From 72fa4b742b327bd1b07985d79a61c61dbd9fd4e6 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 31 May 2006 18:27:32 +0900 Subject: [PATCH] libata-hp-prep: make some ata_device fields persistent Lifetimes of some fields span over device plugging/unplugging. This patch moves such persistent fields to the top of ata_device and separate them with ATA_DEVICE_CLEAR_OFFSET. Fields above the offset are initialized once during host initializatino while all other fields are cleared before hotplugging. Currently ->ap, devno and part of flags are persistent. Note that flags is partially cleared while holding host_set lock. This is to synchronize with later warm plug implementation which will record hotplug request in dev->flags. Signed-off-by: Tejun Heo --- include/linux/libata.h | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/libata.h b/include/linux/libata.h index d4a668c..aa14eda 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -130,6 +130,7 @@ enum { ATA_DFLAG_CFG_MASK = (1 << 8) - 1, ATA_DFLAG_PIO = (1 << 8), /* device currently in PIO mode */ + ATA_DFLAG_INIT_MASK = (1 << 16) - 1, ATA_DFLAG_DETACH = (1 << 16), ATA_DFLAG_DETACHED = (1 << 17), @@ -410,10 +411,11 @@ struct ata_ering { struct ata_device { struct ata_port *ap; - u64 n_sectors; /* size of device, if ATA */ + unsigned int devno; /* 0 or 1 */ unsigned long flags; /* ATA_DFLAG_xxx */ + /* n_sector is used as CLEAR_OFFSET, read comment above CLEAR_OFFSET */ + u64 n_sectors; /* size of device, if ATA */ unsigned int class; /* ATA_DEV_xxx */ - unsigned int devno; /* 0 or 1 */ u16 id[ATA_ID_WORDS]; /* IDENTIFY xxx DEVICE data */ u8 pio_mode; u8 dma_mode; @@ -439,6 +441,11 @@ struct ata_device { struct ata_ering ering; }; +/* Offset into struct ata_device. Fields above it are maintained + * acress device init. Fields below are zeroed. + */ +#define ATA_DEVICE_CLEAR_OFFSET offsetof(struct ata_device, n_sectors) + struct ata_eh_info { struct ata_device *dev; /* offending device */ u32 serror; /* SError from LLDD */ -- cgit v1.1