On Sun, 1 Apr 2012 08:26:27 +1000
ronnie sahlberg <ronniesahlberg@xxxxxxxxx> wrote:
> From 2830abc3935294eba621b781f72aecda604c65a7 Mon Sep 17 00:00:00 2001
> From: Ronnie Sahlberg <ronniesahlberg@xxxxxxxxx>
> Date: Sun, 1 Apr 2012 08:04:06 +1000
> Subject: [PATCH 2/2] SBC UNMAP: Add support for thin-provisioning and the UNMAP command.
>
> The UNMAP command is implemented using FALLOC_FL_PUNCH_HOLE and will
> release UNMAPPED blocks back to the underlying filesystem.
>
> FALLOC_FL_PUNCH_HOLE is fairly new addition to Linux but works on
> ext4 and XFS filesystems currently.
>
> Signed-off-by: Ronnie Sahlberg <ronniesahlberg@xxxxxxxxx>
> ---
> doc/tgtadm.8.xml | 25 ++++++++++++++
> usr/bs_rdwr.c | 97 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
> usr/sbc.c | 76 +++++++++++++++++++++++++++++++++++++++++-
> usr/scsi.h | 1 +
> usr/spc.c | 43 +++++++++++++++++++++--
> usr/target.c | 2 +
> usr/tgtd.h | 2 +
> 7 files changed, 241 insertions(+), 5 deletions(-)
>
> diff --git a/doc/tgtadm.8.xml b/doc/tgtadm.8.xml
> index 668e184..a40f659 100644
> --- a/doc/tgtadm.8.xml
> +++ b/doc/tgtadm.8.xml
> @@ -352,6 +352,31 @@ tgtadm --lld iscsi --mode logicalunit --op update --tid 1 --lun 1 \
> --params readonly=1
> </screen>
>
> + <varlistentry><term><option>thin_provisioning=<0|1></option></term>
> + <listitem>
> + <para>
> + This controls the provisioning for the LUN. A thin-provisioned
> + LUN is represented as a sparse file.
> + TGTD supports provisioning type 2 for sparse files.
> + When initiators use the SCSI UNMAP command TGTD will release
> + the affected areas back to the filesystem using
> + FALLOC_FL_PUNCH_HOLE.
> + </para>
> + <para>
> + This parameter only applies to DISK devices.
> + </para>
> + <para>
> + Thin-provisioning only works for LUNs stored on filesystems
> + that support FALLOC_FL_PUNCH_HOLE.
> + </para>
> + </listitem>
> + </varlistentry>
> +
> + <screen format="linespecific">
> +tgtadm --lld iscsi --mode logicalunit --op update --tid 1 --lun 1 \
> + --params thin_provisioning=1
> + </screen>
Users need to enable this explicitly?
I mean that when a lu is added, tgtd can check if the backing storage
supports FALLOC_FL_PUNCH_HOLE then enables it automatically?
> </variablelist>
> </refsect1>
>
> diff --git a/usr/bs_rdwr.c b/usr/bs_rdwr.c
> index 84ed278..7d614f8 100644
> --- a/usr/bs_rdwr.c
> +++ b/usr/bs_rdwr.c
> @@ -27,6 +27,8 @@
> #include <stdio.h>
> #include <stdlib.h>
> #include <string.h>
> +#include <sys/types.h>
> +#include <sys/stat.h>
> #include <unistd.h>
>
> #include <linux/fs.h>
> @@ -63,6 +65,7 @@ static void bs_rdwr_request(struct scsi_cmd *cmd)
> uint8_t key;
> uint16_t asc;
> char *tmpbuf;
> + struct stat st;
>
> ret = length = 0;
> key = asc = 0;
> @@ -160,6 +163,100 @@ static void bs_rdwr_request(struct scsi_cmd *cmd)
>
> free(tmpbuf);
> break;
> + case UNMAP:
> + if (!cmd->dev->attrs.thinprovisioning) {
> + result = SAM_STAT_CHECK_CONDITION;
> + key = ILLEGAL_REQUEST;
> + asc = ASC_INVALID_FIELD_IN_CDB;
> + break;
> + }
> +
> + if (fstat(fd, &st) != 0) {
> + eprintf("Failed to fstat() file for UNMAP\n");
> + result = SAM_STAT_CHECK_CONDITION;
> + key = HARDWARE_ERROR;
> + asc = ASC_INTERNAL_TGT_FAILURE;
> + break;
> + }
> +
> + length = scsi_get_out_length(cmd);
> + tmpbuf = scsi_get_out_buffer(cmd);
> +
> + if (length < 8)
> + break;
> +
> + length -= 8;
> + tmpbuf += 8;
> +
> + while (length >= 16) {
> + uint64_t offset;
> + uint64_t len;
> +
> + offset = get_unaligned_be64(&tmpbuf[0]);
> + offset = offset << cmd->dev->blk_shift;
> +
> + len = get_unaligned_be32(&tmpbuf[8]);
> + len = len << cmd->dev->blk_shift;
> +
> + if (offset + len > st.st_size) {
> + eprintf("UNMAP beyond EOF\n");
> + result = SAM_STAT_CHECK_CONDITION;
> + key = ILLEGAL_REQUEST;
> + asc = ASC_LBA_OUT_OF_RANGE;
> + break;
> + }
> +
> + /* we can only punch holes aligned for full blocks.
