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authorLinus Torvalds <torvalds@linux-foundation.org>2016-01-13 19:37:36 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2016-01-13 19:37:36 -0800
commit1289ace5b4f70f1e68ce785735b82c7e483de863 (patch)
treef616d22bb51c50f79daff2632b7960c46afb5168 /drivers/scsi/scsi_lib.c
parentd080827f850ba4df5b955d5ca8c8c0fc92fe18c0 (diff)
parentabaee091a18c19ccd86feb1c8374585d82e96777 (diff)
Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull first round of SCSI updates from James Bottomley: "This includes driver updates from the usual suspects (bfa, arcmsr, scsi_dh_alua, lpfc, storvsc, cxlflash). The major change is the addition of the hisi_sas driver, which is an ARM platform device for SAS. The other change of note is an enormous style transformation to the atp870u driver (which is our worst written SCSI driver)" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (169 commits) cxlflash: Enable device id for future IBM CXL adapter cxlflash: Resolve oops in wait_port_offline cxlflash: Fix to resolve cmd leak after host reset cxlflash: Removed driver date print cxlflash: Fix to avoid virtual LUN failover failure cxlflash: Fix to escalate LINK_RESET also on port 1 storvsc: Tighten up the interrupt path storvsc: Refactor the code in storvsc_channel_init() storvsc: Properly support Fibre Channel devices storvsc: Fix a bug in the layout of the hv_fc_wwn_packet mvsas: Add SGPIO support to Marvell 94xx mpt3sas: A correction in unmap_resources hpsa: Add box and bay information for enclosure devices hpsa: Change SAS transport devices to bus 0. hpsa: fix path_info_show cciss: print max outstanding commands as a hex value scsi_debug: Increase the reported optimal transfer length lpfc: Update version to 11.0.0.10 for upstream patch set lpfc: Use kzalloc instead of kmalloc lpfc: Delete unnecessary checks before the function call "mempool_destroy" ...
Diffstat (limited to 'drivers/scsi/scsi_lib.c')
-rw-r--r--drivers/scsi/scsi_lib.c188
1 files changed, 188 insertions, 0 deletions
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index dd8ad2a44510..fa6b2c4eb7a2 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -23,6 +23,7 @@
#include <linux/scatterlist.h>
#include <linux/blk-mq.h>
#include <linux/ratelimit.h>
+#include <asm/unaligned.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
@@ -3154,3 +3155,190 @@ void sdev_enable_disk_events(struct scsi_device *sdev)
atomic_dec(&sdev->disk_events_disable_depth);
}
EXPORT_SYMBOL(sdev_enable_disk_events);
+
+/**
+ * scsi_vpd_lun_id - return a unique device identification
+ * @sdev: SCSI device
+ * @id: buffer for the identification
+ * @id_len: length of the buffer
+ *
+ * Copies a unique device identification into @id based
+ * on the information in the VPD page 0x83 of the device.
+ * The string will be formatted as a SCSI name string.
+ *
+ * Returns the length of the identification or error on failure.
+ * If the identifier is longer than the supplied buffer the actual
+ * identifier length is returned and the buffer is not zero-padded.
+ */
+int scsi_vpd_lun_id(struct scsi_device *sdev, char *id, size_t id_len)
+{
+ u8 cur_id_type = 0xff;
+ u8 cur_id_size = 0;
+ unsigned char *d, *cur_id_str;
+ unsigned char __rcu *vpd_pg83;
+ int id_size = -EINVAL;
+
+ rcu_read_lock();
+ vpd_pg83 = rcu_dereference(sdev->vpd_pg83);
+ if (!vpd_pg83) {
+ rcu_read_unlock();
+ return -ENXIO;
+ }
+
+ /*
+ * Look for the correct descriptor.
+ * Order of preference for lun descriptor:
+ * - SCSI name string
+ * - NAA IEEE Registered Extended
+ * - EUI-64 based 16-byte
+ * - EUI-64 based 12-byte
+ * - NAA IEEE Registered
+ * - NAA IEEE Extended
+ * as longer descriptors reduce the likelyhood
+ * of identification clashes.
