Loading Documentation/ABI/testing/sysfs-fs-f2fs +56 −0 Original line number Diff line number Diff line Loading @@ -74,3 +74,59 @@ Date: March 2014 Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com> Description: Controls the memory footprint used by f2fs. What: /sys/fs/f2fs/<disk>/trim_sections Date: February 2015 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> Description: Controls the trimming rate in batch mode. What: /sys/fs/f2fs/<disk>/cp_interval Date: October 2015 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> Description: Controls the checkpoint timing. What: /sys/fs/f2fs/<disk>/idle_interval Date: January 2016 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> Description: Controls the idle timing. What: /sys/fs/f2fs/<disk>/ra_nid_pages Date: October 2015 Contact: "Chao Yu" <chao2.yu@samsung.com> Description: Controls the count of nid pages to be readaheaded. What: /sys/fs/f2fs/<disk>/dirty_nats_ratio Date: January 2016 Contact: "Chao Yu" <chao2.yu@samsung.com> Description: Controls dirty nat entries ratio threshold, if current ratio exceeds configured threshold, checkpoint will be triggered for flushing dirty nat entries. What: /sys/fs/f2fs/<disk>/lifetime_write_kbytes Date: January 2016 Contact: "Shuoran Liu" <liushuoran@huawei.com> Description: Shows total written kbytes issued to disk. What: /sys/fs/f2fs/<disk>/inject_rate Date: May 2016 Contact: "Sheng Yong" <shengyong1@huawei.com> Description: Controls the injection rate. What: /sys/fs/f2fs/<disk>/inject_type Date: May 2016 Contact: "Sheng Yong" <shengyong1@huawei.com> Description: Controls the injection type. What: /sys/fs/f2fs/<disk>/reserved_blocks Date: June 2017 Contact: "Chao Yu" <yuchao0@huawei.com> Description: Controls current reserved blocks in system. Documentation/Makefile +1 −1 Original line number Diff line number Diff line subdir-y := accounting auxdisplay blackfin connector \ filesystems filesystems ia64 laptops mic misc-devices \ filesystems filesystems ia64 laptops misc-devices \ networking pcmcia prctl ptp spi timers vDSO video4linux \ watchdog Documentation/arm64/tagged-pointers.txt +47 −15 Original line number Diff line number Diff line Loading @@ -11,24 +11,56 @@ in AArch64 Linux. The kernel configures the translation tables so that translations made via TTBR0 (i.e. userspace mappings) have the top byte (bits 63:56) of the virtual address ignored by the translation hardware. This frees up this byte for application use, with the following caveats: this byte for application use. (1) The kernel requires that all user addresses passed to EL1 are tagged with tag 0x00. This means that any syscall parameters containing user virtual addresses *must* have their top byte cleared before trapping to the kernel. (2) Non-zero tags are not preserved when delivering signals. This means that signal handlers in applications making use of tags cannot rely on the tag information for user virtual addresses being maintained for fields inside siginfo_t. One exception to this rule is for signals raised in response to watchpoint debug exceptions, where the tag information will be preserved. Passing tagged addresses to the kernel -------------------------------------- (3) Special care should be taken when using tagged pointers, since it is likely that C compilers will not hazard two virtual addresses differing only in the upper byte. All interpretation of userspace memory addresses by the kernel assumes an address tag of 0x00. This includes, but is not limited to, addresses found in: - pointer arguments to system calls, including pointers in structures passed to system calls, - the stack pointer (sp), e.g. when interpreting it to deliver a signal, - the frame pointer (x29) and frame records, e.g. when interpreting them to generate a backtrace or call graph. Using non-zero address tags in any of these locations may result in an error code being returned, a (fatal) signal being raised, or other modes of failure. For these reasons, passing non-zero address tags to the kernel via system calls is forbidden, and using a non-zero address tag for sp is strongly discouraged. Programs maintaining a frame pointer and frame records that use non-zero address tags may suffer impaired or inaccurate debug and profiling visibility. Preserving tags --------------- Non-zero tags are not preserved when delivering signals. This