| Age | Commit message (Collapse) | Author | Files | Lines |
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Since this is relating to FS_XIP, not KERNEL_XIP, it should be called
DAX instead of XIP.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Andreas Dilger <andreas.dilger@intel.com>
Cc: Boaz Harrosh <boaz@plexistor.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Because of the direct_access() API which returns a PFN. partitions
better start on 4K boundary, else offset ZERO of a partition will
not be aligned and blk_direct_access() will fail the call.
By setting blk_queue_physical_block_size(PAGE_SIZE) we can communicate
this to fdisk and friends.
The call to blk_queue_physical_block_size() is harmless and will
not affect the Kernel behavior in any way. It is only for
communication to user-mode.
before this patch running fdisk on a default size brd of 4M
the first sector offered is 34 (BAD), but after this patch it
will be 40, ie 8 sectors aligned. Also when entering some random
partition sizes the next partition-start sector is offered 8 sectors
aligned after this patch. (Please note that with fdisk the user
can still enter bad values, only the offered default values will
be correct)
Note that with bdev-size > 4M fdisk will try to align on a 1M
boundary (above first-sector will be 2048), in any case.
CC: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Boaz Harrosh <boaz@plexistor.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
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This patch fixes up brd's partitions scheme, now enjoying all worlds.
The MAIN fix here is that currently, if one fdisks some partitions,
a BAD bug will make all partitions point to the same start-end sector
ie: 0 - brd_size And an mkfs of any partition would trash the partition
table and the other partition.
Another fix is that "mount -U uuid" will not work if show_part was not
specified, because of the GENHD_FL_SUPPRESS_PARTITION_INFO flag.
We now always load without it and remove the show_part parameter.
[We remove Dmitry's new module-param part_show it is now always
show]
So NOW the logic goes like this:
* max_part - Just says how many minors to reserve between ramX
devices. In any way, there can be as many partition as requested.
If minors between devices ends, then dynamic 259-major ids will
be allocated on the fly.
The default is now max_part=1, which means all partitions devt(s)
will be from the dynamic (259) major-range.
(If persistent partition minors is needed use max_part=X)
For example with /dev/sdX max_part is hard coded 16.
* Creation of new devices on the fly still/always work:
mknod /path/devnod b 1 X
fdisk -l /path/devnod
Will create a new device if [X / max_part] was not already
created before. (Just as before)
partitions on the dynamically created device will work as well
Same logic applies with minors as with the pre-created ones.
TODO: dynamic grow of device size. So each device can have it's
own size.
CC: Dmitry Monakhov <dmonakhov@openvz.org>
Tested-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Boaz Harrosh <boaz@plexistor.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
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In order to support accesses to larger chunks of memory, pass in a
'size' parameter (counted in bytes), and return the amount available at
that address.
Add a new helper function, bdev_direct_access(), to handle common
functionality including partition handling, checking the length requested
is positive, checking for the sector being page-aligned, and checking
the length of the request does not pass the end of the partition.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Boaz Harrosh <boaz@plexistor.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
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Currenly ram disk is not visiable inside /proc/partitions. This was
done for compatibility reasons here: 53978d0a7a27. But some utilities
expect disk presents in /proc/partitions.
Let's add module's option and let's administrator chose visibility behaviour.
By default, old behaviour preserved.
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
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brd is effectively a thinly provisioned device. Thinly provisioned
devices return -ENOSPC when they can't write a new block. -ENOMEM is an
implementation detail that callers shouldn't know.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Acked-by: Dave Chinner <david@fromorbit.com>
Cc: Dheeraj Reddy <dheeraj.reddy@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dheeraj Reddy <dheeraj.reddy@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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More prep work for immutable biovecs - with immutable bvecs drivers
won't be able to use the biovec directly, they'll need to use helpers
that take into account bio->bi_iter.bi_bvec_done.
