Memory system and method for controlling nonvolatile memory
According to one embodiment, when receiving a write request to designate a first block number and a first logical address from a host, a memory system determines a first location in a first block having the first block number, to which data from the host is to be written, and writes the data from the host to the first location of the first block. The memory system updates a first address translation table managing mapping between logical addresses and in-block physical addresses of the first block, and maps a first in-block physical address indicative of the first location to the first logical address.
1. A memory system connectable to a host, comprising:
a nonvolatile memory including a plurality of blocks each including a plurality of pages; and
a controller electrically connected to the nonvolatile memory, the controller being configured to,
in response to receiving a write request from the host, the write request designating a first block number and a first logical address,
determine a first location in a first block corresponding to the first block number,
write data to the first location in the first block, the data being associated with the first logical address, and
update a first table such that a first in-block physical address corresponding to the first location is mapped to the first logical address, the first table mapping between logical addresses and in-block physical addresses of the first block but not mapping between the logical addresses and a physical address of the first block.
2. The memory system of claim 1 , wherein the controller is further configured to,
in response to receiving a read request from the host, the read request designating the first block number and the first logical address,
acquire the first in-block physical address by referring to the first table, and
read data associated with the first logical address from the nonvolatile memory, based on the first block number and the acquired first in-block physical address.
3. The memory system of claim 1 , wherein the first in-block physical address is represented by a first in-block offset indicating an offset from a leading part of the first block to the first location by a multiple of a grain having a size different from a page size.
4. The memory system of claim 1 , wherein the controller is further configured to,
in response to receiving a control command from the host, the control command designating a copy source block number and a copy destination block number,
select a second block corresponding to the copy source block number and a third block corresponding to the copy destination block number, of the plurality of blocks, and
copy valid data from a copy source location in the second block to a copy destination location in the third block.
5. The memory system of claim 4 , wherein the controller is further configured to
update a second table mapping between logical addresses and in-block physical addresses of the second block, and a third table mapping between logical addresses and in-block physical addresses of the third block, such that an in-block physical address mapped to a logical address of the valid data is changed from a second in-block physical address indicative of the copy source location in the second block to a third in-block physical address indicative of the copy destination location of the third block.
6. The memory system of claim 5 , wherein the second in-block physical address is represented by a second in-block offset indicating an offset from a leading part of the second block to the copy source location by a multiple of a grain, and the third in-block physical address is represented by a third in-block offset indicating an offset from a leading part of the third block to the copy destination location by a multiple of the grain, the grain having a size different from a page size.
7. The memory system of claim 4 , wherein the controller is further configured to
notify the host of a logical address of the valid data and the copy destination block number to which the valid data is copied.
8. The memory system of claim 1 , wherein the controller is further configured to,
in response to receiving a first command from the host, the first command requesting to report a maximum block number to the host,
notify the host of the maximum block number indicative of the number of the plurality of blocks, and
in response to receiving a second command from the host, the second command requesting to report a block size to the host,
notify the host of the block size of each of the plurality of blocks.
9. The memory system of claim 8 , wherein the controller is further configured to,
if a block number is included in the second command,
notify the host of a block size of a block corresponding to the block number included in the second command.