means that signal handlers in applications making use of tags cannot rely on the tag information for user virtual addresses being maintained for fields inside siginfo_t. One exception to this rule is for signals raised in response to watchpoint debug exceptions, where the tag information will be preserved. The architecture prevents the use of a tagged PC, so the upper byte will be set to a sign-extension of bit 55 on exception return. Other considerations -------------------- Special care should be taken when using tagged pointers, since it is likely that C compilers will not hazard two virtual addresses differing only in the upper byte. Documentation/filesystems/f2fs.txt +20 −0 Original line number Diff line number Diff line Loading @@ -131,6 +131,26 @@ nobarrier This option can be used if underlying storage guarantees If this option is set, no cache_flush commands are issued but f2fs still guarantees the write ordering of all the data writes. fastboot This option is used when a system wants to reduce mount time as much as possible, even though normal performance can be sacrificed. extent_cache Enable an extent cache based on rb-tree, it can cache as many as extent which map between contiguous logical address and physical address per inode, resulting in increasing the cache hit ratio. Set by default. noextent_cache Disable an extent cache based on rb-tree explicitly, see the above extent_cache mount option. noinline_data Disable the inline data feature, inline data feature is enabled by default. data_flush Enable data flushing before checkpoint in order to persist data of regular and symlink. mode=%s Control block allocation mode which supports "adaptive" and "lfs". In "lfs" mode, there should be no random writes towards main area. io_bits=%u Set the bit size of write IO requests. It should be set with "mode=lfs". usrquota Enable plain user disk quota accounting. grpquota Enable plain group disk quota accounting. ================================================================================ DEBUGFS ENTRIES Loading Documentation/kernel-parameters.txt +7 −0 Original line number Diff line number Diff line Loading @@ -3347,6 +3347,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted. spia_pedr= spia_peddr= stack_guard_gap= [MM] override the default stack gap protection. The value is in page units and it defines how many pages prior to (for stacks growing down) resp. after (for stacks growing up) the main stack are reserved for no other mapping. Default value is 256 pages. stacktrace [FTRACE] Enabled the stack tracer on boot up. Loading Loading
Documentation/ABI/testing/sysfs-fs-f2fs +56 −0 Original line number Diff line number Diff line Loading @@ -74,3 +74,59 @@ Date: March 2014 Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com> Description: Controls the memory footprint used by f2fs. What: /sys/fs/f2fs/<disk>/trim_sections Date: February 2015 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> Description: Controls the trimming rate in batch mode. What: /sys/fs/f2fs/<disk>/cp_interval Date: October 2015 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> Description: Controls the checkpoint timing. What: /sys/fs/f2fs/<disk>/idle_interval Date: January 2016 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> Description: Controls the idle timing. What: /sys/fs/f2fs/<disk>/ra_nid_pages Date: October 2015 Contact: "Chao Yu" <chao2.yu@samsung.com> Description: Controls the count of nid pages to be readaheaded. What: /sys/fs/f2fs/<disk>/dirty_nats_ratio Date: January 2016 Contact: "Chao Yu" <chao2.yu@samsung.com> Description: Controls dirty nat entries ratio threshold, if current ratio exceeds configured threshold, checkpoint will be triggered for flushing dirty nat entries. What: /sys/fs/f2fs/<disk>/lifetime_write_kbytes Date: January 2016 Contact: "Shuoran Liu" <liushuoran@huawei.com> Description: Shows total written kbytes issued to disk. What: /sys/fs/f2fs/<disk>/inject_rate Date: May 2016 Contact: "Sheng Yong" <shengyong1@huawei.com> Description: Controls the injection rate. What: /sys/fs/f2fs/<disk>/inject_type Date: May 2016 Contact: "Sheng Yong" <shengyong1@huawei.com> Description: Controls the injection type. What: /sys/fs/f2fs/<disk>/reserved_blocks Date: June 2017 Contact: "Chao Yu" <yuchao0@huawei.com> Description: Controls current reserved blocks in system.