This updates callers for the new usage without changing the
implementation yet.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Ed L. Cashin" <ecashin@coraid.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Cc: Jim Paris <jim@jtan.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Yehuda Sadeh <yehuda@inktank.com>
Cc: Sage Weil <sage@inktank.com>
Cc: Alex Elder <elder@inktank.com>
Cc: ceph-devel@vger.kernel.org
Cc: Joshua Morris <josh.h.morris@us.ibm.com>
Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: Nagalakshmi Nandigama <Nagalakshmi.Nandigama@lsi.com>
Cc: Sreekanth Reddy <Sreekanth.Reddy@lsi.com>
Cc: support@lsi.com
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Guo Chao <yan@linux.vnet.ibm.com>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Quoc-Son Anh <quoc-sonx.anh@intel.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Seth Jennings <sjenning@linux.vnet.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jan Kara <jack@suse.cz>
Cc: linux-m68k@lists.linux-m68k.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: drbd-user@lists.linbit.com
Cc: nbd-general@lists.sourceforge.net
Cc: cbe-oss-dev@lists.ozlabs.org
Cc: xen-devel@lists.xensource.com
Cc: virtualization@lists.linux-foundation.org
Cc: linux-raid@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: DL-MPTFusionLinux@lsi.com
Cc: linux-scsi@vger.kernel.org
Cc: devel@driverdev.osuosl.org
Cc: linux-fsdevel@vger.kernel.org
Cc: cluster-devel@redhat.com
Cc: linux-mm@kvack.org
Acked-by: Geoff Levand <geoff@infradead.org>
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Immutable biovecs are going to require an explicit iterator. To
implement immutable bvecs, a later patch is going to add a bi_bvec_done
member to this struct; for now, this patch effectively just renames
things.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Ed L. Cashin" <ecashin@coraid.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Yehuda Sadeh <yehuda@inktank.com>
Cc: Sage Weil <sage@inktank.com>
Cc: Alex Elder <elder@inktank.com>
Cc: ceph-devel@vger.kernel.org
Cc: Joshua Morris <josh.h.morris@us.ibm.com>
Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: dm-devel@redhat.com
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: Boaz Harrosh <bharrosh@panasas.com>
Cc: Benny Halevy <bhalevy@tonian.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Dave Kleikamp <shaggy@kernel.org>
Cc: Joern Engel <joern@logfs.org>
Cc: Prasad Joshi <prasadjoshi.linux@gmail.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Ben Myers <bpm@sgi.com>
Cc: xfs@oss.sgi.com
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Guo Chao <yan@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: "Roger Pau Monné" <roger.pau@citrix.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <Ian.Campbell@citrix.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Jerome Marchand <jmarchand@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Peng Tao <tao.peng@emc.com>
Cc: Andy Adamson <andros@netapp.com>
Cc: fanchaoting <fanchaoting@cn.fujitsu.com>
Cc: Jie Liu <jeff.liu@oracle.com>
Cc: Sunil Mushran <sunil.mushran@gmail.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Pankaj Kumar <pankaj.km@samsung.com>
Cc: Dan Magenheimer <dan.magenheimer@oracle.com>
Cc: Mel Gorman <mgorman@suse.de>6
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The probe function is supposed to return NULL on failure (as we can see in
kobj_lookup: kobj = probe(dev, index, data); ... if (kobj) return kobj;
However, in loop and brd, it returns negative error from ERR_PTR.
