]> git.sur5r.net Git - u-boot/commitdiff
mtd: Add MTD concat support to concatenate multiple MTD NOR devices
authorStefan Roese <sr@denx.de>
Tue, 12 May 2009 12:29:39 +0000 (14:29 +0200)
committerWolfgang Denk <wd@denx.de>
Fri, 12 Jun 2009 18:45:47 +0000 (20:45 +0200)
This patch adds concatenation support to the U-Boot MTD infrastructure.
By enabling CONFIG_MTD_CONCAT this MTD CFI wrapper will concatenate
all found NOR devices into one single MTD device. This can be used by
e.g by UBI to access a partition that spans over multiple NOR chips.

Signed-off-by: Stefan Roese <sr@denx.de>
drivers/mtd/Makefile
drivers/mtd/cfi_mtd.c
drivers/mtd/mtdconcat.c [new file with mode: 0644]
include/linux/mtd/compat.h
include/linux/mtd/concat.h [new file with mode: 0644]

index ed3f91e2a4eb50a857ec89d9760adf8325406881..19dc02b0c3026766a578761c9b52722e79d1413f 100644 (file)
@@ -26,6 +26,7 @@ include $(TOPDIR)/config.mk
 LIB    := $(obj)libmtd.a
 
 COBJS-$(CONFIG_MTD_PARTITIONS) += mtdcore.o mtdpart.o
+COBJS-$(CONFIG_MTD_CONCAT) += mtdconcat.o
 COBJS-$(CONFIG_HAS_DATAFLASH) += at45.o
 COBJS-$(CONFIG_FLASH_CFI_DRIVER) += cfi_flash.o
 COBJS-$(CONFIG_FLASH_CFI_MTD) += cfi_mtd.o
index 4a76917ac39c35f1f8ad54662ae6b314eb19d2b2..300517e869d09d94b34579a206802d70332f04c6 100644 (file)
 
 #include <common.h>
 #include <flash.h>
+#include <malloc.h>
 
 #include <asm/errno.h>
 #include <linux/mtd/mtd.h>
+#include <linux/mtd/concat.h>
 
 extern flash_info_t flash_info[];
 
 static struct mtd_info cfi_mtd_info[CONFIG_SYS_MAX_FLASH_BANKS];
 static char cfi_mtd_names[CONFIG_SYS_MAX_FLASH_BANKS][16];
+#ifdef CONFIG_MTD_CONCAT
+static char c_mtd_name[16];
+#endif
 
 static int cfi_mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
 {
@@ -145,16 +150,68 @@ static int cfi_mtd_unlock(struct mtd_info *mtd, loff_t ofs, size_t len)
 static int cfi_mtd_set_erasesize(struct mtd_info *mtd, flash_info_t *fi)
 {
        int sect_size = 0;
+       int sect_size_old = 0;
        int sect;
+       int regions = 0;
+       int numblocks = 0;
+       ulong offset = 0;
+       ulong base_addr = fi->start[0];
 
        /*
-        * Select the largest sector size as erasesize (e.g. for UBI)
+        * First detect the number of eraseregions so that we can allocate
+        * the array of eraseregions correctly
         */
        for (sect = 0; sect < fi->sector_count; sect++) {
+               if (sect_size_old != flash_sector_size(fi, sect))
+                       regions++;
+               sect_size_old = flash_sector_size(fi, sect);
+       }
+
+       mtd->eraseregions = malloc(sizeof(struct mtd_erase_region_info) * regions);
+
+       /*
+        * Now detect the largest sector and fill the eraseregions
+        */
+       sect_size_old = 0;
+       regions = 0;
+       for (sect = 0; sect < fi->sector_count; sect++) {
+               if ((sect_size_old != flash_sector_size(fi, sect)) &&
+                   (sect_size_old != 0)) {
+                       mtd->eraseregions[regions].offset = offset - base_addr;
+                       mtd->eraseregions[regions].erasesize = sect_size_old;
+                       mtd->eraseregions[regions].numblocks = numblocks;
+
+                       /* Now start counting the next eraseregions */
+                       numblocks = 0;
+                       regions++;
+               } else {
+                       numblocks++;
+               }
+
+               if (sect_size_old != flash_sector_size(fi, sect))
+                       offset = fi->start[sect];
+
+               /*
+                * Select the largest sector size as erasesize (e.g. for UBI)
+                */
                if (flash_sector_size(fi, sect) > sect_size)
                        sect_size = flash_sector_size(fi, sect);
+
+               sect_size_old = flash_sector_size(fi, sect);
        }
 
