This change is in a conditional block which is entered only when there is
an existing data block on the freelist where the insert has taken place.
The new block is pushed onto the freelist stack and this conditional block
is updating links in the prior stack head to point to the new stack head.
After this conditional block the first-/second-level indices are updated
to indicate that there is a free block at this location.
This patch adds an immediate return from the conditional block to avoid
setting bits again to indicate a free block on this freelist. The bits
would already be set because there was an existing free block on this
freelist.
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
On a 64K page kernel, the value PAGE_SIZE passed to
blk_queue_logical_block_size would overflow the logical block size
argument (resulting in setting it to 0).
This patch sets the logical block size to 4096, using a new
ZRAM_LOGICAL_BLOCK_SIZE constant.
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
xvmalloc will not currently function with 64K pages. Newly allocated
pages will be inserted at an offset beyond the end of the first-level
index. This tuning is needed to properly size the allocator for 64K
pages.
The default 3 byte shift results in a second level list size which can not
be indexed using the 64 bits of the flbitmap in the xv_pool structure.
The shift must increase to 4 bytes between second level list entries to
fit the size of the first level bitmap.
Here are a few statistics for structure sizes on 32- and 64-bit CPUs
with 4KB and 64KB page sizes.
bits_per_long 32 64 64
page_size 4,096 4,096 65,535
xv_align 4 8 8
fl_delta 3 3 4
num_free_lists 508 508 4,094
xv_pool size 4,144b 8,216b 66,040b
per object overhead 32 64 64
zram struct 0.5GB disk 512KB 1024KB 64KB
This patch maintains the current tunings for 4K pages, adds an optimal
sizing for 64K pages and adds a safe tuning for any other page sizes.
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
zram_read() and zram_write() always return zero, so make them return
void to simplify the code.
Signed-off-by: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Not exactly sure if this is a typo or not, due to my search
results comming up with not that many hits. Either its dereferenceable
or dereferencable from the two I choose the later. if it's wrong let me know
and I'll resend.
Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Make zram_read() return a bio error if the device is not initialized
instead of pretending nothing happened.
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Currently disksize_store() round down the disk size provided by user.
This is probably not what one would expect, so round up instead.
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We can not configure zram device without sysfs anyway, so make zram
depends on it.
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This reverts commit 7e24cce38a99f373450db67bf576fe73e8168d66 because it
was never appropriate for mainline.
Do not check for init flag before starting I/O - zram module is unusable
without this fix.
The oops mentioned in the reverted commit message was actually a problem
only with the zram version as present in project's own repository where
we allocate struct zram_stats_cpu upon device initialization. OTOH, In
mainline/staging version of zram, we allocate struct stats upfront, so
this oops cannot happen in mainline version.
Checking for init_done flag in zram_make_request() results in a *no-op*
for any I/O operation since we simply always return success. This flag
is actually set when the first write occurs on a zram disk which
triggers its initialization.
Bug report: https://bugzilla.kernel.org/show_bug.cgi?id=25722
Reported-by: Dennis Jansen <dennis.jansen@web.de>
Signed-off-by: Nitin Gupta <ngupta@vflare.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch fixes the warning generated by sparse: "Using plain integer
as NULL pointer" by replacing the offending 0s with NULL.
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This was done to handle a number of conflicts in the batman-adv
and winbond drivers properly. It also now allows us to fix up the sysfs
attributes properly that were not in the .37 release due to them being
only in this tree at the time.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
They should be writable by root, not readable.
Doh, stupid me with the wrong flags.
Reported-by: Jonathan Cameron <jic23@cam.ac.uk>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
They should not be writable by any user
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This merges the staging-next tree to Linus's tree and resolves
some conflicts that were present due to changes in other trees that were
affected by files here.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
I'm getting an oops when running mkfs on zram:
NIP [d0000000030e0340] .zram_inc_stat+0x58/0x84 [zram]
[c00000006d58f720] [d0000000030e091c] .zram_make_request+0xa8/0x6a0 [zram]
[c00000006d58f840] [c00000000035795c] .generic_make_request+0x390/0x434
[c00000006d58f950] [c000000000357b14] .submit_bio+0x114/0x140
[c00000006d58fa20] [c000000000361778] .blkdev_issue_discard+0x1ac/0x250
[c00000006d58fb10] [c000000000361f68] .blkdev_ioctl+0x358/0x7fc
[c00000006d58fbd0] [c0000000001c1c1c] .block_ioctl+0x6c/0x90
[c00000006d58fc70] [c0000000001984c4] .do_vfs_ioctl+0x660/0x6d4
[c00000006d58fd70] [c0000000001985a0] .SyS_ioctl+0x68/0xb0
Since disksize no longer starts as 0 it looks like we can call
zram_make_request before the device has been initialised. The patch below
fixes the immediate problem but this would go away if we move the
initialisation function elsewhere (as suggested in another thread).
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Currently, the user has to explicitly write a positive value to
initstate sysfs node before the device can be used. This event
triggers allocation of per-device metadata like memory pool,
table array and so on.
We do not pre-initialize all zram devices since the 'table' array,
mapping disk blocks to compressed chunks, takes considerable amount
of memory (8 bytes per page). So, pre-initializing all devices will
be quite wasteful if only few or none of the devices are actually
used.
This explicit device initialization from user is an odd requirement and
can be easily avoided. We now initialize the device when first write is
done to the device.
Signed-off-by: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Creates per-device sysfs nodes in /sys/block/zram<id>/
Currently following stats are exported:
- disksize
- num_reads
- num_writes
- invalid_io
- zero_pages
- orig_data_size
- compr_data_size
- mem_used_total
By default, disksize is set to 0. So, to start using
a zram device, fist write a disksize value and then
initialize device by writing any positive value to
initstate. For example:
# initialize /dev/zram0 with 50MB disksize
echo 50*1024*1024 | bc > /sys/block/zram0/disksize
echo 1 > /sys/block/zram0/initstate
When done using a disk, issue reset to free its memory
by writing any positive value to reset node:
echo 1 > /sys/block/zram0/reset
This change also obviates the need for 'rzscontrol' utility.
Signed-off-by: Nitin Gupta <ngupta@vflare.org>
Acked-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Fix 49 zram build errors in one swoop. Examples:
drivers/staging/zram/zram_drv.c:225: error: dereferencing pointer to incomplete type
drivers/staging/zram/zram_drv.c:226: error: implicit declaration of function 'bio_for_each_segment'
drivers/staging/zram/zram_drv.c:226: error: expected ';' before '{' token
drivers/staging/zram/zram_drv.c:281: error: implicit declaration of function 'bio_endio'
drivers/staging/zram/zram_drv.c:285: error: implicit declaration of function 'bio_io_error'
drivers/staging/zram/zram_drv.c:545: error: implicit declaration of function 'set_capacity'
drivers/staging/zram/zram_drv.c:548: error: implicit declaration of function 'queue_flag_set_unlocked'
drivers/staging/zram/zram_drv.c:548: error: 'QUEUE_FLAG_NONROT' undeclared (first use in this function)
drivers/staging/zram/zram_drv.c:548: error: dereferencing pointer to incomplete type
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Related changes:
- Included example to show usage as generic
(non-swap) disk with ext4 filesystem.
- Renamed rzscontrol to zramconfig to match
with new device naming.
Signed-off-by: Nitin Gupta <ngupta@vflare.org>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Related changes:
- Modify revelant Kconfig and Makefile accordingly.
- Change include filenames in code.
- Remove dependency on CONFIG_SWAP in Kconfig as zram usage
is no longer limited to swap disks.
Signed-off-by: Nitin Gupta <ngupta@vflare.org>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
