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LVM2 ./WHATS_NEW doc/example.conf.in lib/confi ...
- From: snitzer at sourceware dot org
- To: lvm-devel at redhat dot com, lvm2-cvs at sourceware dot org
- Date: 12 Apr 2011 21:59:05 -0000
- Subject: LVM2 ./WHATS_NEW doc/example.conf.in lib/confi ...
CVSROOT: /cvs/lvm2
Module name: LVM2
Changes by: snitzer@sourceware.org 2011-04-12 21:59:02
Modified files:
. : WHATS_NEW
doc : example.conf.in
lib/config : defaults.h
lib/device : dev-io.c device.c device.h
lib/metadata : pv_manip.c
man : lvm.conf.5.in
Log message:
Add "devices/issue_discards" to lvm.conf.
Issue discards on lvremove if enabled and both storage and kernel have support.
Patches:
http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/WHATS_NEW.diff?cvsroot=lvm2&r1=1.1970&r2=1.1971
http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/doc/example.conf.in.diff?cvsroot=lvm2&r1=1.20&r2=1.21
http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/lib/config/defaults.h.diff?cvsroot=lvm2&r1=1.72&r2=1.73
http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/lib/device/dev-io.c.diff?cvsroot=lvm2&r1=1.75&r2=1.76
http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/lib/device/device.c.diff?cvsroot=lvm2&r1=1.37&r2=1.38
http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/lib/device/device.h.diff?cvsroot=lvm2&r1=1.47&r2=1.48
http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/lib/metadata/pv_manip.c.diff?cvsroot=lvm2&r1=1.28&r2=1.29
http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/man/lvm.conf.5.in.diff?cvsroot=lvm2&r1=1.18&r2=1.19
--- LVM2/WHATS_NEW 2011/04/09 19:05:23 1.1970
+++ LVM2/WHATS_NEW 2011/04/12 21:59:01 1.1971
@@ -1,5 +1,7 @@
Version 2.02.85 -
===================================
+ Add "devices/issue_discards" to lvm.conf.
+ Issue discards on lvremove if enabled and both storage and kernel have support.
Fix incorrect tests for dm_snprintf() failure.
Fix some unmatching sign comparation gcc warnings in the code.
Allow lv_extend() to work on zero length intrinsically layered LVs.
--- LVM2/doc/example.conf.in 2011/04/12 20:44:41 1.20
+++ LVM2/doc/example.conf.in 2011/04/12 21:59:01 1.21
@@ -151,6 +151,14 @@
# Example: Ignore devices smaller than 2MB (i.e. floppy drives).
# pv_min_size = 2048
pv_min_size = 512
+
+ # Issue discards to an LV's underlying PV(s) when the LV is removed.
+ # Discards inform the storage that a region is no longer in use. If set
+ # to 1, discards will only be issued if both the storage and kernel provide
+ # support. Not all storage will support or benefit from discards but SSDs
+ # or thinly provisioned LUNs generally do.
+ # 1 enables; 0 disables.
+ issue_discards = 0
}
# This section allows you to configure the way in which LVM selects
--- LVM2/lib/config/defaults.h 2011/02/27 00:38:32 1.72
+++ LVM2/lib/config/defaults.h 2011/04/12 21:59:01 1.73
@@ -37,6 +37,7 @@
#define DEFAULT_REQUIRE_RESTOREFILE_WITH_UUID 1
#define DEFAULT_DATA_ALIGNMENT_OFFSET_DETECTION 1
#define DEFAULT_DATA_ALIGNMENT_DETECTION 1
+#define DEFAULT_ISSUE_DISCARDS 0
#define DEFAULT_LOCKING_LIB "liblvm2clusterlock.so"
#define DEFAULT_FALLBACK_TO_LOCAL_LOCKING 1
--- LVM2/lib/device/dev-io.c 2011/03/29 20:19:03 1.75
+++ LVM2/lib/device/dev-io.c 2011/04/12 21:59:01 1.76
@@ -36,6 +36,9 @@
# ifndef BLKGETSIZE64 /* fs.h out-of-date */
# define BLKGETSIZE64 _IOR(0x12, 114, size_t)
# endif /* BLKGETSIZE64 */
+# ifndef BLKDISCARD
+# define BLKDISCARD _IO(0x12,119)
+# endif
#else
# include <sys/disk.h>
# define BLKBSZGET DKIOCGETBLOCKSIZE
@@ -301,6 +304,33 @@
return 1;
}
+static int _dev_discard_blocks(struct device *dev, uint64_t offset_bytes, uint64_t size_bytes)
+{
+ uint64_t discard_range[2];
+
+ if (!dev_open(dev))
+ return_0;
+
+ discard_range[0] = offset_bytes;
+ discard_range[1] = size_bytes;
+
+ log_debug("Discarding %" PRIu64 " bytes offset %" PRIu64 " bytes on %s.",
+ size_bytes, offset_bytes, dev_name(dev));
+ if (ioctl(dev->fd, BLKDISCARD, &discard_range) < 0) {
+ log_error("%s: BLKDISCARD ioctl at offset %" PRIu64 " size %" PRIu64 " failed: %s.",
+ dev_name(dev), offset_bytes, size_bytes, strerror(errno));
+ if (!dev_close(dev))
+ stack;
+ /* It doesn't matter if discard failed, so return success. */
+ return 1;
+ }
+
+ if (!dev_close(dev))
+ stack;
+
+ return 1;
+}
+
/*-----------------------------------------------------------------