This causes a crash if we simulate disk allocation failure and run
less -f /dev/loop0 because the negative number is interpreted as a pointer:
BUG: unable to handle kernel NULL pointer dereference at 00000000000002b4
IP: [<ffffffff8118b188>] __blkdev_get+0x28/0x450
PGD 23c677067 PUD 23d6d1067 PMD 0
Oops: 0000 [#1] PREEMPT SMP
Modules linked in: loop hpfs nvidia(PO) ip6table_filter ip6_tables uvesafb cfbcopyarea cfbimgblt cfbfillrect fbcon font bitblit fbcon_rotate fbcon_cw fbcon_ud fbcon_ccw softcursor fb fbdev msr ipt_MASQUERADE iptable_nat nf_nat_ipv4 nf_conntrack_ipv4 nf_defrag_ipv4 xt_state ipt_REJECT xt_tcpudp iptable_filter ip_tables x_tables bridge stp llc tun ipv6 cpufreq_stats cpufreq_ondemand cpufreq_userspace cpufreq_powersave cpufreq_conservative hid_generic spadfs usbhid hid fuse raid0 snd_usb_audio snd_pcm_oss snd_mixer_oss md_mod snd_pcm snd_timer snd_page_alloc snd_hwdep snd_usbmidi_lib dmi_sysfs snd_rawmidi nf_nat_ftp nf_nat nf_conntrack_ftp nf_conntrack snd soundcore lm85 hwmon_vid ohci_hcd ehci_pci ehci_hcd serverworks sata_svw libata acpi_cpufreq freq_table mperf ide_core usbcore kvm_amd kvm tg3 i2c_piix4 libphy microcode e100 usb_common ptp skge i2c_core pcspkr k10temp evdev floppy hwmon pps_core mii rtc_cmos button processor unix [last unloaded: nvidia]
CPU: 1 PID: 6831 Comm: less Tainted: P W O 3.10.15-devel #18
Hardware name: empty empty/S3992-E, BIOS 'V1.06 ' 06/09/2009
task: ffff880203cc6bc0 ti: ffff88023e47c000 task.ti: ffff88023e47c000
RIP: 0010:[<ffffffff8118b188>] [<ffffffff8118b188>] __blkdev_get+0x28/0x450
RSP: 0018:ffff88023e47dbd8 EFLAGS: 00010286
RAX: ffffffffffffff74 RBX: ffffffffffffff74 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffff88023e47dc18 R08: 0000000000000002 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88023f519658
R13: ffffffff8118c300 R14: 0000000000000000 R15: ffff88023f519640
FS: 00007f2070bf7700(0000) GS:ffff880247400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000002b4 CR3: 000000023da1d000 CR4: 00000000000007e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Stack:
0000000000000002 0000001d00000000 000000003e47dc50 ffff88023f519640
ffff88043d5bb668 ffffffff8118c300 ffff88023d683550 ffff88023e47de60
ffff88023e47dc98 ffffffff8118c10d 0000001d81605698 0000000000000292
Call Trace:
[<ffffffff8118c300>] ? blkdev_get_by_dev+0x60/0x60
[<ffffffff8118c10d>] blkdev_get+0x1dd/0x370
[<ffffffff8118c300>] ? blkdev_get_by_dev+0x60/0x60
[<ffffffff813cea6c>] ? _raw_spin_unlock+0x2c/0x50
[<ffffffff8118c300>] ? blkdev_get_by_dev+0x60/0x60
[<ffffffff8118c365>] blkdev_open+0x65/0x80
[<ffffffff8114d12e>] do_dentry_open.isra.18+0x23e/0x2f0
[<ffffffff8114d214>] finish_open+0x34/0x50
[<ffffffff8115e122>] do_last.isra.62+0x2d2/0xc50
[<ffffffff8115eb58>] path_openat.isra.63+0xb8/0x4d0
[<ffffffff81115a8e>] ? might_fault+0x4e/0xa0
[<ffffffff8115f4f0>] do_filp_open+0x40/0x90
[<ffffffff813cea6c>] ? _raw_spin_unlock+0x2c/0x50
[<ffffffff8116db85>] ? __alloc_fd+0xa5/0x1f0
[<ffffffff8114e45f>] do_sys_open+0xef/0x1d0
[<ffffffff8114e559>] SyS_open+0x19/0x20
[<ffffffff813cff16>] system_call_fastpath+0x1a/0x1f
Code: 44 00 00 55 48 89 e5 41 57 49 89 ff 41 56 41 89 d6 41 55 41 54 4c 8d 67 18 53 48 83 ec 18 89 75 cc e9 f2 00 00 00 0f 1f 44 00 00 <48> 8b 80 40 03 00 00 48 89 df 4c 8b 68 58 e8 d5
a4 07 00 44 89
RIP [<ffffffff8118b188>] __blkdev_get+0x28/0x450
RSP <ffff88023e47dbd8>
CR2: 00000000000002b4
---[ end trace bb7f32dbf02398dc ]---
The brd change should be backported to stable kernels starting with 2.6.25.