> + * if not aligned to a block boundary we overwrite
> + * the first partial block with zero
> + */
> + if (len > 0 && offset % st.st_blksize) {
> + char *buf;
> + uint64_t l;
> +
> + l = st.st_blksize - offset % st.st_blksize;
> + if (l > len)
> + l = len;
> +
> + buf = zalloc(l);
> + pwrite64(fd, buf, l, offset);
> + free(buf);
> +
> + offset += l;
> + len -= l;
> + }
> +
> + if (len >= st.st_blksize) {
> + if (unmap_file_region(fd, offset,
> + len - len % st.st_blksize) != 0) {
> + eprintf("Failed to punch hole for"
> + " UNMAP at offset:" PRIu64
> + " length: " PRIu64 "\n",
> + offset,
> + len - len % st.st_blksize);
> + result = SAM_STAT_CHECK_CONDITION;
> + key = HARDWARE_ERROR;
> + asc = ASC_INTERNAL_TGT_FAILURE;
> + break;
> + }
> + offset += len - len % st.st_blksize;
> + len = len % st.st_blksize;
> +
> + }
> +
> + /* zero the tail if there is one */
> + if (len > 0) {
> + char *buf;
> +
> + buf = zalloc(len);
> + pwrite64(fd, buf, len, offset);
> + free(buf);
> + }
> +
> + length -= 16;
> + tmpbuf += 16;
> + }
> + break;
> default:
> break;
> }
> diff --git a/usr/sbc.c b/usr/sbc.c
> index 0c3681e..c93d5de 100644
> --- a/usr/sbc.c
> +++ b/usr/sbc.c
> @@ -141,6 +141,60 @@ sense:
> return SAM_STAT_CHECK_CONDITION;
> }
>
> +static int sbc_unmap(int host_no, struct scsi_cmd *cmd)
> +{
> + int ret;
> + unsigned char key = ILLEGAL_REQUEST;
> + uint16_t asc = ASC_LUN_NOT_SUPPORTED;
> + struct scsi_lu *lu = cmd->dev;
> + int anchor;
> +
> + ret = device_reserved(cmd);
> + if (ret)
> + return SAM_STAT_RESERVATION_CONFLICT;
> +
> + /* We dont support anchored blocks */
> + anchor = cmd->scb[1] & 0x01;
> + if (anchor) {
> + key = ILLEGAL_REQUEST;
> + asc = ASC_INVALID_FIELD_IN_CDB;
> + goto sense;
> + }
> +
> + if (!lu->attrs.thinprovisioning) {
> + key = ILLEGAL_REQUEST;
> + asc = ASC_INVALID_OP_CODE;
> + goto sense;
> + }
> +
> + if (lu->attrs.removable && !lu->attrs.online) {
> + key = NOT_READY;
> + asc = ASC_MEDIUM_NOT_PRESENT;
> + goto sense;
> + }
> +
> + if (lu->attrs.readonly) {
> + key = DATA_PROTECT;
> + asc = ASC_WRITE_PROTECT;
> + goto sense;
> + }
> +
> + ret = cmd->dev->bst->bs_cmd_submit(cmd);
> + if (ret) {
> + key = HARDWARE_ERROR;
> + asc = ASC_INTERNAL_TGT_FAILURE;
> + goto sense;
> + }
> +
> +sense:
> + cmd->offset = 0;
> + scsi_set_in_resid_by_actual(cmd, 0);
> + scsi_set_out_resid_by_actual(cmd, 0);
> +
> + sense_data_build(cmd, key, asc);
> + return SAM_STAT_CHECK_CONDITION;
> +}
> +
> static int sbc_rw(int host_no, struct scsi_cmd *cmd)
> {
> int ret;
> @@ -370,8 +424,11 @@ static int sbc_service_action(int host_no, struct scsi_cmd *cmd)
