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| author | Paolo Bonzini <pbonzini@redhat.com> | 2013-02-08 14:06:14 +0100 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2013-02-22 21:29:44 +0100 |
| commit | 215e47b9ea2cd7926333b7dc683024aa00e0c386 (patch) | |
| tree | d1ae0848fbdfc0ef88ac9d87abc23171fde3d6cb /hw/scsi-disk.c | |
| parent | ded9d2d5e247dc4d141c01bc8dc99d6ec832f9e8 (diff) | |
| download | qemu-215e47b9ea2cd7926333b7dc683024aa00e0c386.tar.gz qemu-215e47b9ea2cd7926333b7dc683024aa00e0c386.tar.bz2 qemu-215e47b9ea2cd7926333b7dc683024aa00e0c386.zip | |
blockdev: enable discard by default
Because discard is now a host parameter, we can always fake it as enabled
in the guest. This is an extension of the current choice to ignore
"not supported" errors from the host when discard_granularity is set
to nonzero.
The default granularity is set to the logical block size or 4k, whichever
is largest, because cluster sizes below 4k are rarely used and 4K is a
typical block size for files.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'hw/scsi-disk.c')
| -rw-r--r-- | hw/scsi-disk.c | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/hw/scsi-disk.c b/hw/scsi-disk.c index 28e75bbf5b..d41158693e 100644 --- a/hw/scsi-disk.c +++ b/hw/scsi-disk.c @@ -41,9 +41,11 @@ do { printf("scsi-disk: " fmt , ## __VA_ARGS__); } while (0) #include <scsi/sg.h> #endif -#define SCSI_DMA_BUF_SIZE 131072 -#define SCSI_MAX_INQUIRY_LEN 256 -#define SCSI_MAX_MODE_LEN 256 +#define SCSI_DMA_BUF_SIZE 131072 +#define SCSI_MAX_INQUIRY_LEN 256 +#define SCSI_MAX_MODE_LEN 256 + +#define DEFAULT_DISCARD_GRANULARITY 4096 typedef struct SCSIDiskState SCSIDiskState; @@ -2059,6 +2061,11 @@ static int scsi_initfn(SCSIDevice *dev) return -1; } + if (s->qdev.conf.discard_granularity == -1) { + s->qdev.conf.discard_granularity = + MAX(s->qdev.conf.logical_block_size, DEFAULT_DISCARD_GRANULARITY); + } + if (!s->version) { s->version = g_strdup(qemu_get_version()); } |