The loop change should be backported to stable kernels starting with 2.6.22.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: stable@kernel.org # 2.6.22+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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The index on the page must be set before it is inserted in the radix
tree. Otherwise there is a small race which can occur during lookup
where the page can be found with the incorrect index. This will trigger
the BUG_ON() in brd_lookup_page().
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reported-by: Chris Wedgwood <cw@f00f.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Just a little convenience macro - main reason to add it now is preparing
for immutable bio vecs, it'll reduce the size of the patch that puts
bi_sector/bi_size/bi_idx into a struct bvec_iter.
Signed-off-by: Kent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: Lars Ellenberg <drbd-dev@lists.linbit.com>
CC: Jiri Kosina <jkosina@suse.cz>
CC: Alasdair Kergon <agk@redhat.com>
CC: dm-devel@redhat.com
CC: Neil Brown <neilb@suse.de>
CC: Martin Schwidefsky <schwidefsky@de.ibm.com>
CC: Heiko Carstens <heiko.carstens@de.ibm.com>
CC: linux-s390@vger.kernel.org
CC: Chris Mason <chris.mason@fusionio.com>
CC: Steven Whitehouse <swhiteho@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
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Signed-off-by: Cong Wang <amwang@redhat.com>
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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 <npiggin@suse.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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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 <hch@lst.de>
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
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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 <namhyung@gmail.com>
Cc: Laurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
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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 <namhyung@gmail.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
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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 <namhyung@gmail.com>
Cc: Laurent Vivier <Laurent.Vivier@bull.net>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
|
|
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: [<ffffffff81110a9a>] 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:[<ffffffff81110a9a>] [<ffffffff81110a9a>] 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:
[<ffffffff81143c0a>] kobject_add_internal+0xdf/0x1a0
[<ffffffff81143da1>] kobject_add_varg+0x41/0x50
[<ffffffff81143e6b>] kobject_add+0x64/0x66
[<ffffffff8113bbe7>] blk_register_queue+0x5f/0xb8
[<ffffffff81140f72>] add_disk+0xdf/0x289
[<ffffffffa00040df>] brd_init+0xdf/0x1aa [brd]
[<ffffffffa0004000>] ? 0xffffffffa0003fff
[<ffffffffa0004000>] ? 0xffffffffa0003fff
[<ffffffff8100020a>] do_one_initcall+0x7a/0x12e
[<ffffffff8108516c>] sys_init_module+0x9c/0x1dc
[<ffffffff812ff4bb>] 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 [<ffffffff81110a9a>] sysfs_create_dir+0x2d/0xae
RSP <ffff880007b15d78>
CR2: 0000000000000058
---[ end trace aebb1175ce1f6739 ]---
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: Laurent Vivier <Laurent.Vivier@bull.net>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
|
|
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 <namhyung@gmail.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
|
|
* '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
...
|
|
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.*<linux\/smp_lock.h>/d' ${file}
else
sed -i 's/include.*<linux\/smp_lock.h>.*$/include <linux\/mutex.h>/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.*\<smp_lock.h\>/d' ${file} \
-e '/cycle_kernel_lock()/d'
fi
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
|
Barrier is deemed too heavy and will soon be replaced by FLUSH/FUA
requests. Deprecate barrier. All REQ_HARDBARRIERs are failed with
-EOPNOTSUPP and blk_queue_ordered() is replaced with simpler
blk_queue_flush().
blk_queue_flush() takes combinations of REQ_FLUSH and FUA. If a
device has write cache and can flush it, it should set REQ_FLUSH. If
the device can handle FUA writes, it should also set REQ_FUA.