+       /*
+        * Set the last region
+        */
+       mtd->eraseregions[regions].offset = offset - base_addr;
+       mtd->eraseregions[regions].erasesize = sect_size_old;
+       mtd->eraseregions[regions].numblocks = numblocks + 1;
+
+       if (regions)
+               mtd->numeraseregions = regions + 1;
+       else
+               mtd->numeraseregions = 0;
+
        mtd->erasesize = sect_size;
 
        return 0;
@@ -165,6 +222,8 @@ int cfi_mtd_init(void)
        struct mtd_info *mtd;
        flash_info_t *fi;
        int error, i;
+       int devices_found = 0;
+       struct mtd_info *mtd_list[CONFIG_SYS_MAX_FLASH_BANKS];
 
        for (i = 0; i < CONFIG_SYS_MAX_FLASH_BANKS; i++) {
                fi = &flash_info[i];
@@ -193,7 +252,25 @@ int cfi_mtd_init(void)
 
                if (add_mtd_device(mtd))
                        return -ENOMEM;
+
+               mtd_list[devices_found++] = mtd;
+       }
+
+#ifdef CONFIG_MTD_CONCAT
+       if (devices_found > 1) {
+               /*
+                * We detected multiple devices. Concatenate them together.
+                */
+               sprintf(c_mtd_name, "nor%d", devices_found);
+               mtd = mtd_concat_create(mtd_list, devices_found, c_mtd_name);
+
+               if (mtd == NULL)
+                       return -ENXIO;
+
+               if (add_mtd_device(mtd))
+                       return -ENOMEM;
        }
+#endif /* CONFIG_MTD_CONCAT */
 
        return 0;
 }
diff --git a/drivers/mtd/mtdconcat.c b/drivers/mtd/mtdconcat.c
new file mode 100644 (file)
index 0000000..fc22701
--- /dev/null
@@ -0,0 +1,807 @@
+/*
+ * MTD device concatenation layer
+ *
+ * (C) 2002 Robert Kaiser <rkaiser@sysgo.de>
+ *
+ * NAND support by Christian Gan <cgan@iders.ca>
+ *
+ * This code is GPL
+ */
+
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/compat.h>
+#include <linux/mtd/concat.h>
+#include <ubi_uboot.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 = subdev->read(subdev, from, size, &retsize, buf);
+
+               /* Save information about bitflips! */
+               if (unlikely(err)) {
+                       if (err == -EBADMSG) {
+                               mtd->ecc_stats.failed++;
+                               ret = err;
+                       } else if (err == -EUCLEAN) {
+                               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 = subdev->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_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 = subdev->read_oob(subdev, from, &devops);
+               ops->retlen += devops.retlen;
+               ops->oobretlen += devops.oobretlen;
+
+               /* Save information about bitflips! */
+               if (unlikely(err)) {
+                       if (err == -EBADMSG) {
+                               mtd->ecc_stats.failed++;
+                               ret = err;
+                       } else if (err == -EUCLEAN) {
+                               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 = 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 = subdev->write_oob(subdev, to, &devops);
+               ops->retlen += devops.retlen;
+               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)
+{
+       /* Nothing to do here in U-Boot */
+}
+
+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 (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 ((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 = subdev->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 = subdev->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];
+               subdev->sync(subdev);
+       }
+}
+
+static int concat_block_isbad(struct mtd_info *mtd, loff_t ofs)
+{
+       struct mtd_concat *concat = CONCAT(mtd);
+       int i, res = 0;
+
+       if (!concat->subdev[0]->block_isbad)
+               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 = subdev->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 (!concat->subdev[0]->block_markbad)
+               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 = subdev->block_markbad(subdev, ofs);
+               if (!err)
+                       mtd->ecc_stats.badblocks++;
+               break;
+       }
+
+       return err;
+}
+
+/*
+ * 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;
+
+       debug("Concatenating MTD devices:\n");
+       for (i = 0; i < num_devs; i++)
+               debug("(%d): \"%s\"\n", i, subdev[i]->name);
+       debug("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
+        * incompatibilites 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;
+       concat->mtd.subpage_sft = subdev[0]->subpage_sft;
+       concat->mtd.oobsize = subdev[0]->oobsize;
+       concat->mtd.oobavail = subdev[0]->oobavail;
+       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->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;
+               }
+
+               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;
+
+       /*
+        * 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;
+}
index 9036b74f86e24045b70829de2f03b2e4083a96cc..f0c8464db5a47b5517f8117f001bb92c0f8338cc 100644 (file)
 
 #define kmalloc(size, flags)   malloc(size)
 #define kzalloc(size, flags)   calloc(size, 1)
-#define vmalloc(size)                  malloc(size)
-#define kfree(ptr)                             free(ptr)
-#define vfree(ptr)                             free(ptr)
+#define vmalloc(size)          malloc(size)
+#define kfree(ptr)             free(ptr)
+#define vfree(ptr)             free(ptr)
 
-#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))
+#define DECLARE_WAITQUEUE(...) do { } while (0)
+#define add_wait_queue(...)    do { } while (0)
+#define remove_wait_queue(...) do { } while (0)
+
+#define KERNEL_VERSION(a,b,c)  (((a) << 16) + ((b) << 8) + (c))
 
 /*
  * ..and if you can't take the strict
diff --git a/include/linux/mtd/concat.h b/include/linux/mtd/concat.h
new file mode 100644 (file)
index 0000000..e80c674
--- /dev/null
@@ -0,0 +1,21 @@
+/*
+ * MTD device concatenation layer definitions
+ *
+ * (C) 2002 Robert Kaiser <rkaiser@sysgo.de>
+ *
+ * This code is GPL
+ */
+
+#ifndef MTD_CONCAT_H
+#define MTD_CONCAT_H
+
+
+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   */
+
+void mtd_concat_destroy(struct mtd_info *mtd);
+
+#endif
+