> data[2] = __cpu_to_be32(1UL << bshift);
>
> val = (cmd->dev->attrs.lbppbe << 16) | cmd->dev->attrs.la_lba;
> + if (cmd->dev->attrs.thinprovisioning)
> + val |= (3 << 14); /* set LBPME and LBPRZ */
> data[3] = __cpu_to_be32(val);
>
> +
> overflow:
> scsi_set_in_resid_by_actual(cmd, len);
> return SAM_STAT_GOOD;
> @@ -549,7 +606,24 @@ static struct device_type_template sbc_template = {
> {spc_illegal_op,},
> {spc_illegal_op,},
>
> - [0x40 ... 0x4f] = {spc_illegal_op,},
> + /* 0x40 */
> + {spc_illegal_op,},
> + {spc_illegal_op,},
> + {sbc_unmap,},
> + {spc_illegal_op,},
> + {spc_illegal_op,},
> + {spc_illegal_op,},
> + {spc_illegal_op,},
> + {spc_illegal_op,},
> +
> + {spc_illegal_op,},
> + {spc_illegal_op,},
> + {spc_illegal_op,},
> + {spc_illegal_op,},
> + {spc_illegal_op,},
> + {spc_illegal_op,},
> + {spc_illegal_op,},
> + {spc_illegal_op,},
>
> /* 0x50 */
> {spc_illegal_op,},
> diff --git a/usr/scsi.h b/usr/scsi.h
> index ca1109a..1508cc6 100644
> --- a/usr/scsi.h
> +++ b/usr/scsi.h
> @@ -60,6 +60,7 @@
> #define WRITE_LONG 0x3f
> #define CHANGE_DEFINITION 0x40
> #define WRITE_SAME 0x41
> +#define UNMAP 0x42
> #define READ_TOC 0x43
> #define LOG_SELECT 0x4c
> #define LOG_SENSE 0x4d
> diff --git a/usr/spc.c b/usr/spc.c
> index 44cd193..1834038 100644
> --- a/usr/spc.c
> +++ b/usr/spc.c
> @@ -139,6 +139,24 @@ static void update_vpd_83(struct scsi_lu *lu, void *id)
> strncpy((char *)data + 4, id, SCSI_ID_LEN);
> }
>
> +static void update_vpd_b2(struct scsi_lu *lu, void *id)
> +{
> + struct vpd *vpd_pg = lu->attrs.lu_vpd[PCODE_OFFSET(0xb2)];
> + uint8_t *data = vpd_pg->data;
> +
> + if (lu->attrs.thinprovisioning) {
> + data[0] = 0; /* threshold exponent */
> + data[1] = 0x84; /* LBPU LBPRZ */
> + data[2] = 0x02; /* provisioning type */
> + data[3] = 0;
> + } else {
> + data[0] = 0;
> + data[1] = 0;
> + data[2] = 0;
> + data[3] = 0;
> + }
> +}
> +
> static void update_b0_opt_xfer_gran(struct scsi_lu *lu, int opt_xfer_gran)
> {
> struct vpd *vpd_pg = lu->attrs.lu_vpd[PCODE_OFFSET(0xb0)];
> @@ -1661,7 +1679,7 @@ enum {
> Opt_removable, Opt_readonly, Opt_online,
> Opt_mode_page,
> Opt_path,
> - Opt_bsoflags,
> + Opt_bsoflags, Opt_thinprovisioning,
> Opt_err,
> };
>
> @@ -1682,6 +1700,7 @@ static match_table_t tokens = {
> {Opt_mode_page, "mode_page=%s"},
> {Opt_path, "path=%s"},
> {Opt_bsoflags, "bsoflags=%s"},
> + {Opt_thinprovisioning, "thin_provisioning=%s"},
> {Opt_err, NULL},
> };
>
> @@ -1772,6 +1791,12 @@ tgtadm_err lu_config(struct scsi_lu *lu, char *params, match_fn_t *fn)
> match_strncpy(buf, &args[0], sizeof(buf));
> attrs->readonly = atoi(buf);
> break;
> + case Opt_thinprovisioning:
