Why should we need pstore_block? 1. Most embedded intelligent equipment have no persistent ram, which increases costs. We perfer to cheaper solutions, like block devices. In fast, there is already a sample for block device logger in driver MTD (drivers/mtd/mtdoops.c). 2. Do not any equipment have battery, which means that it lost all data on general ram if power failure. Pstore has little to do for these equipments. [PATCH v5] On patch 1: 1. rename pstore/rom to pstore/blk 2. Do not allocate any memory in the write path of panic. So, use local array instead in function romz_recover_dmesg_meta. 3. Add C header file "linux/fs.h" to fix implicit declaration of function 'filp_open','kernel_read'... On patch 3: 1. If panic, do not recover pmsg but flush if it is dirty. 2. Fix erase pmsg failed. On patch 4: 1. Create a document for pstore/blk [PATCH v4] On patch 1: 1. Fix always true condition '(--i >= 0) => (0-u32max >= 0)' in function romz_init_zones by defining variable i to 'int' rahter than 'unsigned int'. 2. To make codes more easily to read, we use macro READ_NEXT_ZONE for return value of romz_dmesg_read if it need to read next zone. Moveover, we assign READ_NEXT_ZONE -1024 rather than 0. 3. Add 'FLUSH_META' to 'enum romz_flush_mode' and rename 'NOT_FLUSH' to 'FLUSH_NONE' 4. Function romz_zone_write work badly with FLUSH_PART mode as badly address and offset to write. On patch 3: NEW SUPPORT psmg for pstore_rom. [PATCH v3] On patch 1: Fix build as module error for undefined 'vfs_read' and 'vfs_write' Both of 'vfs_read' and 'vfs_write' haven't be exproted yet, so we use 'kernel_read' and 'kernel_write' instead. [PATCH v2] On patch 1: Fix build as module error for redefinition of 'romz_unregister' and 'romz_register' [PATCH v1] On patch 1: Core codes of pstore_rom, which works well on allwinner(sunxi) platform. On patch 2: A sample for pstore_rom, using general ram rather than block device. liaoweixiong (4): pstore/blk: new support logger for block devices pstore/blk: add sample for pstore_blk pstore/blk: support pmsg for pstore block Documentation: pstore/blk: create document for pstore_blk Documentation/admin-guide/pstore-block.rst | 226 ++++++ MAINTAINERS | 1 + fs/pstore/Kconfig | 20 + fs/pstore/Makefile | 5 + fs/pstore/blkbuf.c | 46 ++ fs/pstore/blkzone.c | 1168 ++++++++++++++++++++++++++++ include/linux/pstore_blk.h | 62 ++ 7 files changed, 1528 insertions(+) create mode 100644 Documentation/admin-guide/pstore-block.rst create mode 100644 fs/pstore/blkbuf.c create mode 100644 fs/pstore/blkzone.c create mode 100644 include/linux/pstore_blk.h -- 1.9.1
