linux/drivers/block/brd.c, branch v3.4-rc2

block: remove the second argument of k[un]map_atomic()

2012-03-20T13:48:16Z

Signed-off-by: Cong Wang

fs: move code out of buffer.c

2012-01-04T03:54:07Z

Move invalidate_bdev, block_sync_page into fs/block_dev.c. Export kill_bdev as well, so brd doesn't have to open code it. Reduce buffer_head.h requirement accordingly. Removed a rather large comment from invalidate_bdev, as it looked a bit obsolete to bother moving. The small comment replacing it says enough. Signed-off-by: Nick Piggin Cc: Al Viro Cc: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Al Viro

block: remove support for bio remapping from ->make_request

2011-09-12T10:12:01Z

There is very little benefit in allowing to let a ->make_request instance update the bios device and sector and loop around it in __generic_make_request when we can archive the same through calling generic_make_request from the driver and letting the loop in generic_make_request handle it. Note that various drivers got the return value from ->make_request and returned non-zero values for errors. Signed-off-by: Christoph Hellwig Acked-by: NeilBrown Signed-off-by: Jens Axboe

brd: export module parameters

2011-05-26T19:06:50Z

Export 'rd_nr', 'rd_size' and 'max_part' parameters to sysfs so user can know that how many devices are allowed, how big each device is and how many partitions are supported. If 'max_part' is 0, it means simply the device doesn't support partitioning. Also note that 'max_part' can be adjusted to power of 2 minus 1 form if needed. User should check this value after the module loading if he/she want to use that number correctly (i.e. fdisk, mknod, etc.). Signed-off-by: Namhyung Kim Cc: Laurent Vivier Signed-off-by: Jens Axboe

brd: fix comment on initial device creation

2011-05-26T19:06:50Z

If 'rd_nr' param was not specified, 16 (can be adjusted via CONFIG_BLK_DEV_RAM_COUNT) devices would be created by default but comment said 1. Fix it. Signed-off-by: Namhyung Kim Signed-off-by: Jens Axboe

brd: handle on-demand devices correctly

2011-05-26T19:06:50Z

When finding or allocating a ram disk device, brd_probe() did not take partition numbers into account so that it can result to a different device. Consider following example (I set CONFIG_BLK_DEV_RAM_COUNT=4 for simplicity) : $ sudo modprobe brd max_part=15 $ ls -l /dev/ram* brw-rw---- 1 root disk 1, 0 2011-05-25 15:41 /dev/ram0 brw-rw---- 1 root disk 1, 16 2011-05-25 15:41 /dev/ram1 brw-rw---- 1 root disk 1, 32 2011-05-25 15:41 /dev/ram2 brw-rw---- 1 root disk 1, 48 2011-05-25 15:41 /dev/ram3 $ sudo mknod /dev/ram4 b 1 64 $ sudo dd if=/dev/zero of=/dev/ram4 bs=4k count=256 256+0 records in 256+0 records out 1048576 bytes (1.0 MB) copied, 0.00215578 s, 486 MB/s namhyung@leonhard:linux$ ls -l /dev/ram* brw-rw---- 1 root disk 1, 0 2011-05-25 15:41 /dev/ram0 brw-rw---- 1 root disk 1, 16 2011-05-25 15:41 /dev/ram1 brw-rw---- 1 root disk 1, 32 2011-05-25 15:41 /dev/ram2 brw-rw---- 1 root disk 1, 48 2011-05-25 15:41 /dev/ram3 brw-r--r-- 1 root root 1, 64 2011-05-25 15:45 /dev/ram4 brw-rw---- 1 root disk 1, 1024 2011-05-25 15:44 /dev/ram64 After this patch, /dev/ram4 - instead of /dev/ram64 - was accessed correctly. In addition, 'range' passed to blk_register_region() should include all range of dev_t that RAMDISK_MAJOR can address. It does not need to be limited by partition numbers unless 'rd_nr' param was specified. Signed-off-by: Namhyung Kim Cc: Laurent Vivier Cc: stable@kernel.org Signed-off-by: Jens Axboe

