openwrtv4/target/linux/generic/patches-3.1/400-rootfs_split.patch
Jonas Gorski f53128f79b target: linux: mtd: fix MTDREFRESH to an arbitrary high number
To make the ioctl number "stable", use an arbitrary high number to prevent
conflicts with new mtd ioctls that would push MTDREFRESH's number.

Also make mtd use the in-kernel mtd headers.

SVN-Revision: 28893
2011-11-09 21:16:36 +00:00

327 lines
9 KiB
Diff

--- a/drivers/mtd/Kconfig
+++ b/drivers/mtd/Kconfig
@@ -33,6 +33,14 @@ config MTD_TESTS
should normally be compiled as kernel modules. The modules perform
various checks and verifications when loaded.
+config MTD_ROOTFS_ROOT_DEV
+ bool "Automatically set 'rootfs' partition to be root filesystem"
+ default y
+
+config MTD_ROOTFS_SPLIT
+ bool "Automatically split 'rootfs' partition for squashfs"
+ default y
+
config MTD_REDBOOT_PARTS
tristate "RedBoot partition table parsing"
---help---
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -29,6 +29,8 @@
#include <linux/kmod.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
+#include <linux/root_dev.h>
+#include <linux/magic.h>
#include <linux/err.h>
#include "mtdcore.h"
@@ -50,7 +52,7 @@ struct mtd_part {
* the pointer to that structure with this macro.
*/
#define PART(x) ((struct mtd_part *)(x))
-
+#define IS_PART(mtd) (mtd->read == part_read)
/*
* MTD methods which simply translate the effective address and pass through
@@ -637,6 +639,155 @@ int mtd_del_partition(struct mtd_info *m
}
EXPORT_SYMBOL_GPL(mtd_del_partition);
+#ifdef CONFIG_MTD_ROOTFS_SPLIT
+#define ROOTFS_SPLIT_NAME "rootfs_data"
+#define ROOTFS_REMOVED_NAME "<removed>"
+
+struct squashfs_super_block {
+ __le32 s_magic;
+ __le32 pad0[9];
+ __le64 bytes_used;
+};
+
+
+static int split_squashfs(struct mtd_info *master, int offset, int *split_offset)
+{
+ struct squashfs_super_block sb;
+ int len, ret;
+
+ ret = master->read(master, offset, sizeof(sb), &len, (void *) &sb);
+ if (ret || (len != sizeof(sb))) {
+ printk(KERN_ALERT "split_squashfs: error occured while reading "
+ "from \"%s\"\n", master->name);
+ return -EINVAL;
+ }
+
+ if (SQUASHFS_MAGIC != le32_to_cpu(sb.s_magic) ) {
+ printk(KERN_ALERT "split_squashfs: no squashfs found in \"%s\"\n",
+ master->name);
+ *split_offset = 0;
+ return 0;
+ }
+
+ if (le64_to_cpu((sb.bytes_used)) <= 0) {
+ printk(KERN_ALERT "split_squashfs: squashfs is empty in \"%s\"\n",
+ master->name);
+ *split_offset = 0;
+ return 0;
+ }
+
+ len = (u32) le64_to_cpu(sb.bytes_used);
+ len += (offset & 0x000fffff);
+ len += (master->erasesize - 1);
+ len &= ~(master->erasesize - 1);
+ len -= (offset & 0x000fffff);
+ *split_offset = offset + len;
+
+ return 0;
+}
+
+static int split_rootfs_data(struct mtd_info *master, struct mtd_info *rpart, const struct mtd_partition *part)
+{
+ struct mtd_partition *dpart;
+ struct mtd_part *slave = NULL;
+ struct mtd_part *spart;
+ int ret, split_offset = 0;
+
+ spart = PART(rpart);
+ ret = split_squashfs(master, spart->offset, &split_offset);
+ if (ret)
+ return ret;
+
+ if (split_offset <= 0)
+ return 0;
+
+ dpart = kmalloc(sizeof(*part)+sizeof(ROOTFS_SPLIT_NAME)+1, GFP_KERNEL);