All blk_queue_ordered() users are converted.
* ORDERED_DRAIN is mapped to 0 which is the default value.
* ORDERED_DRAIN_FLUSH is mapped to REQ_FLUSH.
* ORDERED_DRAIN_FLUSH_FUA is mapped to REQ_FLUSH | REQ_FUA.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Boaz Harrosh <bharrosh@panasas.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Alasdair G Kergon <agk@redhat.com>
Cc: Pierre Ossman <drzeus@drzeus.cx>
Cc: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
|
|
Nobody is making meaningful use of ORDERED_BY_TAG now and queue
draining for barrier requests will be removed soon which will render
the advantage of tag ordering moot. Kill ORDERED_BY_TAG. The
following users are affected.
* brd: converted to ORDERED_DRAIN.
* virtio_blk: ORDERED_TAG path was already marked deprecated. Removed.
* xen-blkfront: ORDERED_TAG case dropped.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
|
|
As a preparation for the removal of the big kernel
lock in the block layer, this removes the BKL
from the common ioctl handling code, moving it
into every single driver still using it.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
|
|
This removes q->prepare_flush_fn completely (changes the
blk_queue_ordered API).
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
|
|
Remove the current bio flags and reuse the request flags for the bio, too.
This allows to more easily trace the type of I/O from the filesystem
down to the block driver. There were two flags in the bio that were
missing in the requests: BIO_RW_UNPLUG and BIO_RW_AHEAD. Also I've
renamed two request flags that had a superflous RW in them.
Note that the flags are in bio.h despite having the REQ_ name - as
blkdev.h includes bio.h that is the only way to go for now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
|
|
Support discard requests in brd by zeroing or deleting the underlying backing
pages. This is simply to help with testing and documentation nature of
brd code.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
|
|
implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
|
|
The block layer calling convention is blk_queue_<limit name>.
blk_queue_max_sectors predates this practice, leading to some confusion.
Rename the function to appropriately reflect that its intended use is to
set max_hw_sectors.
Also introduce a temporary wrapper for backwards compability. This can
be removed after the merge window is closed.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
|
|
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
The "ramdisk" parameter was removed from the defunct rd.c file quite some
time ago, in favour of the more specific "ramdisk_size" parameter so, for
consistency, the same should be done here.
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Acked-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
|
|
brd is missing a flush_dcache_page. On 2nd thoughts, perhaps it is the
pagecache's responsibility to flush user virtual aliases (the driver of
course should flush kernel virtual mappings)... but anyway, there
already exists cache flushing for one direction of transfer, so we
should add the other.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
|
|
brd is always ordered (not that it matters, as it is defined not to
survive when the system goes down). So tell the block layer it is
ordered, which might be of help with testing filesystems.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
|
|
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
|
To keep the size of changesets sane we split the switch by drivers;
to keep the damn thing bisectable we do the following:
1) rename the affected methods, add ones with correct
prototypes, make (few) callers handle both. That's this changeset.
2) for each driver convert to new methods. *ALL* drivers
are converted in this series.
3) kill the old (renamed) methods.
Note that it _is_ a flagday; all in-tree drivers are converted and by the
end of this series no trace of old methods remain. The only reason why
we do that this way is to keep the damn thing bisectable and allow per-driver
debugging if anything goes wrong.
New methods:
open(bdev, mode)
release(disk, mode)
ioctl(bdev, mode, cmd, arg) /* Called without BKL */
compat_ioctl(bdev, mode, cmd, arg)
locked_ioctl(bdev, mode, cmd, arg) /* Called with BKL, legacy */
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
|
The name of brd block device is "ramdisk", it's not "brd".