brd: limit 'max_part' module param to DISK_MAX_PARTS

2011-05-26T19:06:50Z

The 'max_part' parameter controls the number of maximum partition a brd device can have. However if a user specifies very large value it would exceed the limitation of device minor number and can cause a kernel panic (or, at least, produce invalid device nodes in some cases). On my desktop system, following command kills the kernel. On qemu, it triggers similar oops but the kernel was alive: $ sudo modprobe brd max_part=100000 BUG: unable to handle kernel NULL pointer dereference at 0000000000000058 IP: [] sysfs_create_dir+0x2d/0xae PGD 7af1067 PUD 7b19067 PMD 0 Oops: 0000 [#1] SMP last sysfs file: CPU 0 Modules linked in: brd(+) Pid: 44, comm: insmod Tainted: G W 2.6.39-qemu+ #158 Bochs Bochs RIP: 0010:[] [] sysfs_create_dir+0x2d/0xae RSP: 0018:ffff880007b15d78 EFLAGS: 00000286 RAX: ffff880007b05478 RBX: ffff880007a52760 RCX: ffff880007b15dc8 RDX: ffff880007a4f900 RSI: ffff880007b15e48 RDI: ffff880007a52760 RBP: ffff880007b15da8 R08: 0000000000000002 R09: 0000000000000000 R10: ffff880007b15e48 R11: ffff880007b05478 R12: 0000000000000000 R13: ffff880007b05478 R14: 0000000000400920 R15: 0000000000000063 FS: 0000000002160880(0063) GS:ffff880007c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000058 CR3: 0000000007b1c000 CR4: 00000000000006b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 0000000000000000 DR7: 0000000000000000 Process insmod (pid: 44, threadinfo ffff880007b14000, task ffff880007acb980) Stack: ffff880007b15dc8 ffff880007b05478 ffff880007b15da8 00000000fffffffe ffff880007a52760 ffff880007b05478 ffff880007b15de8 ffffffff81143c0a 0000000000400920 ffff880007a52760 ffff880007b05478 0000000000000000 Call Trace: [] kobject_add_internal+0xdf/0x1a0 [] kobject_add_varg+0x41/0x50 [] kobject_add+0x64/0x66 [] blk_register_queue+0x5f/0xb8 [] add_disk+0xdf/0x289 [] brd_init+0xdf/0x1aa [brd] [] ? 0xffffffffa0003fff [] ? 0xffffffffa0003fff [] do_one_initcall+0x7a/0x12e [] sys_init_module+0x9c/0x1dc [] system_call_fastpath+0x16/0x1b Code: 89 e5 41 55 41 54 53 48 89 fb 48 83 ec 18 48 85 ff 75 04 0f 0b eb fe 48 8b 47 18 49 c7 c4 70 1e 4d 81 48 85 c0 74 04 4c 8b 60 30 8b 44 24 58 45 31 ed 0f b6 c4 85 c0 74 0d 48 8b 43 28 48 89 RIP [] sysfs_create_dir+0x2d/0xae RSP CR2: 0000000000000058 ---[ end trace aebb1175ce1f6739 ]--- Signed-off-by: Namhyung Kim Cc: Laurent Vivier Cc: stable@kernel.org Signed-off-by: Jens Axboe

brd: get rid of unused members from struct brd_device

2011-05-26T19:06:50Z

brd_refcnt, brd_offset, brd_sizelimit and brd_blocksize in struct brd_device seem to be copied from struct loop_device but they're not used anywhere. Let get rid of them. Signed-off-by: Namhyung Kim Signed-off-by: Jens Axboe

Merge branch 'for-2.6.37/barrier' of git://git.kernel.dk/linux-2.6-block

2010-10-23T00:07:18Z

* 'for-2.6.37/barrier' of git://git.kernel.dk/linux-2.6-block: (46 commits) xen-blkfront: disable barrier/flush write support Added blk-lib.c and blk-barrier.c was renamed to blk-flush.c block: remove BLKDEV_IFL_WAIT aic7xxx_old: removed unused 'req' variable block: remove the BH_Eopnotsupp flag block: remove the BLKDEV_IFL_BARRIER flag block: remove the WRITE_BARRIER flag swap: do not send discards as barriers fat: do not send discards as barriers ext4: do not send discards as barriers jbd2: replace barriers with explicit flush / FUA usage jbd2: Modify ASYNC_COMMIT code to not rely on queue draining on barrier jbd: replace barriers with explicit flush / FUA usage nilfs2: replace barriers with explicit flush / FUA usage reiserfs: replace barriers with explicit flush / FUA usage gfs2: replace barriers with explicit flush / FUA usage btrfs: replace barriers with explicit flush / FUA usage xfs: replace barriers with explicit flush / FUA usage block: pass gfp_mask and flags to sb_issue_discard dm: convey that all flushes are processed as empty ...

block: autoconvert trivial BKL users to private mutex

2010-10-05T13:01:10Z

The block device drivers have all gained new lock_kernel calls from a recent pushdown, and some of the drivers were already using the BKL before. This turns the BKL into a set of per-driver mutexes. Still need to check whether this is safe to do. file=$1 name=$2 if grep -q lock_kernel ${file} ; then if grep -q 'include.*linux.mutex.h' ${file} ; then sed -i '/include.*/d' ${file} else sed -i 's/include.*.*$/include /g' ${file} fi sed -i ${file} \ -e "/^#include.*linux.mutex.h/,$ { 1,/^$static\|int\|long$/ { /^$static\|int\|long$/istatic DEFINE_MUTEX(${name}_mutex); } }" \ -e "s/$un$*lock_kernel\>[ ]*()/mutex_\1lock(\&${name}_mutex)/g" \ -e '/[ ]*cycle_kernel_lock();/d' else sed -i -e '/include.*\/d' ${file} \ -e '/cycle_kernel_lock()/d' fi Signed-off-by: Arnd Bergmann