| /* |
| * MTD device concatenation layer |
| * |
| * Copyright © 2002 Robert Kaiser <rkaiser@sysgo.de> |
| * Copyright © 2002-2010 David Woodhouse <dwmw2@infradead.org> |
| * |
| * NAND support by Christian Gan <cgan@iders.ca> |
| * |
| * 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 program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| * |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/slab.h> |
| #include <linux/sched.h> |
| #include <linux/types.h> |
| #include <linux/backing-dev.h> |
| |
| #include <linux/mtd/mtd.h> |
| #include <linux/mtd/concat.h> |
| |
| #include <asm/div64.h> |
| |
| /* |
| * Our storage structure: |
| * Subdev points to an array of pointers to struct mtd_info objects |
| * which is allocated along with this structure |
| * |
| */ |
| struct mtd_concat { |
| struct mtd_info mtd; |
| int num_subdev; |
| struct mtd_info **subdev; |
| }; |
| |
| /* |
| * how to calculate the size required for the above structure, |
| * including the pointer array subdev points to: |
| */ |
| #define SIZEOF_STRUCT_MTD_CONCAT(num_subdev) \ |
| ((sizeof(struct mtd_concat) + (num_subdev) * sizeof(struct mtd_info *))) |
| |
| /* |
| * Given a pointer to the MTD object in the mtd_concat structure, |
| * we can retrieve the pointer to that structure with this macro. |
| */ |
| #define CONCAT(x) ((struct mtd_concat *)(x)) |
| |
| /* |
| * MTD methods which look up the relevant subdevice, translate the |
| * effective address and pass through to the subdevice. |
| */ |
| |
| static int |
| concat_read(struct mtd_info *mtd, loff_t from, size_t len, |
| size_t * retlen, u_char * buf) |
| { |
| struct mtd_concat *concat = CONCAT(mtd); |
| int ret = 0, err; |
| int i; |
| |
| *retlen = 0; |
| |
| for (i = 0; i < concat->num_subdev; i++) { |
| struct mtd_info *subdev = concat->subdev[i]; |
| size_t size, retsize; |
| |
| if (from >= subdev->size) { |
| /* Not destined for this subdev */ |
| size = 0; |
| from -= subdev->size; |
| continue; |
| } |
| if (from + len > subdev->size) |
| /* First part goes into this subdev */ |
| size = subdev->size - from; |
| else |
| /* Entire transaction goes into this subdev */ |
| size = len; |
| |
| err = mtd_read(subdev, from, size, &retsize, buf); |
| |
| /* Save information about bitflips! */ |
| if (unlikely(err)) { |
| if (mtd_is_eccerr(err)) { |
| mtd->ecc_stats.failed++; |
| ret = err; |
| } else if (mtd_is_bitflip(err)) { |
| mtd->ecc_stats.corrected++; |
| /* Do not overwrite -EBADMSG !! */ |
| if (!ret) |
| ret = err; |
| } else |
| return err; |
| } |
| |
| *retlen += retsize; |
| len -= size; |
| if (len == 0) |
| return ret; |
| |
| buf += size; |
| from = 0; |
| } |
| return -EINVAL; |
| } |
| |
| static int |
| concat_write(struct mtd_info *mtd, loff_t to, size_t len, |
| size_t * retlen, const u_char * buf) |
| { |
| struct mtd_concat *concat = CONCAT(mtd); |
| int err = -EINVAL; |
| int i; |
| |
| if (!(mtd->flags & MTD_WRITEABLE)) |
| return -EROFS; |
| |
| *retlen = 0; |
| |
| for (i = 0; i < concat->num_subdev; i++) { |
| struct mtd_info *subdev = concat->subdev[i]; |
| size_t size, retsize; |
| |
| if (to >= subdev->size) { |
| size = 0; |
| to -= subdev->size; |
| continue; |
| } |
| if (to + len > subdev->size) |
