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Chapter 2. The /proc File System
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------------- drive0 --------- drive1 -------- drive0 ---------- drive1 -----DMA enabled:
UDMA enabled:
UDMA enabled:
UDMA
DMA
PIO
yes
yes
2
no
no
X
yes
no
X
no
no
X
Navigating into the directory for an IDE channel, such as ide0, provides additional information. The
channel file provides the channel number, while the model tells you the bus type for the channel
(such as pci).
2.3.4.1. The Device Directory
Within each IDE channel directory is a device directory. The name of the device directory corresponds
to the drive letter in the /dev directory. For instance the first IDE drive on ide0 would be hda.
Note
There is a symlink to each of these device directories in the /proc/ide/ directory.
Each device directory contains a collection of information and statistics. The contents of these directories vary according to the type of device connected. Some of the more useful files common to many
devices include:
• cache
— The device’s cache.
• capacity
• driver
— The capacity of the device, in 512 byte blocks.
— The driver and version used to control the device.
• geometry
— The physical and logical geometry of the device.
• media
— The type of device, such as a disk.
• model
— The model name or number of the device.
— A collection of current parameters of the device. This file usually contains quite a
bit of useful, technical information. A sample settings file for a standard IDE hard disk looks
similar to this:
• settings
name
---bios_cyl
bios_head
bios_sect
breada_readahead
bswap
current_speed
file_readahead
ide_scsi
init_speed
io_32bit
keepsettings
lun
max_kb_per_request
multcount
nice1
value
----784
255
63
4
0
66
0
0
66
0
0
0
64
8
1
min
--0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
max
--65535
255
63
127
1
69
2097151
1
69
3
1
7
127
8
1
mode
---rw
rw
rw
rw
r
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw