From 1525fb3bb6d69028b3941d34363397c28345ffab Mon Sep 17 00:00:00 2001 From: WeiXiong Liao Date: Wed, 25 Mar 2020 16:55:04 +0800 Subject: pstore/blk: Provide way to query pstore configuration In order to configure itself, the MTD backend needs to be able to query the current pstore configuration. Introduce pstore_blk_get_config() for this purpose. Signed-off-by: WeiXiong Liao Link: https://lore.kernel.org/lkml/20200511233229.27745-9-keescook@chromium.org/ Co-developed-by: Kees Cook Signed-off-by: Kees Cook --- fs/pstore/blk.c | 37 ++++++++++++++++++++++++++++++------- 1 file changed, 30 insertions(+), 7 deletions(-) (limited to 'fs') diff --git a/fs/pstore/blk.c b/fs/pstore/blk.c index 67343d6aa27a..631bc27c8661 100644 --- a/fs/pstore/blk.c +++ b/fs/pstore/blk.c @@ -94,6 +94,17 @@ struct bdev_info { sector_t start_sect; }; +#define check_size(name, alignsize) ({ \ + long _##name_ = (name); \ + _##name_ = _##name_ <= 0 ? 0 : (_##name_ * 1024); \ + if (_##name_ & ((alignsize) - 1)) { \ + pr_info(#name " must align to %d\n", \ + (alignsize)); \ + _##name_ = ALIGN(name, (alignsize)); \ + } \ + _##name_; \ +}) + /** * struct pstore_device_info - back-end pstore/blk driver structure. * @@ -149,13 +160,11 @@ static int psblk_register_do(struct pstore_device_info *dev) dev->flags = UINT_MAX; #define verify_size(name, alignsize, enabled) { \ - long _##name_ = (enabled) ? (name) : 0; \ - _##name_ = _##name_ <= 0 ? 0 : (_##name_ * 1024); \ - if (_##name_ & ((alignsize) - 1)) { \ - pr_info(#name " must align to %d\n", \ - (alignsize)); \ - _##name_ = ALIGN(name, (alignsize)); \ - } \ + long _##name_; \ + if (enabled) \ + _##name_ = check_size(name, alignsize); \ + else \ + _##name_ = 0; \ name = _##name_ / 1024; \ pstore_zone_info->name = _##name_; \ } @@ -453,6 +462,20 @@ void unregister_pstore_blk(unsigned int major) } EXPORT_SYMBOL_GPL(unregister_pstore_blk); +/* get information of pstore/blk */ +int pstore_blk_get_config(struct pstore_blk_config *info) +{ + strncpy(info->device, blkdev, 80); + info->max_reason = max_reason; + info->kmsg_size = check_size(kmsg_size, 4096); + info->pmsg_size = check_size(pmsg_size, 4096); + info->ftrace_size = check_size(ftrace_size, 4096); + info->console_size = check_size(console_size, 4096); + + return 0; +} +EXPORT_SYMBOL_GPL(pstore_blk_get_config); + static void __exit pstore_blk_exit(void) { mutex_lock(&pstore_blk_lock); -- cgit v1.2.3