| size = subdev->size - to; |
| else |
| size = len; |
| |
| if (!(subdev->flags & MTD_WRITEABLE)) |
| err = -EROFS; |
| else |
| err = mtd_write(subdev, to, size, &retsize, buf); |
| |
| if (err) |
| break; |
| |
| *retlen += retsize; |
| len -= size; |
| if (len == 0) |
| break; |
| |
| err = -EINVAL; |
| buf += size; |
| to = 0; |
| } |
| return err; |
| } |
| |
| static int |
| concat_writev(struct mtd_info *mtd, const struct kvec *vecs, |
| unsigned long count, loff_t to, size_t * retlen) |
| { |
| struct mtd_concat *concat = CONCAT(mtd); |
| struct kvec *vecs_copy; |
| unsigned long entry_low, entry_high; |
| size_t total_len = 0; |
| int i; |
| int err = -EINVAL; |
| |
| if (!(mtd->flags & MTD_WRITEABLE)) |
| return -EROFS; |
| |
| *retlen = 0; |
| |
| /* Calculate total length of data */ |
| for (i = 0; i < count; i++) |
| total_len += vecs[i].iov_len; |
| |
| /* Do not allow write past end of device */ |
| if ((to + total_len) > mtd->size) |
| return -EINVAL; |
| |
| /* Check alignment */ |
| if (mtd->writesize > 1) { |
| uint64_t __to = to; |
| if (do_div(__to, mtd->writesize) || (total_len % mtd->writesize)) |
| return -EINVAL; |
| } |
| |
| /* make a copy of vecs */ |
| vecs_copy = kmemdup(vecs, sizeof(struct kvec) * count, GFP_KERNEL); |
| if (!vecs_copy) |
| return -ENOMEM; |
| |
| entry_low = 0; |
| for (i = 0; i < concat->num_subdev; i++) { |
| struct mtd_info *subdev = concat->subdev[i]; |
| size_t size, wsize, retsize, old_iov_len; |
| |
| if (to >= subdev->size) { |
| to -= subdev->size; |
| continue; |
| } |
| |
| size = min_t(uint64_t, total_len, subdev->size - to); |
| wsize = size; /* store for future use */ |
| |
| entry_high = entry_low; |
| while (entry_high < count) { |
| if (size <= vecs_copy[entry_high].iov_len) |
| break; |
| size -= vecs_copy[entry_high++].iov_len; |
| } |
| |
| old_iov_len = vecs_copy[entry_high].iov_len; |
| vecs_copy[entry_high].iov_len = size; |
| |
| if (!(subdev->flags & MTD_WRITEABLE)) |
| err = -EROFS; |
| else |
| err = mtd_writev(subdev, &vecs_copy[entry_low], |
| entry_high - entry_low + 1, to, |
| &retsize); |
| |
| vecs_copy[entry_high].iov_len = old_iov_len - size; |
| vecs_copy[entry_high].iov_base += size; |
| |
| entry_low = entry_high; |
| |
| if (err) |
| break; |
| |
| *retlen += retsize; |
| total_len -= wsize; |
| |
| if (total_len == 0) |
| break; |
| |
| err = -EINVAL; |
| to = 0; |
| } |
| |
| kfree(vecs_copy); |
| return err; |
| } |
| |
| static int |
| concat_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops) |
| { |
| struct mtd_concat *concat = CONCAT(mtd); |
| struct mtd_oob_ops devops = *ops; |
| int i, err, ret = 0; |
| |
| ops->retlen = ops->oobretlen = 0; |
| |
| for (i = 0; i < concat->num_subdev; i++) { |
| struct mtd_info *subdev = concat->subdev[i]; |
| |
| if (from >= subdev->size) { |
| from -= subdev->size; |
| continue; |
| } |
| |
| /* partial read ? */ |
| if (from + devops.len > subdev->size) |
| devops.len = subdev->size - from; |
| |
| err = mtd_read_oob(subdev, from, &devops); |
| ops->retlen += devops.retlen; |
| ops->oobretlen += devops.oobretlen; |
| |
| /* Save information about bitflips! */ |
| if (unlikely(err)) { |
| if (mtd_is_eccerr(err)) { |
| mtd->ecc_stats.failed++; |
| ret = err; |