+ if (dpart == NULL) {
+ printk(KERN_INFO "split_squashfs: no memory for partition \"%s\"\n",
+ ROOTFS_SPLIT_NAME);
+ return -ENOMEM;
+ }
+
+ memcpy(dpart, part, sizeof(*part));
+ dpart->name = (unsigned char *)&dpart[1];
+ strcpy(dpart->name, ROOTFS_SPLIT_NAME);
+
+ dpart->size = rpart->size - (split_offset - spart->offset);
+ dpart->offset = split_offset;
+
+ if (dpart == NULL)
+ return 1;
+
+ printk(KERN_INFO "mtd: partition \"%s\" created automatically, ofs=%llX, len=%llX \n",
+ ROOTFS_SPLIT_NAME, dpart->offset, dpart->size);
+
+ slave = allocate_partition(master, dpart, 0, split_offset);
+ if (IS_ERR(slave))
+ return PTR_ERR(slave);
+ mutex_lock(&mtd_partitions_mutex);
+ list_add(&slave->list, &mtd_partitions);
+ mutex_unlock(&mtd_partitions_mutex);
+
+ add_mtd_device(&slave->mtd);
+
+ rpart->split = &slave->mtd;
+
+ return 0;
+}
+
+static int refresh_rootfs_split(struct mtd_info *mtd)
+{
+ struct mtd_partition tpart;
+ struct mtd_part *part;
+ char *name;
+ //int index = 0;
+ int offset, size;
+ int ret;
+
+ part = PART(mtd);
+
+ /* check for the new squashfs offset first */
+ ret = split_squashfs(part->master, part->offset, &offset);
+ if (ret)
+ return ret;
+
+ if ((offset > 0) && !mtd->split) {
+ printk(KERN_INFO "%s: creating new split partition for \"%s\"\n", __func__, mtd->name);
+ /* if we don't have a rootfs split partition, create a new one */
+ tpart.name = (char *) mtd->name;
+ tpart.size = mtd->size;
+ tpart.offset = part->offset;
+
+ return split_rootfs_data(part->master, &part->mtd, &tpart);
+ } else if ((offset > 0) && mtd->split) {
+ /* update the offsets of the existing partition */
+ size = mtd->size + part->offset - offset;
+
+ part = PART(mtd->split);
+ part->offset = offset;
+ part->mtd.size = size;
+ printk(KERN_INFO "%s: %s partition \"" ROOTFS_SPLIT_NAME "\", offset: 0x%06x (0x%06x)\n",
+ __func__, (!strcmp(part->mtd.name, ROOTFS_SPLIT_NAME) ? "updating" : "creating"),
+ (u32) part->offset, (u32) part->mtd.size);
+ name = kmalloc(sizeof(ROOTFS_SPLIT_NAME) + 1, GFP_KERNEL);
+ strcpy(name, ROOTFS_SPLIT_NAME);
+ part->mtd.name = name;
+ } else if ((offset <= 0) && mtd->split) {
+ printk(KERN_INFO "%s: removing partition \"%s\"\n", __func__, mtd->split->name);
+
+ /* mark existing partition as removed */
+ part = PART(mtd->split);
+ name = kmalloc(sizeof(ROOTFS_SPLIT_NAME) + 1, GFP_KERNEL);
+ strcpy(name, ROOTFS_REMOVED_NAME);
+ part->mtd.name = name;
+ part->offset = 0;
+ part->mtd.size = 0;
+ }
+
+ return 0;
+}
+#endif /* CONFIG_MTD_ROOTFS_SPLIT */
+
/*
* This function, given a master MTD object and a partition table, creates
* and registers slave MTD objects which are bound to the master according to
@@ -653,6 +804,9 @@ int add_mtd_partitions(struct mtd_info *
struct mtd_part *slave;
uint64_t cur_offset = 0;
int i;
+#ifdef CONFIG_MTD_ROOTFS_SPLIT
+ int ret;
+#endif
printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
@@ -667,12 +821,53 @@ int add_mtd_partitions(struct mtd_info *
add_mtd_device(&slave->mtd);
+ if (!strcmp(parts[i].name, "rootfs")) {
+#ifdef CONFIG_MTD_ROOTFS_ROOT_DEV
