METHOD AND SYSTEM FOR ACCESSING DATA OBJECTS STORED IN A STORAGE SYSTEM USING OBJECT DESCRIPTORS ALLOCATED BY CLIENTS

• US 20170185327A1
• Filed: 12/29/2015
• Published: 06/29/2017
• Est. Priority Date: 12/29/2015
• Status: Active Grant

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: EMC Corporation (Dell Technologies Inc.)
• Inventors: Powell, David
• Granted Patent: US 10,852,955 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 3/0604 Improving or facilitating administration, e.g. storage management
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/0659 Command handling arrangements, e.g. command buffers, queues, command scheduling
• CPC Class Codes: G06F 3/0665 at area level, e.g. provisioning of virtual or logical volumes
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD

Abstract

A storage system includes a communication fabric, a storage module, a client device having an object descriptor (OD) generator to generate object descriptors (ODs) to access data stored in storage devices of the storage module. The storage system further includes a first control module (CM) coupled to the client device and the storage module via the communication fabric to manage accesses of the storage module. The first CM is adapted to receive a request from client device to access a data object stored in the storage module, where the request includes an OD uniquely identifying the data object and created by the OD generator of the client device. In response, the first CM examines a first object descriptor table (ODT) associated with the first CM to determine whether the OD is valid, and if the OD is valid allows the storage module to service the request.

Claims

1. A storage system, comprising:

a communication fabric;

a storage module coupled to the communication fabric, the storage module having one or more storage devices for storing data;

a client device coupled to the communication fabric, the client having an object descriptor (OD) generator to generate a plurality of object descriptors (ODs) for a plurality of data access sessions to access data stored in the storage devices of the storage module; and

a first control module (CM) coupled to the client device and the storage module via the communication fabric to manage accesses of the storage module, wherein the first CM is adapted to

receive a request from client device to access a data object stored in the storage module, the request including an OD uniquely identifying the data object, wherein the OD is created by the OD generator of the client device,

in response to the request, the first CM examines a first object descriptor table (ODT) associated with the first CM to determine whether the OD is valid, and

in response to determining that the OD is valid, to allow the storage module to service the request.

2. The storage system of claim 1, further comprising a second CM coupled to the communication fabric, wherein the second CM is further coupled to the first CM via an inter-processor link, and wherein the second CM maintains a second ODT to enable the second CM to provide accesses to the storage module.

3. The storage system of claim 2, wherein the first CM is further adapted to

transmit a control signal to the second CM via the inter-processor link to allow the second CM to synchronize the second ODT with the first ODT,

receive a response from the second CM indicating that the second ODT has been synchronized with the first ODT, and

return a status of the request to the client device indicating whether the request has been serviced successfully.

4. The storage system of claim 2, wherein the request is a first request to initiate a first data access session for accessing a first data object, wherein in response to the first request, the first CM is adapted to

examine the first ODT to determine whether the first ODT includes an ODT entry that matches a first OD extracted from the first request, wherein the first OD was created by the client device, and

in response to determining that no matching ODT entry is found,

create a first ODT entry in the first ODT to store the first OD and an attribute of the first data object to be accessed,

transmit a first control signal to the second CM via the inter-processor link to allow the second CM to synchronize the second ODT with respect to the first ODT entry, and

return a first status to the client device, in response to receiving a first response to the first control signal from the second CM via the inter-processor link.

5. The storage system of claim 4, wherein in response to determining that a matching ODT entry is found, the first CM denies the first request without synchronizing with the second CM.

6. The storage system of claim 2, wherein the request is a second request to terminate a second data access session of accessing a second data object, wherein in response to the second request, the first CM is adapted to

examine the first ODT to determine whether the first ODT includes an ODT entry that matches a second OD extracted from the second request, wherein the second OD was created by the client device, and

in response to determining that a second ODT entry is found matching the second OD, remove the second ODT entry from the first ODT,

transmit a second control signal to the second CM via the inter-processor link to allow the second CM to synchronize the second ODT with respect to the removed second ODT entry, and

return a second status to the client device, in response to receiving a second response to the second control signal from the second CM via the inter-processor link.

7. The storage system of claim 6, wherein in response to determining that no matching ODT entry matching the second OD is found, the first CM denies the second request without synchronizing with the second CM.

8. The storage system of claim 1, wherein the communication fabric comprises a peripheral component interface express (PCIe) fabric.

9. A computer-implemented method for accessing data in a storage system, the method comprising:

receiving, by a first control module (CM), a request from a client device to access a data object stored in a storage module having one or more storage devices, the request including an object descriptor (OD) uniquely identifying the data object, wherein the OD is created by an OD generator of the client device, wherein the first CM is coupled to the client device and the storage module via a communication fabric to manage accesses to data stored in the storage module;

in response to the request, examining by the first CM a first object descriptor table (ODT) associated with the first CM to determine whether the OD is valid; and

in response to determining that the OD is valid, allowing the storage module to service the request.

10. The method of claim 9, wherein the first CM is coupled to a second CM via an inter-processor link, wherein the second CM is coupled to the client device and the storage module via the communication fabric, and wherein the second CM maintains a second ODT to enable the second CM to provide accesses to the storage module.