> + match_strncpy(buf, &args[0], sizeof(buf));
> + attrs->thinprovisioning = atoi(buf);
> + /* update the provisioning vpd page */
> + lu_vpd[PCODE_OFFSET(0xb2)]->vpd_update(lu, NULL);
> + break;
> case Opt_online:
> match_strncpy(buf, &args[0], sizeof(buf));
> if (atoi(buf))
> @@ -1807,6 +1832,10 @@ int spc_lu_init(struct scsi_lu *lu)
>
> lu->attrs.device_type = lu->dev_type_template.type;
> lu->attrs.qualifier = 0x0;
> + lu->attrs.thinprovisioning = 0;
> + lu->attrs.removable = 0;
> + lu->attrs.readonly = 0;
> + lu->attrs.sense_format = 0;
>
> snprintf(lu->attrs.vendor_id, sizeof(lu->attrs.vendor_id),
> "%-16s", VENDOR_ID);
> @@ -1839,9 +1868,15 @@ int spc_lu_init(struct scsi_lu *lu)
> if (!lu_vpd[pg])
> return -ENOMEM;
>
> - lu->attrs.removable = 0;
> - lu->attrs.readonly = 0;
> - lu->attrs.sense_format = 0;
> + /* VPD page 0xb2 LOGICAL BLOCK PROVISIONING*/
> + pg = PCODE_OFFSET(0xb2);
> + lu_vpd[pg] = alloc_vpd(LBP_VPD_LEN);
> + if (!lu_vpd[pg])
> + return -ENOMEM;
> + lu_vpd[pg]->vpd_update = update_vpd_b2;
> + lu_vpd[pg]->vpd_update(lu, NULL);
> +
> +
> lu->dev_type_template.lu_offline(lu);
>
> return 0;
> diff --git a/usr/target.c b/usr/target.c
> index 0b6be13..dd3ca91 100644
> --- a/usr/target.c
> +++ b/usr/target.c
> @@ -1857,6 +1857,7 @@ tgtadm_err tgt_target_show_all(struct concat_buf *b)
> _TAB3 "Removable media: %s\n"
> _TAB3 "Prevent removal: %s\n"
> _TAB3 "Readonly: %s\n"
> + _TAB3 "Thin-provisioning: %s\n"
> _TAB3 "Backing store type: %s\n"
> _TAB3 "Backing store path: %s\n"
> _TAB3 "Backing store flags: %s\n",
> @@ -1871,6 +1872,7 @@ tgtadm_err tgt_target_show_all(struct concat_buf *b)
> lu_prevent_removal(lu) ?
> "Yes" : "No",
> lu->attrs.readonly ? "Yes" : "No",
> + lu->attrs.thinprovisioning ? "Yes" : "No",
> lu->bst ?
> (lu->bst->bs_name ? : "Unknown") :
> "None",
> diff --git a/usr/tgtd.h b/usr/tgtd.h
> index 726a3f5..03036ba 100644
> --- a/usr/tgtd.h
> +++ b/usr/tgtd.h
> @@ -14,6 +14,7 @@ struct concat_buf;
> #define PRODUCT_ID_LEN 16
> #define PRODUCT_REV_LEN 4
> #define BLOCK_LIMITS_VPD_LEN 0x3C
> +#define LBP_VPD_LEN 4
>
> #define PCODE_SHIFT 7
> #define PCODE_OFFSET(x) (x & ((1 << PCODE_SHIFT) - 1))
> @@ -72,6 +73,7 @@ struct lu_phy_attr {
> char qualifier; /* Peripheral Qualifier */
> char removable; /* Removable media */
> char readonly; /* Read-Only media */
> + char thinprovisioning; /* Use thin-provisioning for this LUN */
> char online; /* Logical Unit online */
> char sense_format; /* Descrptor format sense data supported */
> /* For the following see READ CAPACITY (16) */
> --
> 1.7.3.1
>
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