| } else if (mtd_is_bitflip(err)) { |
| mtd->ecc_stats.corrected++; |
| /* Do not overwrite -EBADMSG !! */ |
| if (!ret) |
| ret = err; |
| } else |
| return err; |
| } |
| |
| if (devops.datbuf) { |
| devops.len = ops->len - ops->retlen; |
| if (!devops.len) |
| return ret; |
| devops.datbuf += devops.retlen; |
| } |
| if (devops.oobbuf) { |
| devops.ooblen = ops->ooblen - ops->oobretlen; |
| if (!devops.ooblen) |
| return ret; |
| devops.oobbuf += ops->oobretlen; |
| } |
| |
| from = 0; |
| } |
| return -EINVAL; |
| } |
| |
| static int |
| concat_write_oob(struct mtd_info *mtd, loff_t to, struct mtd_oob_ops *ops) |
| { |
| struct mtd_concat *concat = CONCAT(mtd); |
| struct mtd_oob_ops devops = *ops; |
| int i, err; |
| |
| if (!(mtd->flags & MTD_WRITEABLE)) |
| return -EROFS; |
| |
| ops->retlen = ops->oobretlen = 0; |
| |
| for (i = 0; i < concat->num_subdev; i++) { |
| struct mtd_info *subdev = concat->subdev[i]; |
| |
| if (to >= subdev->size) { |
| to -= subdev->size; |
| continue; |
| } |
| |
| /* partial write ? */ |
| if (to + devops.len > subdev->size) |
| devops.len = subdev->size - to; |
| |
| err = mtd_write_oob(subdev, to, &devops); |
| ops->retlen += devops.oobretlen; |
| if (err) |
| return err; |
| |
| if (devops.datbuf) { |
| devops.len = ops->len - ops->retlen; |
| if (!devops.len) |
| return 0; |
| devops.datbuf += devops.retlen; |
| } |
| if (devops.oobbuf) { |
| devops.ooblen = ops->ooblen - ops->oobretlen; |
| if (!devops.ooblen) |
| return 0; |
| devops.oobbuf += devops.oobretlen; |
| } |
| to = 0; |
| } |
| return -EINVAL; |
| } |
| |
| static void concat_erase_callback(struct erase_info *instr) |
| { |
| wake_up((wait_queue_head_t *) instr->priv); |
| } |
| |
| static int concat_dev_erase(struct mtd_info *mtd, struct erase_info *erase) |
| { |
| int err; |
| wait_queue_head_t waitq; |
| DECLARE_WAITQUEUE(wait, current); |
| |
| /* |
| * This code was stol^H^H^H^Hinspired by mtdchar.c |
| */ |
| init_waitqueue_head(&waitq); |
| |
| erase->mtd = mtd; |
| erase->callback = concat_erase_callback; |
| erase->priv = (unsigned long) &waitq; |
| |
| /* |
| * FIXME: Allow INTERRUPTIBLE. Which means |
| * not having the wait_queue head on the stack. |
| */ |
| err = mtd_erase(mtd, erase); |
| if (!err) { |
| set_current_state(TASK_UNINTERRUPTIBLE); |
| add_wait_queue(&waitq, &wait); |
| if (erase->state != MTD_ERASE_DONE |
| && erase->state != MTD_ERASE_FAILED) |
| schedule(); |
| remove_wait_queue(&waitq, &wait); |
| set_current_state(TASK_RUNNING); |
| |
| err = (erase->state == MTD_ERASE_FAILED) ? -EIO : 0; |
| } |
| return err; |
| } |
| |
| static int concat_erase(struct mtd_info *mtd, struct erase_info *instr) |
| { |
| struct mtd_concat *concat = CONCAT(mtd); |
| struct mtd_info *subdev; |
| int i, err; |
| uint64_t length, offset = 0; |
| struct erase_info *erase; |
| |
| if (!(mtd->flags & MTD_WRITEABLE)) |
| return -EROFS; |
| |
| if (instr->addr > concat->mtd.size) |
| return -EINVAL; |
| |
| if (instr->len + instr->addr > concat->mtd.size) |
| return -EINVAL; |
| |
| /* |
| * Check for proper erase block alignment of the to-be-erased area. |
| * It is easier to do this based on the super device's erase |
| * region info rather than looking at each particular sub-device |
