[PATCH v5 10/16] lpfc: vmid: Functions to manage vmids

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: Gaurav Srivastava <gaurav.srivastava@xxxxxxxxxxxx>

This patch contains the routines to save, retrieve and remove the vmids
from the data structure. A hash table is used to save the vmids and
the corresponding UUIDs associated with the application/VMs.

Signed-off-by: Gaurav Srivastava  <gaurav.srivastava@xxxxxxxxxxxx>
Signed-off-by: James Smart <jsmart2021@xxxxxxxxx>

---
v5:
Changed Return code to non-numeric/Symbol

v4:
No change

v3:
No change

v2:
Ported the patch on top of 5.10/scsi-queue
---
 drivers/scsi/lpfc/lpfc_scsi.c | 139 ++++++++++++++++++++++++++++++++++
 1 file changed, 139 insertions(+)

diff --git a/drivers/scsi/lpfc/lpfc_scsi.c b/drivers/scsi/lpfc/lpfc_scsi.c
index b79b6f03cdb6..6a6a9a314368 100644
--- a/drivers/scsi/lpfc/lpfc_scsi.c
+++ b/drivers/scsi/lpfc/lpfc_scsi.c
@@ -28,6 +28,7 @@
 #include <asm/unaligned.h>
 #include <linux/t10-pi.h>
 #include <linux/crc-t10dif.h>
+#include <linux/blk-cgroup.h>
 #include <net/checksum.h>
 
 #include <scsi/scsi.h>
@@ -5131,6 +5132,144 @@ void lpfc_poll_timeout(struct timer_list *t)
 	}
 }
 
