Re: [PATCH 1/3] libata: Whitelist SSDs that are known to properly return zeroes after TRIM

2014-12-08 Thread Theodore Ts'o
On Fri, Dec 05, 2014 at 10:58:09PM +, Elliott, Robert (Server Storage) wrote: I have a Crucial_CT256MX1 (i.e. MX100) and it does reliably zero. make me concerned about this whitelist approach. I think you need a manufacturer assertion that this is indeed the design intent; you cannot

Re: [PATCH 1/3] libata: Whitelist SSDs that are known to properly return zeroes after TRIM

2014-12-08 Thread James Bottomley
On Mon, 2014-12-08 at 10:15 -0500, Theodore Ts'o wrote: On Fri, Dec 05, 2014 at 10:58:09PM +, Elliott, Robert (Server Storage) wrote: I have a Crucial_CT256MX1 (i.e. MX100) and it does reliably zero. make me concerned about this whitelist approach. I think you need a

Re: [PATCH 1/3] libata: Whitelist SSDs that are known to properly return zeroes after TRIM

2014-12-08 Thread One Thousand Gnomes
On Mon, 8 Dec 2014 10:15:59 -0500 Theodore Ts'o ty...@mit.edu wrote: On Fri, Dec 05, 2014 at 10:58:09PM +, Elliott, Robert (Server Storage) wrote: I have a Crucial_CT256MX1 (i.e. MX100) and it does reliably zero. make me concerned about this whitelist approach. I think you

Re: [PATCH 1/3] libata: Whitelist SSDs that are known to properly return zeroes after TRIM

2014-12-05 Thread Paolo Bonzini
On 07/11/2014 06:08, Martin K. Petersen wrote: The whitelist is only meant as a starting point and is by no means comprehensive: - All intel SSD models except for 510 - Micron M5* - Samsung SSDs - Seagate SSDs Signed-off-by: Martin K. Petersen martin.peter...@oracle.com

RE: [PATCH 1/3] libata: Whitelist SSDs that are known to properly return zeroes after TRIM

2014-12-05 Thread Elliott, Robert (Server Storage)
Cc: Martin K. Petersen Subject: [PATCH 1/3] libata: Whitelist SSDs that are known to properly return zeroes after TRIM As defined, the DRAT (Deterministic Read After Trim) and RZAT (Return Zero After Trim) flags in the ATA Command Set are unreliable in the sense that they only define what

Re: [PATCH 1/3] libata: Whitelist SSDs that are known to properly return zeroes after TRIM

2014-11-07 Thread Christoph Hellwig
On Fri, Nov 07, 2014 at 12:08:12AM -0500, Martin K. Petersen wrote: if (ata_id_has_trim(args-id)) { - rbuf[14] |= 0x80; /* TPE */ + rbuf[14] |= 0x80; /* LBPME */ - if (ata_id_has_zero_after_trim(args-id)) -

Re: [PATCH 1/3] libata: Whitelist SSDs that are known to properly return zeroes after TRIM

2014-11-07 Thread Martin K. Petersen
Christoph == Christoph Hellwig h...@infradead.org writes: + ata_dev_warn(dev, Enabling discard_zeroes_data\n); Christoph I think this should _info, not _warn. Fixed. -- Martin K. Petersen Oracle Linux Engineering -- To unsubscribe from this list: send the line unsubscribe linux-scsi in

[PATCH 1/3] libata: Whitelist SSDs that are known to properly return zeroes after TRIM

2014-11-06 Thread Martin K. Petersen
As defined, the DRAT (Deterministic Read After Trim) and RZAT (Return Zero After Trim) flags in the ATA Command Set are unreliable in the sense that they only define what happens if the device successfully executed the DSM TRIM command. TRIM is only advisory, however, and the device is free to