| * in turn. |
| */ |
| if (!concat->mtd.numeraseregions) { |
| /* the easy case: device has uniform erase block size */ |
| if (instr->addr & (concat->mtd.erasesize - 1)) |
| return -EINVAL; |
| if (instr->len & (concat->mtd.erasesize - 1)) |
| return -EINVAL; |
| } else { |
| /* device has variable erase size */ |
| struct mtd_erase_region_info *erase_regions = |
| concat->mtd.eraseregions; |
| |
| /* |
| * Find the erase region where the to-be-erased area begins: |
| */ |
| for (i = 0; i < concat->mtd.numeraseregions && |
| instr->addr >= erase_regions[i].offset; i++) ; |
| --i; |
| |
| /* |
| * Now erase_regions[i] is the region in which the |
| * to-be-erased area begins. Verify that the starting |
| * offset is aligned to this region's erase size: |
| */ |
| if (i < 0 || instr->addr & (erase_regions[i].erasesize - 1)) |
| return -EINVAL; |
| |
| /* |
| * now find the erase region where the to-be-erased area ends: |
| */ |
| for (; i < concat->mtd.numeraseregions && |
| (instr->addr + instr->len) >= erase_regions[i].offset; |
| ++i) ; |
| --i; |
| /* |
| * check if the ending offset is aligned to this region's erase size |
| */ |
| if (i < 0 || ((instr->addr + instr->len) & |
| (erase_regions[i].erasesize - 1))) |
| return -EINVAL; |
| } |
| |
| instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN; |
| |
| /* make a local copy of instr to avoid modifying the caller's struct */ |
| erase = kmalloc(sizeof (struct erase_info), GFP_KERNEL); |
| |
| if (!erase) |
| return -ENOMEM; |
| |
| *erase = *instr; |
| length = instr->len; |
| |
| /* |
| * find the subdevice where the to-be-erased area begins, adjust |
| * starting offset to be relative to the subdevice start |
| */ |
| for (i = 0; i < concat->num_subdev; i++) { |
| subdev = concat->subdev[i]; |
| if (subdev->size <= erase->addr) { |
| erase->addr -= subdev->size; |
| offset += subdev->size; |
| } else { |
| break; |
| } |
| } |
| |
| /* must never happen since size limit has been verified above */ |
| BUG_ON(i >= concat->num_subdev); |
| |
| /* now do the erase: */ |
| err = 0; |
| for (; length > 0; i++) { |
| /* loop for all subdevices affected by this request */ |
| subdev = concat->subdev[i]; /* get current subdevice */ |
| |
| /* limit length to subdevice's size: */ |
| if (erase->addr + length > subdev->size) |
| erase->len = subdev->size - erase->addr; |
| else |
| erase->len = length; |
| |
| if (!(subdev->flags & MTD_WRITEABLE)) { |
| err = -EROFS; |
| break; |
| } |
| length -= erase->len; |
| if ((err = concat_dev_erase(subdev, erase))) { |
| /* sanity check: should never happen since |
| * block alignment has been checked above */ |
| BUG_ON(err == -EINVAL); |
| if (erase->fail_addr != MTD_FAIL_ADDR_UNKNOWN) |
| instr->fail_addr = erase->fail_addr + offset; |
| break; |
| } |
| /* |
| * erase->addr specifies the offset of the area to be |
| * erased *within the current subdevice*. It can be |
| * non-zero only the first time through this loop, i.e. |
| * for the first subdevice where blocks need to be erased. |
| * All the following erases must begin at the start of the |
| * current subdevice, i.e. at offset zero. |
| */ |
| erase->addr = 0; |
| offset += subdev->size; |
| } |
| instr->state = erase->state; |