+ */
+
+ /* The id string must be at least 20 bytes + terminating NULL byte */
+ if (id_len < 21) {
+ rcu_read_unlock();
+ return -EINVAL;
+ }
+
+ memset(id, 0, id_len);
+ d = vpd_pg83 + 4;
+ while (d < vpd_pg83 + sdev->vpd_pg83_len) {
+ /* Skip designators not referring to the LUN */
+ if ((d[1] & 0x30) != 0x00)
+ goto next_desig;
+
+ switch (d[1] & 0xf) {
+ case 0x2:
+ /* EUI-64 */
+ if (cur_id_size > d[3])
+ break;
+ /* Prefer NAA IEEE Registered Extended */
+ if (cur_id_type == 0x3 &&
+ cur_id_size == d[3])
+ break;
+ cur_id_size = d[3];
+ cur_id_str = d + 4;
+ cur_id_type = d[1] & 0xf;
+ switch (cur_id_size) {
+ case 8:
+ id_size = snprintf(id, id_len,
+ "eui.%8phN",
+ cur_id_str);
+ break;
+ case 12:
+ id_size = snprintf(id, id_len,
+ "eui.%12phN",
+ cur_id_str);
+ break;
+ case 16:
+ id_size = snprintf(id, id_len,
+ "eui.%16phN",
+ cur_id_str);
+ break;
+ default:
+ cur_id_size = 0;
+ break;
+ }
+ break;
+ case 0x3:
+ /* NAA */
+ if (cur_id_size > d[3])
+ break;
+ cur_id_size = d[3];
+ cur_id_str = d + 4;
+ cur_id_type = d[1] & 0xf;
+ switch (cur_id_size) {
+ case 8:
+ id_size = snprintf(id, id_len,
+ "naa.%8phN",
+ cur_id_str);
+ break;
+ case 16:
+ id_size = snprintf(id, id_len,
+ "naa.%16phN",
+ cur_id_str);
+ break;
+ default:
+ cur_id_size = 0;
+ break;
+ }
+ break;
+ case 0x8:
+ /* SCSI name string */
+ if (cur_id_size + 4 > d[3])
+ break;
+ /* Prefer others for truncated descriptor */
+ if (cur_id_size && d[3] > id_len)
+ break;
+ cur_id_size = id_size = d[3];
+ cur_id_str = d + 4;
+ cur_id_type = d[1] & 0xf;
+ if (cur_id_size >= id_len)
+ cur_id_size = id_len - 1;
+ memcpy(id, cur_id_str, cur_id_size);
+ /* Decrease priority for truncated descriptor */
+ if (cur_id_size != id_size)
+ cur_id_size = 6;
+ break;
+ default:
+ break;
+ }
+next_desig:
+ d += d[3] + 4;
+ }
+ rcu_read_unlock();
+
+ return id_size;
+}
+EXPORT_SYMBOL(scsi_vpd_lun_id);
+
+/*
+ * scsi_vpd_tpg_id - return a target port group identifier
+ * @sdev: SCSI device
+ *
+ * Returns the Target Port Group identifier from the information
+ * froom VPD page 0x83 of the device.
+ *
+ * Returns the identifier or error on failure.
+ */
+int scsi_vpd_tpg_id(struct scsi_device *sdev, int *rel_id)
+{
+ unsigned char *d;
+ unsigned char __rcu *vpd_pg83;
+ int group_id = -EAGAIN, rel_port = -1;
+
+ rcu_read_lock();
+ vpd_pg83 = rcu_dereference(sdev->vpd_pg83);
+ if (!vpd_pg83) {
+ rcu_read_unlock();
+ return -ENXIO;
+ }
+
+ d = sdev->vpd_pg83 + 4;
+ while (d < sdev->vpd_pg83 + sdev->vpd_pg83_len) {
+ switch (d[1] & 0xf) {
+ case 0x4:
+ /* Relative target port */
+ rel_port = get_unaligned_be16(&d[6]);
+ break;
+ case 0x5:
+ /* Target port group */
+ group_id = get_unaligned_be16(&d[6]);
+ break;
+ default:
+ break;
+ }
+ d += d[3] + 4;
+ }
+ rcu_read_unlock();
+
+ if (group_id >= 0 && rel_id && rel_port != -1)
+ *rel_id = rel_port;
+
+ return group_id;
+}
+EXPORT_SYMBOL(scsi_vpd_tpg_id);