+/*
+ * lpfc_get_vmid_from_hastable - search the UUID in the hash table
+ * @vport: The virtual port for which this call is being executed.
+ * @hash: calculated hash value
+ * @buf: uuid associated with the VE
+ * Returns the vmid entry associated with the UUID
+ * Make sure to acquire the appropriate lock before invoking this routine.
+ */
+struct lpfc_vmid *lpfc_get_vmid_from_hastable(struct lpfc_vport *vport,
+					      u32 hash, u8 *buf)
+{
+	struct lpfc_vmid *vmp;
+	u16 count = 0;
+
+	while (count < LPFC_VMID_HASH_SIZE) {
+		vmp = vport->hash_table[hash];
+		if (vmp) {
+			if (strncmp(&vmp->host_vmid[0], buf, 16) == 0)
+				return vmp;
+		} else {
+			return NULL;
+		}
+		/* search the next available slot and continue till entry */
+		/* is found */
+		count++;
+		hash++;
+
+		/* or the end is reached */
+		if (hash == LPFC_VMID_HASH_SIZE)
+			hash = 0;
+	}
+	return NULL;
+}
+
+/*
+ * lpfc_put_vmid_from_hastable - put the VMID in the hash table
+ * @vport: The virtual port for which this call is being executed.
+ * @hash - calculated hash value
+ * @vmp: Pointer to a VMID entry representing a VM sending IO
+ *
+ * This routine will insert the newly acquired vmid entity in the hash table.
+ * Make sure to acquire the appropriate lock before invoking this routine.
+ */
+int
+lpfc_put_vmid_in_hashtable(struct lpfc_vport *vport, u32 hash,
+			   struct lpfc_vmid *vmp)
+{
+	int count = 0;
+
+	while (count < LPFC_VMID_HASH_SIZE) {
+		if (!vport->hash_table[hash]) {
+			vport->hash_table[hash] = vmp;
+			vmp->hash_index = hash;
+			return FAILURE;
+		}
+		/* if the slot is already occupied, a collision has occurred. */
+		/* Store in the next available slot */
+		count++;
+		hash++;
+		/* table is full */
+		if (hash == LPFC_VMID_HASH_SIZE)
+			hash = 0;
+	}
+	return 0;
+}
+
+/*
+ * lpfc_vmid_hash_fn- creates a hash value of the UUID
+ * @uuid: uuid associated with the VE
+ * @len: length of the UUID
+ * Returns the calculated hash value
+ */
+int lpfc_vmid_hash_fn(char *vmid, int len)
+{
+	int c;
+	int hash = 0;
+
+	if (len == 0)
+		return 0;
+	while (len--) {
+		c = *vmid++;
+		if (c >= 'A' && c <= 'Z')
+			c += 'a' - 'A';
+
+		hash = (hash + (c << LPFC_VMID_HASH_SHIFT) +
+			(c >> LPFC_VMID_HASH_SHIFT)) * 19;
+	}
+
+	return hash & LPFC_VMID_HASH_MASK;
+}
+
+/*
+ * lpfc_vmid_update_entry - update the vmid entry in the hash table
+ * @vport: The virtual port for which this call is being executed.
+ * @cmd: address of scsi cmmd descriptor
+ * @vmp: Pointer to a VMID entry representing a VM sending IO
+ * @tag: VMID tag
+ */
+void lpfc_vmid_update_entry(struct lpfc_vport *vport, struct scsi_cmnd
+				   *cmd, struct lpfc_vmid *vmp,
+				   union lpfc_vmid_io_tag *tag)
+{
+	u64 *lta;
+
+	if (vport->vmid_priority_tagging)
+		tag->cs_ctl_vmid = vmp->un.cs_ctl_vmid;
+	else
+		tag->app_id = vmp->un.app_id;
+
+	if (cmd->sc_data_direction == DMA_TO_DEVICE)
+		vmp->io_wr_cnt++;
+	else
+		vmp->io_rd_cnt++;
+
+	/* update the last access timestamp in the table */
+	lta = per_cpu_ptr(vmp->last_io_time, raw_smp_processor_id());
+	*lta = jiffies;
+}
+
+void lpfc_vmid_assign_cs_ctl(struct lpfc_vport *vport, struct lpfc_vmid *vmid)
+{
+	u32 hash;
+	struct lpfc_vmid *pvmid;
+
+	if (vport->port_type == LPFC_PHYSICAL_PORT) {
+		vmid->un.cs_ctl_vmid = lpfc_vmid_get_cs_ctl(vport);
+	} else {
+		hash = lpfc_vmid_hash_fn(vmid->host_vmid, vmid->vmid_len);
+		pvmid =
+		    lpfc_get_vmid_from_hastable(vport->phba->pport, hash,
+						vmid->host_vmid);
+		if (!pvmid)
+			vmid->un.cs_ctl_vmid = pvmid->un.cs_ctl_vmid;
+		else
+			vmid->un.cs_ctl_vmid = lpfc_vmid_get_cs_ctl(vport);
+	}
+}
+
 /**
  * lpfc_queuecommand - scsi_host_template queuecommand entry point
  * @shost: kernel scsi host pointer.
-- 
2.26.2


-- 
This electronic communication and the information and any files transmitted 
with it, or attached to it, are confidential and are intended solely for 
the use of the individual or entity to whom it is addressed and may contain 
information that is confidential, legally privileged, protected by privacy 
laws, or otherwise restricted from disclosure to anyone else. If you are 
not the intended recipient or the person responsible for delivering the 
e-mail to the intended recipient, you are hereby notified that any use, 
copying, distributing, dissemination, forwarding, printing, or copying of 
this e-mail is strictly prohibited. If you received this e-mail in error, 
please return the e-mail to the sender, delete it from your computer, and 
destroy any printed copy of it.

Attachment: smime.p7s
Description: S/MIME Cryptographic Signature


[Index of Archives]     [Linux RAID]     [Linux SCSI]     [Linux ATA RAID]     [IDE]     [Linux Wireless]     [Linux Kernel]     [ATH6KL]     [Linux Bluetooth]     [Linux Netdev]     [Kernel Newbies]     [Security]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Device Mapper]

  Powered by Linux