| kfree(erase); |
| if (err) |
| return err; |
| |
| if (instr->callback) |
| instr->callback(instr); |
| return 0; |
| } |
| |
| static int concat_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len) |
| { |
| struct mtd_concat *concat = CONCAT(mtd); |
| int i, err = -EINVAL; |
| |
| if ((len + ofs) > mtd->size) |
| return -EINVAL; |
| |
| for (i = 0; i < concat->num_subdev; i++) { |
| struct mtd_info *subdev = concat->subdev[i]; |
| uint64_t size; |
| |
| if (ofs >= subdev->size) { |
| size = 0; |
| ofs -= subdev->size; |
| continue; |
| } |
| if (ofs + len > subdev->size) |
| size = subdev->size - ofs; |
| else |
| size = len; |
| |
| err = mtd_lock(subdev, ofs, size); |
| if (err) |
| break; |
| |
| len -= size; |
| if (len == 0) |
| break; |
| |
| err = -EINVAL; |
| ofs = 0; |
| } |
| |
| return err; |
| } |
| |
| static int concat_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len) |
| { |
| struct mtd_concat *concat = CONCAT(mtd); |
| int i, err = 0; |
| |
| if ((len + ofs) > mtd->size) |
| return -EINVAL; |
| |
| for (i = 0; i < concat->num_subdev; i++) { |
| struct mtd_info *subdev = concat->subdev[i]; |
| uint64_t size; |
| |
| if (ofs >= subdev->size) { |
| size = 0; |
| ofs -= subdev->size; |
| continue; |
| } |
| if (ofs + len > subdev->size) |
| size = subdev->size - ofs; |
| else |
| size = len; |
| |
| err = mtd_unlock(subdev, ofs, size); |
| if (err) |
| break; |
| |
| len -= size; |
| if (len == 0) |
| break; |
| |
| err = -EINVAL; |
| ofs = 0; |
| } |
| |
| return err; |
| } |
| |
| static void concat_sync(struct mtd_info *mtd) |
| { |
| struct mtd_concat *concat = CONCAT(mtd); |
| int i; |
| |
| for (i = 0; i < concat->num_subdev; i++) { |
| struct mtd_info *subdev = concat->subdev[i]; |
| mtd_sync(subdev); |
| } |
| } |
| |
| static int concat_suspend(struct mtd_info *mtd) |
| { |
| struct mtd_concat *concat = CONCAT(mtd); |
| int i, rc = 0; |
| |
| for (i = 0; i < concat->num_subdev; i++) { |
| struct mtd_info *subdev = concat->subdev[i]; |
| if ((rc = mtd_suspend(subdev)) < 0) |
| return rc; |
| } |
| return rc; |
| } |
| |
| static void concat_resume(struct mtd_info *mtd) |
| { |
| struct mtd_concat *concat = CONCAT(mtd); |
| int i; |
| |
| for (i = 0; i < concat->num_subdev; i++) { |
| struct mtd_info *subdev = concat->subdev[i]; |
| mtd_resume(subdev); |
| } |
| } |
| |
| static int concat_block_isbad(struct mtd_info *mtd, loff_t ofs) |
| { |
| struct mtd_concat *concat = CONCAT(mtd); |
| int i, res = 0; |
| |
| if (!mtd_can_have_bb(concat->subdev[0])) |
| return res; |
| |
| if (ofs > mtd->size) |
| return -EINVAL; |
| |
| for (i = 0; i < concat->num_subdev; i++) { |
| struct mtd_info *subdev = concat->subdev[i]; |
| |
| if (ofs >= subdev->size) { |
| ofs -= subdev->size; |
| continue; |
| } |
| |
| res = mtd_block_isbad(subdev, ofs); |
| break; |
| } |
| |
| return res; |
| } |
| |
| static int concat_block_markbad(struct mtd_info *mtd, loff_t ofs) |
| { |
| struct mtd_concat *concat = CONCAT(mtd); |
| int i, err = -EINVAL; |
| |
| if (!mtd_can_have_bb(concat->subdev[0])) |
| return 0; |
| |
| if (ofs > mtd->size) |
| return -EINVAL; |
| |
| for (i = 0; i < concat->num_subdev; i++) { |
| struct mtd_info *subdev = concat->subdev[i]; |
| |
