diff options
| -rw-r--r-- | drivers/mtd/mtdpart.c | 17 | ||||
| -rw-r--r-- | include/linux/mtd/mtd.h | 9 |
2 files changed, 26 insertions, 0 deletions
diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c index 6174a97d790..c66902df317 100644 --- a/drivers/mtd/mtdpart.c +++ b/drivers/mtd/mtdpart.c @@ -151,6 +151,20 @@ static int part_write (struct mtd_info *mtd, loff_t to, size_t len, len, retlen, buf); } +static int part_panic_write (struct mtd_info *mtd, loff_t to, size_t len, + size_t *retlen, const u_char *buf) +{ + struct mtd_part *part = PART(mtd); + if (!(mtd->flags & MTD_WRITEABLE)) + return -EROFS; + if (to >= mtd->size) + len = 0; + else if (to + len > mtd->size) + len = mtd->size - to; + return part->master->panic_write (part->master, to + part->offset, + len, retlen, buf); +} + static int part_write_oob(struct mtd_info *mtd, loff_t to, struct mtd_oob_ops *ops) { @@ -352,6 +366,9 @@ int add_mtd_partitions(struct mtd_info *master, slave->mtd.read = part_read; slave->mtd.write = part_write; + if (master->panic_write) + slave->mtd.panic_write = part_panic_write; + if(master->point && master->unpoint){ slave->mtd.point = part_point; slave->mtd.unpoint = part_unpoint; diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h index 783fc983417..0a13bb35f04 100644 --- a/include/linux/mtd/mtd.h +++ b/include/linux/mtd/mtd.h @@ -152,6 +152,15 @@ struct mtd_info { int (*read) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf); int (*write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf); + /* In blackbox flight recorder like scenarios we want to make successful + writes in interrupt context. panic_write() is only intended to be + called when its known the kernel is about to panic and we need the + write to succeed. Since the kernel is not going to be running for much + longer, this function can break locks and delay to ensure the write + succeeds (but not sleep). */ + + int (*panic_write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf); + int (*read_oob) (struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops); int (*write_oob) (struct mtd_info *mtd, loff_t to, |