* Public functions
*---------------------------------------------------------------*/
@@ -329,6 +359,17 @@
return _dev_read_ahead_dev(dev, read_ahead);
}
+int dev_discard_blocks(struct device *dev, uint64_t offset_bytes, uint64_t size_bytes)
+{
+ if (!dev)
+ return 0;
+
+ if (dev->flags & DEV_REGULAR)
+ return 1;
+
+ return _dev_discard_blocks(dev, offset_bytes, size_bytes);
+}
+
/* FIXME Unused
int dev_get_sectsize(struct device *dev, uint32_t *size)
{
--- LVM2/lib/device/device.c 2011/03/13 22:52:20 1.37
+++ LVM2/lib/device/device.c 2011/04/12 21:59:01 1.38
@@ -455,6 +455,20 @@
sysfs_dir, dev);
}
+unsigned long dev_discard_max_bytes(const char *sysfs_dir,
+ struct device *dev)
+{
+ return _dev_topology_attribute("queue/discard_max_bytes",
+ sysfs_dir, dev);
+}
+
+unsigned long dev_discard_granularity(const char *sysfs_dir,
+ struct device *dev)
+{
+ return _dev_topology_attribute("queue/discard_granularity",
+ sysfs_dir, dev);
+}
+
#else
int get_primary_dev(const char *sysfs_dir,
@@ -481,4 +495,16 @@
return 0UL;
}
+unsigned long dev_discard_max_bytes(const char *sysfs_dir,
+ struct device *dev)
+{
+ return 0UL;
+}
+
+unsigned long dev_discard_granularity(const char *sysfs_dir,
+ struct device *dev)
+{
+ return 0UL;
+}
+
#endif
--- LVM2/lib/device/device.h 2011/02/18 23:09:55 1.47
+++ LVM2/lib/device/device.h 2011/04/12 21:59:01 1.48
@@ -68,6 +68,7 @@
int dev_get_size(const struct device *dev, uint64_t *size);
int dev_get_sectsize(struct device *dev, uint32_t *size);
int dev_get_read_ahead(struct device *dev, uint32_t *read_ahead);
+int dev_discard_blocks(struct device *dev, uint64_t offset_bytes, uint64_t size_bytes);
/* Use quiet version if device number could change e.g. when opening LV */
int dev_open(struct device *dev);
@@ -115,4 +116,10 @@
unsigned long dev_optimal_io_size(const char *sysfs_dir,
struct device *dev);
+unsigned long dev_discard_max_bytes(const char *sysfs_dir,
+ struct device *dev);
+
+unsigned long dev_discard_granularity(const char *sysfs_dir,
+ struct device *dev);
+
#endif
--- LVM2/lib/metadata/pv_manip.c 2011/03/29 20:19:04 1.28
+++ LVM2/lib/metadata/pv_manip.c 2011/04/12 21:59:01 1.29
@@ -20,6 +20,7 @@
#include "archiver.h"
#include "locking.h"
#include "lvmcache.h"
+#include "defaults.h"
static struct pv_segment *_alloc_pv_segment(struct dm_pool *mem,
struct physical_volume *pv,
@@ -190,12 +191,38 @@
int release_pv_segment(struct pv_segment *peg, uint32_t area_reduction)
{
+ uint64_t discard_offset;
+ uint64_t pe_start = peg->pv->pe_start;
+ uint64_t discard_area_reduction = area_reduction;
+
if (!peg->lvseg) {
log_error("release_pv_segment with unallocated segment: "
"%s PE %" PRIu32, pv_dev_name(peg->pv), peg->pe);
return 0;
}
+ /*
+ * Only issue discards if enabled in lvm.conf and both
+ * the device and kernel (>= 2.6.35) supports discards.
+ */
+ if (find_config_tree_bool(peg->pv->fmt->cmd,
+ "devices/issue_discards", DEFAULT_ISSUE_DISCARDS) &&
+ dev_discard_max_bytes(peg->pv->fmt->cmd->sysfs_dir, peg->pv->dev) &&
+ dev_discard_granularity(peg->pv->fmt->cmd->sysfs_dir, peg->pv->dev)) {
+ if (!pe_start) {
+ /* skip the first extent */
+ pe_start = peg->pv->vg->extent_size;
+ discard_area_reduction--;
+ }
+ discard_offset = peg->pe + peg->lvseg->area_len - area_reduction;
+ discard_offset = (discard_offset * peg->pv->vg->extent_size) + pe_start;
+ log_debug("Discarding %" PRIu32 " extents offset %" PRIu64 " sectors on %s.",
+ discard_area_reduction, discard_offset, dev_name(peg->pv->dev));
+ if (!dev_discard_blocks(peg->pv->dev, discard_offset << SECTOR_SHIFT,
+ discard_area_reduction * peg->pv->vg->extent_size * SECTOR_SIZE))
+ return_0;
+ }
+
if (peg->lvseg->area_len == area_reduction) {
peg->pv->pe_alloc_count -= area_reduction;
peg->lvseg->lv->vg->free_count += area_reduction;
--- LVM2/man/lvm.conf.5.in 2011/04/12 21:21:08 1.18
+++ LVM2/man/lvm.conf.5.in 2011/04/12 21:59:02 1.19
@@ -180,6 +180,13 @@
.IP
pv_min_size = 2048
.IP
+\fBissue_discards\fP \(em
+Issue discards to an LV's underlying PV(s) when the LV is removed. Discards
+inform the storage that a region is no longer in use. If set to 1, discards will
+only be issued if both the storage and kernel provide support. Not all storage
+will support or benefit from discards but SSDs or thinly provisioned LUNs
+generally do.
+.IP
.TP
\fBallocation\fP \(em Space allocation policies
.IP