Documentation/Makefile +1 −1 Original line number Diff line number Diff line subdir-y := accounting auxdisplay blackfin connector \ filesystems filesystems ia64 laptops mic misc-devices \ filesystems filesystems ia64 laptops misc-devices \ networking pcmcia prctl ptp spi timers vDSO video4linux \ watchdog
Documentation/arm64/tagged-pointers.txt +47 −15 Original line number Diff line number Diff line Loading @@ -11,24 +11,56 @@ in AArch64 Linux. The kernel configures the translation tables so that translations made via TTBR0 (i.e. userspace mappings) have the top byte (bits 63:56) of the virtual address ignored by the translation hardware. This frees up this byte for application use, with the following caveats: this byte for application use. (1) The kernel requires that all user addresses passed to EL1 are tagged with tag 0x00. This means that any syscall parameters containing user virtual addresses *must* have their top byte cleared before trapping to the kernel. (2) Non-zero tags are not preserved when delivering signals. This means that signal handlers in applications making use of tags cannot rely on the tag information for user virtual addresses being maintained for fields inside siginfo_t. One exception to this rule is for signals raised in response to watchpoint debug exceptions, where the tag information will be preserved. Passing tagged addresses to the kernel -------------------------------------- (3) Special care should be taken when using tagged pointers, since it is likely that C compilers will not hazard two virtual addresses differing only in the upper byte. All interpretation of userspace memory addresses by the kernel assumes an address tag of 0x00. This includes, but is not limited to, addresses found in: - pointer arguments to system calls, including pointers in structures passed to system calls, - the stack pointer (sp), e.g. when interpreting it to deliver a signal, - the frame pointer (x29) and frame records, e.g. when interpreting them to generate a backtrace or call graph. Using non-zero address tags in any of these locations may result in an error code being returned, a (fatal) signal being raised, or other modes of failure. For these reasons, passing non-zero address tags to the kernel via system calls is forbidden, and using a non-zero address tag for sp is strongly discouraged. Programs maintaining a frame pointer and frame records that use non-zero address tags may suffer impaired or inaccurate debug and profiling visibility. Preserving tags --------------- Non-zero tags are not preserved when delivering signals. This means that signal handlers in applications making use of tags cannot rely on the tag information for user virtual addresses being maintained for fields inside siginfo_t. One exception to this rule is for signals raised in response to watchpoint debug exceptions, where the tag information will be preserved. The architecture prevents the use of a tagged PC, so the upper byte will be set to a sign-extension of bit 55 on exception return. Other considerations -------------------- Special care should be taken when using tagged pointers, since it is likely that C compilers will not hazard two virtual addresses differing only in the upper byte.
Documentation/filesystems/f2fs.txt +20 −0 Original line number Diff line number Diff line Loading @@ -131,6 +131,26 @@ nobarrier This option can be used if underlying storage guarantees If this option is set, no cache_flush commands are issued but f2fs still guarantees the write ordering of all the data writes. fastboot This option is used when a system wants to reduce mount time as much as possible, even though normal performance can be sacrificed. extent_cache Enable an extent cache based on rb-tree, it can cache as many as extent which map between contiguous logical address and physical address per inode, resulting in increasing the cache hit ratio. Set by default. noextent_cache Disable an extent cache based on rb-tree explicitly, see the above extent_cache mount option. noinline_data Disable the inline data feature, inline data feature is enabled by default. data_flush Enable data flushing before checkpoint in order to persist data of regular and symlink. mode=%s Control block allocation mode which supports "adaptive" and "lfs". In "lfs" mode, there should be no random writes towards main area. io_bits=%u Set the bit size of write IO requests. It should be set with "mode=lfs". usrquota Enable plain user disk quota accounting. grpquota Enable plain group disk quota accounting. ================================================================================ DEBUGFS ENTRIES Loading
Documentation/kernel-parameters.txt +7 −0 Original line number Diff line number Diff line Loading @@ -3347,6 +3347,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted. spia_pedr= spia_peddr= stack_guard_gap= [MM] override the default stack gap protection. The value is in page units and it defines how many pages prior to (for stacks growing down) resp. after (for stacks growing up) the main stack are reserved for no other mapping. Default value is 256 pages. stacktrace [FTRACE] Enabled the stack tracer on boot up. Loading
