On Fri, Sep 06, 2024 at 10:58:47AM +0900, Damien Le Moal wrote: > The ncq_sense_buf buffer field of struct ata_port is allocated and used > only for devices that support the Command Duration Limits (CDL) feature. > However, the cdl buffer of struct ata_device, which is used to cache the > command duration limits log page for devices supporting CDL is always > allocated as part of struct ata_device, which is wasteful of memory for > devices that do not support this feature. > > Clean this up by defining both buffers as part of the new ata_cdl > structure and allocating this structure only for devices that support > the CDL feature. This new structure is attached to struct ata_device > using the cdl pointer. > > The functions ata_dev_init_cdl_resources() and > ata_dev_cleanup_cdl_resources() are defined to manage this new structure > allocation, initialization and freeing when a port is removed or a > device disabled. ata_dev_init_cdl_resources() is called from > ata_dev_config_cdl() only for devices that support CDL. > ata_dev_cleanup_cdl_resources() is called from ata_dev_free_resources() > to free the ata_cdl structure when a device is being disabled by EH. > > Note that the name of the former cdl log buffer of struct ata_device is > changed to desc_log_buf to make it clearer that it is a buffer for the > limit descriptors log page. > > This change reduces the size of struct ata_device, thus reducing memory > usage for ATA devices that do not support the CDL feature. > > Signed-off-by: Damien Le Moal <dlemoal@xxxxxxxxxx> > --- > drivers/ata/libata-core.c | 60 +++++++++++++++++++++++---------------- > drivers/ata/libata-sata.c | 2 +- > drivers/ata/libata-scsi.c | 2 +- > drivers/ata/libata.h | 1 + > include/linux/libata.h | 21 +++++++++++--- > 5 files changed, 56 insertions(+), 30 deletions(-) > > diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c > index bfd452b0d46d..bd2f8e442b14 100644 > --- a/drivers/ata/libata-core.c > +++ b/drivers/ata/libata-core.c > @@ -2464,12 +2464,40 @@ static void ata_dev_config_trusted(struct ata_device *dev) > dev->flags |= ATA_DFLAG_TRUSTED; > } > > +static int ata_dev_init_cdl_resources(struct ata_device *dev) > +{ > + struct ata_cdl *cdl = dev->cdl; > + unsigned int err_mask; > + > + if (!cdl) { > + cdl = kzalloc(sizeof(*cdl), GFP_KERNEL); > + if (!cdl) > + return -ENOMEM; > + dev->cdl = cdl; > + } > + > + err_mask = ata_read_log_page(dev, ATA_LOG_CDL, 0, cdl->desc_log_buf, > + ATA_LOG_CDL_SIZE / ATA_SECT_SIZE); > + if (err_mask) { > + ata_dev_warn(dev, "Read Command Duration Limits log failed\n"); > + return -EIO; Usually when a function return error, you expect it to have freed the resources that it might have allocated, so perhaps free and set dev->cdl to NULL here. > + } > + > + return 0; > +} > + > +void ata_dev_cleanup_cdl_resources(struct ata_device *dev) > +{ > + kfree(dev->cdl); > + dev->cdl = NULL; > +} > + > static void ata_dev_config_cdl(struct ata_device *dev) > { > - struct ata_port *ap = dev->link->ap; > unsigned int err_mask; > bool cdl_enabled; > u64 val; > + int ret; > > if (ata_id_major_version(dev->id) < 11) > goto not_supported; > @@ -2564,37 +2592,20 @@ static void ata_dev_config_cdl(struct ata_device *dev) > } > } > > - /* > - * Allocate a buffer to handle reading the sense data for successful > - * NCQ Commands log page for commands using a CDL with one of the limit > - * policy set to 0xD (successful completion with sense data available > - * bit set). > - */ > - if (!ap->ncq_sense_buf) { > - ap->ncq_sense_buf = kmalloc(ATA_LOG_SENSE_NCQ_SIZE, GFP_KERNEL); > - if (!ap->ncq_sense_buf) > - goto not_supported; > - } > - > - /* > - * Command duration limits is supported: cache the CDL log page 18h > - * (command duration descriptors). > - */ > - err_mask = ata_read_log_page(dev, ATA_LOG_CDL, 0, dev->sector_buf, 1); > - if (err_mask) { > - ata_dev_warn(dev, "Read Command Duration Limits log failed\n"); > + /* CDL is supported: allocate and initialize needed resources. */ > + ret = ata_dev_init_cdl_resources(dev); > + if (ret) { > + ata_dev_warn(dev, "Initialize CDL resources failed\n"); > goto not_supported; > } > > - memcpy(dev->cdl, dev->sector_buf, ATA_LOG_CDL_SIZE); > dev->flags |= ATA_DFLAG_CDL; > > return; > > not_supported: > dev->flags &= ~(ATA_DFLAG_CDL | ATA_DFLAG_CDL_ENABLED); > - kfree(ap->ncq_sense_buf); > - ap->ncq_sense_buf = NULL; > + ata_dev_cleanup_cdl_resources(dev); Considering that you now do ata_dev_init_cdl_resources() at the end, if you implement my suggestion above, we can remove the call to ata_dev_cleanup_cdl_resources() here, since we will only jump here if the ata_dev_init_cdl_resources() call failed. Either way: Reviewed-by: Niklas Cassel <cassel@xxxxxxxxxx> > } > > static int ata_dev_config_lba(struct ata_device *dev)