From: Nitin Gupta Date: Mon, 17 May 2010 05:32:42 +0000 (+0530) Subject: swap: Add flag to identify block swap devices X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=b27256439568950f30864ccecaeb6dfb588089d5;p=linux-beck.git swap: Add flag to identify block swap devices Added SWP_BLKDEV flag to distinguish block and regular file backed swap devices. We could also check if a swap is entire block device, rather than a file, by: S_ISBLK(swap_info_struct->swap_file->f_mapping->host->i_mode) but, I think, simply checking this flag is more convenient. Signed-off-by: Nitin Gupta Acked-by: Linus Torvalds Acked-by: Nigel Cunningham Acked-by: Pekka Enberg Reviewed-by: Minchan Kim Signed-off-by: Greg Kroah-Hartman --- diff --git a/include/linux/swap.h b/include/linux/swap.h index 1f59d9340c4d..ec2b7a42b45f 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -146,6 +146,7 @@ enum { SWP_DISCARDING = (1 << 3), /* now discarding a free cluster */ SWP_SOLIDSTATE = (1 << 4), /* blkdev seeks are cheap */ SWP_CONTINUED = (1 << 5), /* swap_map has count continuation */ + SWP_BLKDEV = (1 << 6), /* its a block device */ /* add others here before... */ SWP_SCANNING = (1 << 8), /* refcount in scan_swap_map */ }; diff --git a/mm/swapfile.c b/mm/swapfile.c index 6cd0a8f90dc7..ecb069e213d0 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1884,6 +1884,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) if (error < 0) goto bad_swap; p->bdev = bdev; + p->flags |= SWP_BLKDEV; } else if (S_ISREG(inode->i_mode)) { p->bdev = inode->i_sb->s_bdev; mutex_lock(&inode->i_mutex);