11. The method of claim 10, further comprising:

transmitting a control signal from the first CM to the second CM via the inter-processor link to allow the second CM to synchronize the second ODT with the first ODT,

receiving by the first CM a response from the second CM indicating that the second ODT has been synchronized with the first ODT, and

returning by the first CM a status of the request to the client device indicating whether the request has been serviced successfully.

12. The method of claim 10, wherein the request is a first request to initiate a first data access session for accessing a first data object, wherein the method further comprises:

examining the first ODT to determine whether the first ODT includes an ODT entry that matches a first OD extracted from the first request, wherein the first OD was created by the client device; and

in response to determining that no matching ODT entry is found,

creating a first ODT entry in the first ODT to store the first OD and an attribute of the first data object to be accessed,

transmitting a first control signal to the second CM via the inter-processor link to allow the second CM to synchronize the second ODT with respect to the first ODT entry, and

returning a first status to the client device, in response to receiving a first response to the first control signal from the second CM via the inter-processor link.

13. The method of claim 12, further comprising, in response to determining that a matching ODT entry is found, denying the first request without synchronizing with the second CM.

14. The method of claim 10, wherein the request is a second request to terminate a second data access session of accessing a second data object, wherein the method further comprises:

examining the first ODT to determine whether the first ODT includes an ODT entry that matches a second OD extracted from the second request, wherein the second OD was created by the client device; and

in response to determining that a second ODT entry is found matching the second OD, removing the second ODT entry from the first ODT,

transmitting a second control signal to the second CM via the inter-processor link to allow the second CM to synchronize the second ODT with respect to the removed second ODT entry, and

returning a second status to the client device, in response to receiving a second response to the second control signal from the second CM via the inter-processor link.

15. The method of claim 14, further comprising, in response to determining that no matching ODT entry matching the second OD is found, denying the second request without synchronizing with the second CM.

16. The method of claim 9, wherein the communication fabric comprises a peripheral component interface express (PCIe) fabric.

17. A non-transitory machine-readable medium having instructions stored therein, which when executed by a machine, cause the machine to perform operations of accessing data in a storage system, the operations comprising:

receiving, by a first control module (CM), a request from a client device to access a data object stored in a storage module having one or more storage devices, the request including an object descriptor (OD) uniquely identifying the data object, wherein the OD is created by an OD generator of the client device, wherein the first CM is coupled to the client device and the storage module via a communication fabric to manage accesses to data stored in the storage module;

in response to the request, examining by the first CM a first object descriptor table (ODT) associated with the first CM to determine whether the OD is valid; and

in response to determining that the OD is valid, allowing the storage module to service the request.

18. The non-transitory machine-readable medium of claim 17, wherein the first CM is coupled to a second CM via an inter-processor link, wherein the second CM is coupled to the client device and the storage module via the communication fabric, and wherein the second CM maintains a second ODT to enable the second CM to provide accesses to the storage module.

19. The non-transitory machine-readable medium of claim 18, wherein the operations further comprise:

transmitting a control signal from the first CM to the second CM via the inter-processor link to allow the second CM to synchronize the second ODT with the first ODT,

receiving by the first CM a response from the second CM indicating that the second ODT has been synchronized with the first ODT, and

returning by the first CM a status of the request to the client device indicating whether the request has been serviced successfully.

20. The non-transitory machine-readable medium of claim 18, wherein the request is a first request to initiate a first data access session for accessing a first data object, wherein the method further comprises:

examining the first ODT to determine whether the first ODT includes an ODT entry that matches a first OD extracted from the first request, wherein the first OD was created by the client device; and

in response to determining that no matching ODT entry is found,

creating a first ODT entry in the first ODT to store the first OD and an attribute of the first data object to be accessed,

transmitting a first control signal to the second CM via the inter-processor link to allow the second CM to synchronize the second ODT with respect to the first ODT entry, and

returning a first status to the client device, in response to receiving a first response to the first control signal from the second CM via the inter-processor link.

21. The non-transitory machine-readable medium of claim 20, wherein the operations further comprise, in response to determining that a matching ODT entry is found, denying the first request without synchronizing with the second CM.

22. The non-transitory machine-readable medium of claim 18, wherein the request is a second request to terminate a second data access session of accessing a second data object, wherein the method further comprises:

examining the first ODT to determine whether the first ODT includes an ODT entry that matches a second OD extracted from the second request, wherein the second OD was created by the client device; and

in response to determining that a second ODT entry is found matching the second OD, removing the second ODT entry from the first ODT,

transmitting a second control signal to the second CM via the inter-processor link to allow the second CM to synchronize the second ODT with respect to the removed second ODT entry, and

returning a second status to the client device, in response to receiving a second response to the second control signal from the second CM via the inter-processor link.

23. The non-transitory machine-readable medium of claim 22, wherein the operations further comprise, in response to determining that no matching ODT entry matching the second OD is found, denying the second request without synchronizing with the second CM.

24. The non-transitory machine-readable medium of claim 17, wherein the communication fabric comprises a peripheral component interface express (PCIe) fabric.