+ if (ROOT_DEV == 0) {
+ printk(KERN_NOTICE "mtd: partition \"rootfs\" "
+ "set to be root filesystem\n");
+ ROOT_DEV = MKDEV(MTD_BLOCK_MAJOR, slave->mtd.index);
+ }
+#endif
+#ifdef CONFIG_MTD_ROOTFS_SPLIT
+ ret = split_rootfs_data(master, &slave->mtd, &parts[i]);
+ /* if (ret == 0)
+ * j++; */
+#endif
+ }
+
cur_offset = slave->offset + slave->mtd.size;
}
return 0;
}
+int mtd_device_refresh(struct mtd_info *mtd)
+{
+ int ret = 0;
+
+ if (IS_PART(mtd)) {
+ struct mtd_part *part;
+ struct mtd_info *master;
+
+ part = PART(mtd);
+ master = part->master;
+ if (master->refresh_device)
+ ret = master->refresh_device(master);
+ }
+
+ if (!ret && mtd->refresh_device)
+ ret = mtd->refresh_device(mtd);
+
+#ifdef CONFIG_MTD_ROOTFS_SPLIT
+ if (!ret && IS_PART(mtd) && !strcmp(mtd->name, "rootfs"))
+ refresh_rootfs_split(mtd);
+#endif
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mtd_device_refresh);
+
static DEFINE_SPINLOCK(part_parser_lock);
static LIST_HEAD(part_parsers);
--- a/drivers/mtd/mtdchar.c
+++ b/drivers/mtd/mtdchar.c
@@ -948,6 +948,12 @@ static int mtd_ioctl(struct file *file,
break;
}
+ case MTDREFRESH:
+ {
+ ret = mtd_device_refresh(mtd);
+ break;
+ }
+
default:
ret = -ENOTTY;
}
--- a/include/linux/mtd/mtd.h
+++ b/include/linux/mtd/mtd.h
@@ -125,6 +125,7 @@ struct nand_ecclayout {
struct nand_oobfree oobfree[MTD_MAX_OOBFREE_ENTRIES_LARGE];
};
+struct mtd_info;
struct mtd_info {
u_char type;
uint32_t flags;
@@ -277,6 +278,9 @@ struct mtd_info {
struct device dev;
int usecount;
+ int (*refresh_device)(struct mtd_info *mtd);
+ struct mtd_info *split;
+
/* If the driver is something smart, like UBI, it may need to maintain
* its own reference counting. The below functions are only for driver.
* The driver may register its callbacks. These callbacks are not
@@ -327,6 +331,7 @@ struct mtd_partition;
extern int mtd_device_register(struct mtd_info *master,
const struct mtd_partition *parts,
int nr_parts);
+extern int mtd_device_refresh(struct mtd_info *master);
extern int mtd_device_unregister(struct mtd_info *master);
extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
extern int __get_mtd_device(struct mtd_info *mtd);
--- a/include/linux/mtd/partitions.h
+++ b/include/linux/mtd/partitions.h
@@ -34,12 +34,14 @@
* erasesize aligned (e.g. use MTDPART_OFS_NEXTBLK).
*/
+struct mtd_partition;
struct mtd_partition {
char *name; /* identifier string */
uint64_t size; /* partition size */
uint64_t offset; /* offset within the master MTD space */
uint32_t mask_flags; /* master MTD flags to mask out for this partition */
struct nand_ecclayout *ecclayout; /* out of band layout for this partition (NAND only) */
+ int (*refresh_partition)(struct mtd_info *);
};
#define MTDPART_OFS_NXTBLK (-2)
--- a/include/mtd/mtd-abi.h
+++ b/include/mtd/mtd-abi.h
@@ -127,6 +127,7 @@ struct otp_info {
#define MEMWRITEOOB64 _IOWR('M', 21, struct mtd_oob_buf64)
#define MEMREADOOB64 _IOWR('M', 22, struct mtd_oob_buf64)
#define MEMISLOCKED _IOR('M', 23, struct erase_info_user)
+#define MTDREFRESH _IO('M', 50)
/*
* Obsolete legacy interface. Keep it in order not to break userspace