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Diffstat (limited to 'Documentation/filesystems/sysfs.rst')
| -rw-r--r-- | Documentation/filesystems/sysfs.rst | 27 |
1 files changed, 20 insertions, 7 deletions
diff --git a/Documentation/filesystems/sysfs.rst b/Documentation/filesystems/sysfs.rst index c32993bc83c7..2703c04af7d0 100644 --- a/Documentation/filesystems/sysfs.rst +++ b/Documentation/filesystems/sysfs.rst @@ -243,8 +243,8 @@ Other notes: - show() methods should return the number of bytes printed into the buffer. -- show() should only use sysfs_emit() or sysfs_emit_at() when formatting - the value to be returned to user space. +- New implementations of show() methods should only use sysfs_emit() or + sysfs_emit_at() when formatting the value to be returned to user space. - store() should return the number of bytes used from the buffer. If the entire buffer has been used, just return the count argument. @@ -299,7 +299,6 @@ The top level sysfs directory looks like:: hypervisor/ kernel/ module/ - net/ power/ devices/ contains a filesystem representation of the device tree. It maps @@ -313,7 +312,7 @@ kernel. Each bus's directory contains two subdirectories:: drivers/ devices/ contains symlinks for each device discovered in the system -that point to the device's directory under root/. +that point to the device's directory under /sys/devices. drivers/ contains a directory for each device driver that is loaded for devices on that particular bus (this assumes that drivers do not @@ -321,22 +320,36 @@ span multiple bus types). fs/ contains a directory for some filesystems. Currently each filesystem wanting to export attributes must create its own hierarchy -below fs/ (see ./fuse.rst for an example). +below fs/ (see fuse/fuse.rst for an example). module/ contains parameter values and state information for all loaded system modules, for both builtin and loadable modules. dev/ contains two directories: char/ and block/. Inside these two directories there are symlinks named <major>:<minor>. These symlinks -point to the sysfs directory for the given device. /sys/dev provides a +point to the directories under /sys/devices for each device. /sys/dev provides a quick way to lookup the sysfs interface for a device from the result of a stat(2) operation. More information on driver-model specific features can be found in Documentation/driver-api/driver-model/. +block/ contains symlinks to all the block devices discovered on the system. +These symlinks point to directories under /sys/devices. -TODO: Finish this section. +class/ contains a directory for each device class, grouped by functional type. +Each directory in class/ contains symlinks to devices in the /sys/devices directory. + +firmware/ contains system firmware data and configuration such as firmware tables, +ACPI information, and device tree data. + +hypervisor/ contains virtualization platform information and provides an interface to +the underlying hypervisor. It is only present when running on a virtual machine. + +kernel/ contains runtime kernel parameters, configuration settings, and status. + +power/ contains power management subsystem information including +sleep states, suspend/resume capabilities, and policies. Current Interfaces |