb.wrmaxblocks = dev->blkper; dev->rwb.wralignblocks = dev->blkper; #endif #ifdef CONFIG_FTL_READAHEAD dev->rwb.rhmaxblocks = dev->blkper; #endif ret = rwb_initialize(&dev->rwb); if (ret < 0) { ferr("ERROR: rwb_initialize failed: %d\n", ret); kmm_free(dev); return ret; } #endif /* Inode private data is a reference to the FTL device structure */ ret = register_blockdriver(path, &g_bops, 0, dev); if (ret < 0) { ferr("ERROR: register_blockdriver failed: %d\n", -ret); #ifdef FTL_HAVE_RWBUFFER rwb_uninitialize(&dev->rwb); #endif kmm_free(dev); } } return ret; } /**************************************************************************** * Name: ftl_initialize * * Description: * Initialize to provide a block driver wrapper around an MTD interface * * Input Parameters: * minor - The minor device number. The MTD block device will be * registered as as /dev/mtdblockN where N is the minor number. * mtd - The MTD device that supports the FLASH interface. * ****************************************************************************/ int ftl_initialize(int minor, FAR struct mtd_dev_s *mtd) { char path[DEV_NAME_MAX]; #ifdef CONFIG_DEBUG_FEATURES /* Sanity check */ if (minor < 0 || minor > 255) { return -EINVAL; } #endif /* Do the real work by ftl_initialize_by_path */ snprintf(path, DEV_NAME_MAX, "/dev/mtdblock%d", minor); return ftl_initialize_by_path(path, mtd); }