From 87a8e8ac1067f58ba831c4aae443f3655c31cd80 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Mon, 21 Sep 2009 09:58:36 +0000 Subject: [PATCH] implement write support for partitions covering only a part of an eraseblock (buffer data that would otherwise be erased) SVN-Revision: 17658 --- target/linux/generic-2.6/config-2.6.30 | 2 +- target/linux/generic-2.6/config-2.6.31 | 2 +- .../222-partial_eraseblock_write.patch | 146 ++++++++++++++++++ .../222-partial_eraseblock_write.patch | 146 ++++++++++++++++++ 4 files changed, 294 insertions(+), 2 deletions(-) create mode 100644 target/linux/generic-2.6/patches-2.6.30/222-partial_eraseblock_write.patch create mode 100644 target/linux/generic-2.6/patches-2.6.31/222-partial_eraseblock_write.patch diff --git a/target/linux/generic-2.6/config-2.6.30 b/target/linux/generic-2.6/config-2.6.30 index 9202ffe993..bdd84cd9e4 100644 --- a/target/linux/generic-2.6/config-2.6.30 +++ b/target/linux/generic-2.6/config-2.6.30 @@ -1100,7 +1100,7 @@ CONFIG_MTD_PARTITIONS=y # CONFIG_MTD_RAM is not set CONFIG_MTD_REDBOOT_DIRECTORY_BLOCK=-1 # CONFIG_MTD_REDBOOT_PARTS is not set -CONFIG_MTD_REDBOOT_PARTS_READONLY=y +# CONFIG_MTD_REDBOOT_PARTS_READONLY is not set # CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED is not set # CONFIG_MTD_ROM is not set CONFIG_MTD_ROOTFS_ROOT_DEV=y diff --git a/target/linux/generic-2.6/config-2.6.31 b/target/linux/generic-2.6/config-2.6.31 index a784be9481..a90d5f5665 100644 --- a/target/linux/generic-2.6/config-2.6.31 +++ b/target/linux/generic-2.6/config-2.6.31 @@ -1112,7 +1112,7 @@ CONFIG_MTD_PARTITIONS=y # CONFIG_MTD_RAM is not set CONFIG_MTD_REDBOOT_DIRECTORY_BLOCK=-1 # CONFIG_MTD_REDBOOT_PARTS is not set -CONFIG_MTD_REDBOOT_PARTS_READONLY=y +# CONFIG_MTD_REDBOOT_PARTS_READONLY is not set # CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED is not set # CONFIG_MTD_ROM is not set CONFIG_MTD_ROOTFS_ROOT_DEV=y diff --git a/target/linux/generic-2.6/patches-2.6.30/222-partial_eraseblock_write.patch b/target/linux/generic-2.6/patches-2.6.30/222-partial_eraseblock_write.patch new file mode 100644 index 0000000000..dfabeaa9ad --- /dev/null +++ b/target/linux/generic-2.6/patches-2.6.30/222-partial_eraseblock_write.patch @@ -0,0 +1,146 @@ +--- a/drivers/mtd/mtdpart.c ++++ b/drivers/mtd/mtdpart.c +@@ -21,6 +21,8 @@ + #include + #include + ++#define MTD_ERASE_PARTIAL 0x8000 /* partition only covers parts of an erase block */ ++ + /* Our partition linked list */ + static LIST_HEAD(mtd_partitions); + +@@ -228,13 +230,60 @@ static int part_erase(struct mtd_info *m + return -EROFS; + if (instr->addr >= mtd->size) + return -EINVAL; ++ ++ instr->partial_start = false; ++ if (mtd->flags & MTD_ERASE_PARTIAL) { ++ size_t readlen = 0; ++ u64 mtd_ofs; ++ ++ instr->erase_buf = kmalloc(part->master->erasesize, GFP_ATOMIC); ++ if (!instr->erase_buf) ++ return -ENOMEM; ++ ++ mtd_ofs = part->offset + instr->addr; ++ instr->erase_buf_ofs = do_div(mtd_ofs, part->master->erasesize); ++ ++ if (instr->erase_buf_ofs > 0) { ++ instr->addr -= instr->erase_buf_ofs; ++ ret = part->master->read(part->master, ++ instr->addr + part->offset, ++ part->master->erasesize, ++ &readlen, instr->erase_buf); ++ ++ instr->partial_start = true; ++ } else { ++ mtd_ofs = part->offset + part->mtd.size; ++ instr->erase_buf_ofs = part->master->erasesize - ++ do_div(mtd_ofs, part->master->erasesize); ++ ++ if (instr->erase_buf_ofs > 0) { ++ instr->len += instr->erase_buf_ofs; ++ ret = part->master->read(part->master, ++ part->offset + instr->addr + ++ instr->len - part->master->erasesize, ++ part->master->erasesize, &readlen, ++ instr->erase_buf); ++ } else { ++ ret = 0; ++ } ++ } ++ if (ret < 0) { ++ kfree(instr->erase_buf); ++ return