| if (ofs >= subdev->size) { |
| ofs -= subdev->size; |
| continue; |
| } |
| |
| err = mtd_block_markbad(subdev, ofs); |
| if (!err) |
| mtd->ecc_stats.badblocks++; |
| break; |
| } |
| |
| return err; |
| } |
| |
| /* |
| * try to support NOMMU mmaps on concatenated devices |
| * - we don't support subdev spanning as we can't guarantee it'll work |
| */ |
| static unsigned long concat_get_unmapped_area(struct mtd_info *mtd, |
| unsigned long len, |
| unsigned long offset, |
| unsigned long flags) |
| { |
| struct mtd_concat *concat = CONCAT(mtd); |
| int i; |
| |
| for (i = 0; i < concat->num_subdev; i++) { |
| struct mtd_info *subdev = concat->subdev[i]; |
| |
| if (offset >= subdev->size) { |
| offset -= subdev->size; |
| continue; |
| } |
| |
| /* we've found the subdev over which the mapping will reside */ |
| if (offset + len > subdev->size) |
| return (unsigned long) -EINVAL; |
| |
| return mtd_get_unmapped_area(subdev, len, offset, flags); |
| } |
| |
| return (unsigned long) -ENOSYS; |
| } |
| |
| /* |
| * This function constructs a virtual MTD device by concatenating |
| * num_devs MTD devices. A pointer to the new device object is |
| * stored to *new_dev upon success. This function does _not_ |
| * register any devices: this is the caller's responsibility. |
| */ |
| struct mtd_info *mtd_concat_create(struct mtd_info *subdev[], /* subdevices to concatenate */ |
| int num_devs, /* number of subdevices */ |
| const char *name) |
| { /* name for the new device */ |
| int i; |
| size_t size; |
| struct mtd_concat *concat; |
| uint32_t max_erasesize, curr_erasesize; |
| int num_erase_region; |
| int max_writebufsize = 0; |
| |
| printk(KERN_NOTICE "Concatenating MTD devices:\n"); |
| for (i = 0; i < num_devs; i++) |
| printk(KERN_NOTICE "(%d): \"%s\"\n", i, subdev[i]->name); |
| printk(KERN_NOTICE "into device \"%s\"\n", name); |
| |
| /* allocate the device structure */ |
| size = SIZEOF_STRUCT_MTD_CONCAT(num_devs); |
| concat = kzalloc(size, GFP_KERNEL); |
| if (!concat) { |
| printk |
| ("memory allocation error while creating concatenated device \"%s\"\n", |
| name); |
| return NULL; |
| } |
| concat->subdev = (struct mtd_info **) (concat + 1); |
| |
| /* |
| * Set up the new "super" device's MTD object structure, check for |
| * incompatibilities between the subdevices. |
| */ |
| concat->mtd.type = subdev[0]->type; |
| concat->mtd.flags = subdev[0]->flags; |
| concat->mtd.size = subdev[0]->size; |
| concat->mtd.erasesize = subdev[0]->erasesize; |
| concat->mtd.writesize = subdev[0]->writesize; |
| |
| for (i = 0; i < num_devs; i++) |
| if (max_writebufsize < subdev[i]->writebufsize) |
| max_writebufsize = subdev[i]->writebufsize; |
| concat->mtd.writebufsize = max_writebufsize; |
| |
| concat->mtd.subpage_sft = subdev[0]->subpage_sft; |
| concat->mtd.oobsize = subdev[0]->oobsize; |
| concat->mtd.oobavail = subdev[0]->oobavail; |
| if (subdev[0]->_writev) |
| concat->mtd._writev = concat_writev; |
| if (subdev[0]->_read_oob) |
| concat->mtd._read_oob = concat_read_oob; |
| if (subdev[0]->_write_oob) |
| concat->mtd._write_oob = concat_write_oob; |
| if (subdev[0]->_block_isbad) |
| concat->mtd._block_isbad = concat_block_isbad; |
| if (subdev[0]->_block_markbad) |