(The block device is registered by register_blkdev(RAMDISK_MAJOR, "ramdisk")
So it should be unregistered by unregister_blkdev(RAMDISK_MAJOR, "ramdisk")
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Alias brd to rd in the hope of helping legacy users. Suggested by Jan.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
In 2.6.25, ramdisk devices show up in /proc/partitions, which is a
behaviour change from the old rd.c. Add GENHD_FL_SUPPRESS_PARTITION_INFO,
which was present in rd.c.
All kernels prior to 2.6.25 weren't displaying ramdisks in
/proc/partitions. Since there are many userspace tools using information
from /proc/partitions some of them may now behave incorrectly (I didn't
tested any though). For example before 2.6.25 /proc/partitions was empty
if no block devices like hard disks and such were detected by kernel. Now
all 16 ramdisks are always visible there. Some software may rely on such
information (I mean, on empty /proc/partitions).
There was quite similar situation back in 2004, and ramdisks were excluded
back from displaying. Thats why I called this a regression (maybe a bit
unfortunate). See this patch for info:
http://kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.3-rc2/2.6.3-rc2-mm1/broken-out/nbd-proc-partitions-fix.patch
I also think that someone somewhere (long time ago) excluded ramdisks from
/proc/partitions for good reasons. It is possible that now such new
"feature" is harmless, but I think there are more chances that someone
will say "hey, /proc/partitions has changed, now my software doesn't work"
then "hey where did my new 2.6.25 feature go". nbd devices are also
excluded, maybe for very same (unknown to me) reasons.
Signed-off-by: Marcin Krol <hawk@pld-linux.org>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
This patch adds partition management for Block RAM Device (BRD).
This patch is done to keep in sync BRD and loop device drivers.
This patch adds a parameter to the module, max_part, to specify
the maximum number of partitions per RAM device.
Example:
# modprobe brd max_part=63
# ls -l /dev/ram*
brw-rw---- 1 root disk 1, 0 2008-04-03 13:39 /dev/ram0
brw-rw---- 1 root disk 1, 64 2008-04-03 13:39 /dev/ram1
brw-rw---- 1 root disk 1, 640 2008-04-03 13:39 /dev/ram10
brw-rw---- 1 root disk 1, 704 2008-04-03 13:39 /dev/ram11
brw-rw---- 1 root disk 1, 768 2008-04-03 13:39 /dev/ram12
brw-rw---- 1 root disk 1, 832 2008-04-03 13:39 /dev/ram13
brw-rw---- 1 root disk 1, 896 2008-04-03 13:39 /dev/ram14
brw-rw---- 1 root disk 1, 960 2008-04-03 13:39 /dev/ram15
brw-rw---- 1 root disk 1, 128 2008-04-03 13:39 /dev/ram2
brw-rw---- 1 root disk 1, 192 2008-04-03 13:39 /dev/ram3
brw-rw---- 1 root disk 1, 256 2008-04-03 13:39 /dev/ram4
brw-rw---- 1 root disk 1, 320 2008-04-03 13:39 /dev/ram5
brw-rw---- 1 root disk 1, 384 2008-04-03 13:39 /dev/ram6
brw-rw---- 1 root disk 1, 448 2008-04-03 13:39 /dev/ram7
brw-rw---- 1 root disk 1, 512 2008-04-03 13:39 /dev/ram8
brw-rw---- 1 root disk 1, 576 2008-04-03 13:39 /dev/ram9
# fdisk /dev/ram0
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel. Changes will remain in memory only,
until you decide to write them. After that, of course, the previous
content won't be recoverable.
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
Command (m for help): o
Building a new DOS disklabel. Changes will remain in memory only,
until you decide to write them. After that, of course, the previous
content won't be recoverable.