ret; ++ } ++ ++ } ++ + instr->addr += part->offset; + ret = part->master->erase(part->master, instr); + if (ret) { + if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN) + instr->fail_addr -= part->offset; + instr->addr -= part->offset; ++ if (mtd->flags & MTD_ERASE_PARTIAL) ++ kfree(instr->erase_buf); + } ++ + return ret; + } + +@@ -242,7 +291,25 @@ void mtd_erase_callback(struct erase_inf + { + if (instr->mtd->erase == part_erase) { + struct mtd_part *part = PART(instr->mtd); ++ size_t wrlen = 0; + ++ if (instr->mtd->flags & MTD_ERASE_PARTIAL) { ++ if (instr->partial_start) { ++ part->master->write(part->master, ++ instr->addr, instr->erase_buf_ofs, ++ &wrlen, instr->erase_buf); ++ instr->addr += instr->erase_buf_ofs; ++ } else { ++ instr->len -= instr->erase_buf_ofs; ++ part->master->write(part->master, ++ instr->addr + instr->len, ++ instr->erase_buf_ofs, &wrlen, ++ instr->erase_buf + ++ part->master->erasesize - ++ instr->erase_buf_ofs); ++ } ++ kfree(instr->erase_buf); ++ } + if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN) + instr->fail_addr -= part->offset; + instr->addr -= part->offset; +@@ -476,18 +543,24 @@ static struct mtd_part *add_one_partitio + if ((slave->mtd.flags & MTD_WRITEABLE) && + mtd_mod_by_eb(slave->offset, &slave->mtd)) { + /* Doesn't start on a boundary of major erase size */ +- /* FIXME: Let it be writable if it is on a boundary of +- * _minor_ erase size though */ +- slave->mtd.flags &= ~MTD_WRITEABLE; +- printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n", +- part->name); ++ slave->mtd.flags |= MTD_ERASE_PARTIAL; ++ if (((u32) slave->mtd.size) > master->erasesize) ++ slave->mtd.flags &= ~MTD_WRITEABLE; ++ else ++ slave->mtd.erasesize = slave->mtd.size; + } + if ((slave->mtd.flags & MTD_WRITEABLE) && +- mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) { +- slave->mtd.flags &= ~MTD_WRITEABLE; +- printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n", +- part->name); +- } ++ mtd_mod_by_eb(slave->offset + slave->mtd.size, &slave->mtd)) { ++ slave->mtd.flags |= MTD_ERASE_PARTIAL; ++ ++ if ((u32) slave->mtd.size > master->erasesize) ++ slave->mtd.flags &= ~MTD_WRITEABLE; ++ else ++ slave->mtd.erasesize = slave->mtd.size; ++ } ++ if ((slave->mtd.flags & (MTD_ERASE_PARTIAL|MTD_WRITEABLE)) == MTD_ERASE_PARTIAL) ++ printk(KERN_WARNING"mtd: partition \"%s\" must either start or end on erase block boundary or be smaller than an erase block -- forcing read-only\n", ++ part->name); + + slave->mtd.ecclayout = master->ecclayout; + if (master->block_isbad) { +--- a/include/linux/mtd/mtd.h ++++ b/include/linux/mtd/mtd.h +@@ -46,6 +46,10 @@ struct erase_info { + u_long priv; + u_char state; + struct erase_info *next; ++ ++ u8 *erase_buf; ++ u32 erase_buf_ofs; ++ bool partial_start; + }; + + struct mtd_erase_region_info { diff --git a/target/linux/generic-2.6/patches-2.6.31/222-partial_eraseblock_write.patch b/target/linux/generic-2.6/patches-2.6.31/222-partial_eraseblock_write.patch new file mode 100644 index 0000000000..d3234f004b --- /dev/null +++ b/target/linux/generic-2.6/patches-2.6.31/222-partial_eraseblock_write.patch @@ -0,0 +1,146 @@ +--- a/drivers/mtd/mtdpart.c ++++ b/drivers/mtd/mtdpart.c +@@ -21,6 +21,8 @@ + #include + #include + ++#define MTD_ERASE_PARTIAL 0x8000 /* partition only covers parts of an erase block */ ++ + /* Our partition linked list */ + static LIST_HEAD(mtd_partitions); + +@@ -226,13 +228,60 @@ static int part_erase(struct mtd_info *m + return -EROFS; + if (instr->addr >= mtd->size) + return -EINVAL; ++ ++ instr->partial_start = false; ++ if (mtd->flags & MTD_ERASE_PARTIAL) { ++ size_t readlen = 0; ++ u64 mtd_ofs; ++ ++ instr->erase_buf = kmalloc(part->master->erasesize, GFP_ATOMIC); ++ if (!instr->erase_buf) ++ return -ENOMEM; ++ ++ mtd_ofs = part->offset + instr->addr; ++ instr->erase_buf_ofs = do_div(mtd_ofs, part->master->erasesize); ++ ++ if (instr->erase_buf_ofs > 0) { ++ instr->addr -= instr->erase_buf_ofs; ++ ret = part->master->read(part->master, ++ instr->addr + part->offset, ++ part->master->erasesize, ++ &readlen, instr->erase_buf); ++ ++ instr->partial_start = true; ++ } else { ++ mtd_ofs = part->offset + part->mtd.size; ++ instr->erase_buf_ofs = part->master->erasesize - ++ do_div(mtd_ofs, part->master->erasesize); ++ ++ if (instr->erase_buf_ofs > 0) { ++ instr->len += instr->erase_buf_ofs; ++ ret = part->master->read(part->master, ++ part->offset + instr->addr + ++ instr->len - part->master->erasesize, ++ part->master->erasesize, &readlen, ++ instr->erase_buf); ++ } else { ++ ret = 0; ++ } ++ } ++ if (ret < 0) { ++ kfree(instr->erase_buf); ++ return ret; ++ } ++ ++ } ++ + instr->addr += part->offset; + ret = part->master->erase(part->master, instr); + if (ret) { + if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN) + instr->fail_addr -= part->offset; + instr->addr -= part->offset; ++ if (mtd->flags & MTD_ERASE_PARTIAL) ++ kfree(instr->erase_buf); + } ++ + return ret; + } + +@@ -240,7 +289,25 @@ void mtd_erase_callback(struct erase_inf + { + if (instr->mtd->erase == part_erase) { + struct mtd_part *part = PART(instr->mtd); ++ size_t wrlen = 0; + ++ if (instr->mtd->flags & MTD_ERASE_PARTIAL) { ++ if (instr->partial_start) { ++ part->master->write(part->master, ++ instr->addr, instr->erase_buf_ofs, ++ &wrlen, instr->erase_buf); ++ instr->addr += instr->erase_buf_ofs; ++ } else { ++ instr->len -= instr->erase_buf_ofs; ++ part->master->write(part->master, ++ instr->addr + instr->len, ++ instr->erase_buf_ofs, &wrlen, ++ instr->erase_buf + ++ part->master->erasesize - ++ instr->erase_buf_ofs); ++ } ++ kfree(instr->erase_buf); ++ } + if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN) + instr->fail_addr -= part->offset; + instr->addr -= part->offset; +@@ -472,18 +539,24 @@ static struct mtd_part *add_one_partitio + if ((slave->mtd.flags & MTD_WRITEABLE) && + mtd_mod_by_eb(slave->offset, &slave->mtd)) { + /* Doesn't start on a boundary of major erase size */ +- /* FIXME: Let it be writable if it is on a boundary of +- * _minor_ erase size though */ +- slave->mtd.flags &= ~MTD_WRITEABLE; +- printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n", +- part->name); ++ slave->mtd.flags |= MTD_ERASE_PARTIAL; ++ if (((u32) slave->mtd.size) > master->erasesize) ++ slave->mtd.flags &= ~MTD_WRITEABLE; ++ else ++ slave->mtd.erasesize = slave->mtd.size; + } + if ((slave->mtd.flags & MTD_WRITEABLE) && +- mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) { +- slave->mtd.flags &= ~MTD_WRITEABLE; +- printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n", +- part->name); +- } ++ mtd_mod_by_eb(slave->offset + slave->mtd.size, &slave->mtd)) { ++ slave->mtd.flags |= MTD_ERASE_PARTIAL; ++ ++ if ((u32) slave->mtd.size > master->erasesize) ++ slave->mtd.flags &= ~MTD_WRITEABLE; ++ else ++ slave->mtd.erasesize = slave->mtd.size; ++ } ++ if ((slave->mtd.flags & (MTD_ERASE_PARTIAL|MTD_WRITEABLE)) == MTD_ERASE_PARTIAL) ++ printk(KERN_WARNING"mtd: partition \"%s\" must either start or end on erase block boundary or be smaller than an erase block -- forcing read-only\n", ++ part->name); + + slave->mtd.ecclayout = master->ecclayout; + if (master->block_isbad) { +--- a/include/linux/mtd/mtd.h ++++ b/include/linux/mtd/mtd.h +@@ -46,6 +46,10 @@ struct erase_info { + u_long priv; + u_char state; + struct erase_info *next; ++ ++ u8 *erase_buf; ++ u32 erase_buf_ofs; ++ bool partial_start; + }; + + struct mtd_erase_region_info { -- 2.25.1