| concat->mtd._block_markbad = concat_block_markbad; |
| |
| concat->mtd.ecc_stats.badblocks = subdev[0]->ecc_stats.badblocks; |
| |
| concat->mtd.backing_dev_info = subdev[0]->backing_dev_info; |
| |
| concat->subdev[0] = subdev[0]; |
| |
| for (i = 1; i < num_devs; i++) { |
| if (concat->mtd.type != subdev[i]->type) { |
| kfree(concat); |
| printk("Incompatible device type on \"%s\"\n", |
| subdev[i]->name); |
| return NULL; |
| } |
| if (concat->mtd.flags != subdev[i]->flags) { |
| /* |
| * Expect all flags except MTD_WRITEABLE to be |
| * equal on all subdevices. |
| */ |
| if ((concat->mtd.flags ^ subdev[i]-> |
| flags) & ~MTD_WRITEABLE) { |
| kfree(concat); |
| printk("Incompatible device flags on \"%s\"\n", |
| subdev[i]->name); |
| return NULL; |
| } else |
| /* if writeable attribute differs, |
| make super device writeable */ |
| concat->mtd.flags |= |
| subdev[i]->flags & MTD_WRITEABLE; |
| } |
| |
| /* only permit direct mapping if the BDIs are all the same |
| * - copy-mapping is still permitted |
| */ |
| if (concat->mtd.backing_dev_info != |
| subdev[i]->backing_dev_info) |
| concat->mtd.backing_dev_info = |
| &default_backing_dev_info; |
| |
| concat->mtd.size += subdev[i]->size; |
| concat->mtd.ecc_stats.badblocks += |
| subdev[i]->ecc_stats.badblocks; |
| if (concat->mtd.writesize != subdev[i]->writesize || |
| concat->mtd.subpage_sft != subdev[i]->subpage_sft || |
| concat->mtd.oobsize != subdev[i]->oobsize || |
| !concat->mtd._read_oob != !subdev[i]->_read_oob || |
| !concat->mtd._write_oob != !subdev[i]->_write_oob) { |
| kfree(concat); |
| printk("Incompatible OOB or ECC data on \"%s\"\n", |
| subdev[i]->name); |
| return NULL; |
| } |
| concat->subdev[i] = subdev[i]; |
| |
| } |
| |
| concat->mtd.ecclayout = subdev[0]->ecclayout; |
| |
| concat->num_subdev = num_devs; |
| concat->mtd.name = name; |
| |
| concat->mtd._erase = concat_erase; |
| concat->mtd._read = concat_read; |
| concat->mtd._write = concat_write; |
| concat->mtd._sync = concat_sync; |
| concat->mtd._lock = concat_lock; |
| concat->mtd._unlock = concat_unlock; |
| concat->mtd._suspend = concat_suspend; |
| concat->mtd._resume = concat_resume; |
| concat->mtd._get_unmapped_area = concat_get_unmapped_area; |
| |
| /* |
| * Combine the erase block size info of the subdevices: |
| * |
| * first, walk the map of the new device and see how |
| * many changes in erase size we have |
| */ |
| max_erasesize = curr_erasesize = subdev[0]->erasesize; |
| num_erase_region = 1; |
| for (i = 0; i < num_devs; i++) { |
| if (subdev[i]->numeraseregions == 0) { |
| /* current subdevice has uniform erase size */ |
| if (subdev[i]->erasesize != curr_erasesize) { |
| /* if it differs from the last subdevice's erase size, count it */ |
| ++num_erase_region; |
| curr_erasesize = subdev[i]->erasesize; |
| if (curr_erasesize > max_erasesize) |
| max_erasesize = curr_erasesize; |
| } |
| } else { |
| /* current subdevice has variable erase size */ |
| int j; |
| for (j = 0; j < subdev[i]->numeraseregions; j++) { |
| |
| /* walk the list of erase regions, count any changes */ |
| if (subdev[i]->eraseregions[j].erasesize != |
| curr_erasesize) { |
| ++num_erase_region; |
| curr_erasesize = |
| subdev[i]->eraseregions[j]. |
| erasesize; |