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-2, default 1): 1
Last cylinder or +size or +sizeM or +sizeK (1-2, default 2): 2
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
# ls -l /dev/ram0*
brw-rw---- 1 root disk 1, 0 2008-04-03 13:40 /dev/ram0
brw-rw---- 1 root disk 1, 1 2008-04-03 13:40 /dev/ram0p1
# mkfs /dev/ram0p1
mke2fs 1.40-WIP (14-Nov-2006)
Filesystem label=
OS type: Linux
Block size=1024 (log=0)
Fragment size=1024 (log=0)
4016 inodes, 16032 blocks
801 blocks (5.00%) reserved for the super user
First data block=1
Maximum filesystem blocks=16515072
2 block groups
8192 blocks per group, 8192 fragments per group
2008 inodes per group
Superblock backups stored on blocks:
8193
Writing inode tables: done
Writing superblocks and filesystem accounting information: done
This filesystem will be automatically checked every 26 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
# mount /dev/ram0p1 /mnt
df /mnt
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/ram0p1 15521 138 14582 1% /mnt
# ls -l /mnt
total 12
drwx------ 2 root root 12288 2008-04-03 13:41 lost+found
# umount /mnt
# rmmod brd
Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Acked-by: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Alter the block device ->direct_access() API to work with the new
get_xip_mem() API (that requires both kaddr and pfn are returned).
Some architectures will not do the right thing in their virt_to_page() for use
by XIP (to translate from the kernel virtual address returned by
direct_access(), to a user mappable pfn in XIP's page fault handler.
However, we can't switch it to just return the pfn and not the kaddr, because
we have no good way to get a kva from a pfn, and XIP requires the kva for its
read(2) and write(2) handlers. So we have to return both.
Signed-off-by: Jared Hulbert <jaredeh@gmail.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-mm@kvack.org
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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While looking at the implementation of the Ram backed block device
driver, I stumbled across a write-only local variable, which makes
little sense, so I assume it should actually work like this:
Signed-off-by: Petr Tesarik <ptesarik@suse.cz>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Support direct_access XIP method with brd.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This is a rewrite of the ramdisk block device driver.
The old one is really difficult because it effectively implements a block
device which serves data out of its own buffer cache. It relies on the dirty
bit being set, to pin its backing store in cache, however there are non
trivial paths which can clear the dirty bit (eg. try_to_free_buffers()),
which had recently lead to data corruption. And in general it is completely
wrong for a block device driver to do this.
The new one is more like a regular block device driver. It has no idea about
vm/vfs stuff. It's backing store is similar to the buffer cache (a simple
radix-tree of pages), but it doesn't know anything about page cache (the pages
in the radix tree are not pagecache pages).
There is one slight downside -- direct block device access and filesystem
metadata access goes through an extra copy and gets stored in RAM twice.
However, this downside is only slight, because the real buffercache of the
device is now reclaimable (because we're not playing crazy games with it), so
under memory intensive situations, footprint should effectively be the same --
maybe even a slight advantage to the new driver because it can also reclaim
buffer heads.
The fact that it now goes through all the regular vm/fs paths makes it
much more useful for testing, too.
text data bss dec hex filename
2837 849 384 4070 fe6 drivers/block/rd.o
3528 371 12 3911 f47 drivers/block/brd.o
Text is larger, but data and bss are smaller, making total size smaller.
A few other nice things about it:
- Similar structure and layout to the new loop device handlinag.
- Dynamic ramdisk creation.
- Runtime flexible buffer head size (because it is no longer part of the
ramdisk code).
- Boot / load time flexible ramdisk size, which could easily be extended
to a per-ramdisk runtime changeable size (eg. with an ioctl).
- Can use highmem for the backing store.
[akpm@linux-foundation.org: fix build]
[byron.bbradley@gmail.com: make rd_size non-static]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Byron Bradley <byron.bbradley@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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