From 2af3a8159cd204fc8437ed2f75863f0fb930f0d0 Mon Sep 17 00:00:00 2001 From: Toshi Kani Date: Tue, 10 May 2016 10:23:52 -0600 Subject: [PATCH] block: Add vfs_msg() interface In preparation of moving DAX capability checks to the block layer from filesystem code, add a VFS message interface that aligns with filesystem's message format. For instance, a vfs_msg() message followed by XFS messages in case of a dax mount error may look like: VFS (pmem0p1): error: unaligned partition for dax XFS (pmem0p1): DAX unsupported by block device. Turning off DAX. XFS (pmem0p1): Mounting V5 Filesystem : vfs_msg() is largely based on ext4_msg(). Signed-off-by: Toshi Kani Reviewed-by: Christoph Hellwig Cc: Alexander Viro Cc: Jens Axboe Cc: "Theodore Ts'o" Cc: Andreas Dilger Cc: Jan Kara Cc: Dave Chinner Cc: Dan Williams Cc: Ross Zwisler Cc: Christoph Hellwig Cc: Boaz Harrosh Signed-off-by: Vishal Verma --- fs/block_dev.c | 12 ++++++++++++ include/linux/blkdev.h | 11 +++++++++++ 2 files changed, 23 insertions(+) diff --git a/fs/block_dev.c b/fs/block_dev.c index b25bb230b28a..91e0ec0233c0 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -50,6 +50,18 @@ struct block_device *I_BDEV(struct inode *inode) } EXPORT_SYMBOL(I_BDEV); +void __vfs_msg(struct super_block *sb, const char *prefix, const char *fmt, ...) +{ + struct va_format vaf; + va_list args; + + va_start(args, fmt); + vaf.fmt = fmt; + vaf.va = &args; + printk_ratelimited("%sVFS (%s): %pV\n", prefix, sb->s_id, &vaf); + va_end(args); +} + static void bdev_write_inode(struct block_device *bdev) { struct inode *inode = bdev->bd_inode; diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 669e419d6234..78c48ab22f46 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -767,6 +767,17 @@ static inline void rq_flush_dcache_pages(struct request *rq) } #endif +#ifdef CONFIG_PRINTK +#define vfs_msg(sb, level, fmt, ...) \ + __vfs_msg(sb, level, fmt, ##__VA_ARGS__) +#else +#define vfs_msg(sb, level, fmt, ...) \ +do { \ + no_printk(fmt, ##__VA_ARGS__); \ + __vfs_msg(sb, "", " "); \ +} while (0) +#endif + extern int blk_register_queue(struct gendisk *disk); extern void blk_unregister_queue(struct gendisk *disk); extern blk_qc_t generic_make_request(struct bio *bio);