| if (curr_erasesize > max_erasesize) |
| max_erasesize = curr_erasesize; |
| } |
| } |
| } |
| } |
| |
| if (num_erase_region == 1) { |
| /* |
| * All subdevices have the same uniform erase size. |
| * This is easy: |
| */ |
| concat->mtd.erasesize = curr_erasesize; |
| concat->mtd.numeraseregions = 0; |
| } else { |
| uint64_t tmp64; |
| |
| /* |
| * erase block size varies across the subdevices: allocate |
| * space to store the data describing the variable erase regions |
| */ |
| struct mtd_erase_region_info *erase_region_p; |
| uint64_t begin, position; |
| |
| concat->mtd.erasesize = max_erasesize; |
| concat->mtd.numeraseregions = num_erase_region; |
| concat->mtd.eraseregions = erase_region_p = |
| kmalloc(num_erase_region * |
| sizeof (struct mtd_erase_region_info), GFP_KERNEL); |
| if (!erase_region_p) { |
| kfree(concat); |
| printk |
| ("memory allocation error while creating erase region list" |
| " for device \"%s\"\n", name); |
| return NULL; |
| } |
| |
| /* |
| * walk the map of the new device once more and fill in |
| * in erase region info: |
| */ |
| curr_erasesize = subdev[0]->erasesize; |
| begin = position = 0; |
| for (i = 0; i < num_devs; i++) { |
| if (subdev[i]->numeraseregions == 0) { |
| /* current subdevice has uniform erase size */ |
| if (subdev[i]->erasesize != curr_erasesize) { |
| /* |
| * fill in an mtd_erase_region_info structure for the area |
| * we have walked so far: |
| */ |
| erase_region_p->offset = begin; |
| erase_region_p->erasesize = |
| curr_erasesize; |
| tmp64 = position - begin; |
| do_div(tmp64, curr_erasesize); |
| erase_region_p->numblocks = tmp64; |
| begin = position; |
| |
| curr_erasesize = subdev[i]->erasesize; |
| ++erase_region_p; |
| } |
| position += subdev[i]->size; |
| } else { |
| /* current subdevice has variable erase size */ |
| int j; |
| for (j = 0; j < subdev[i]->numeraseregions; j++) { |
| /* walk the list of erase regions, count any changes */ |
| if (subdev[i]->eraseregions[j]. |
| erasesize != curr_erasesize) { |
| erase_region_p->offset = begin; |
| erase_region_p->erasesize = |
| curr_erasesize; |
| tmp64 = position - begin; |
| do_div(tmp64, curr_erasesize); |
| erase_region_p->numblocks = tmp64; |
| begin = position; |
| |
| curr_erasesize = |
| subdev[i]->eraseregions[j]. |
| erasesize; |
| ++erase_region_p; |
| } |
| position += |
| subdev[i]->eraseregions[j]. |
| numblocks * (uint64_t)curr_erasesize; |
| } |
| } |
| } |
| /* Now write the final entry */ |
| erase_region_p->offset = begin; |
| erase_region_p->erasesize = curr_erasesize; |
| tmp64 = position - begin; |
| do_div(tmp64, curr_erasesize); |
| erase_region_p->numblocks = tmp64; |
| } |
| |
| return &concat->mtd; |
| } |
| |
| /* |
| * This function destroys an MTD object obtained from concat_mtd_devs() |
| */ |
| |
| void mtd_concat_destroy(struct mtd_info *mtd) |
| { |
| struct mtd_concat *concat = CONCAT(mtd); |
| if (concat->mtd.numeraseregions) |
| kfree(concat->mtd.eraseregions); |
| kfree(concat); |
| } |
| |
| EXPORT_SYMBOL(mtd_concat_create); |
| EXPORT_SYMBOL(mtd_concat_destroy); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("Robert Kaiser <rkaiser@sysgo.de>"); |
| MODULE_DESCRIPTION("Generic support for concatenating of MTD devices"); |