blog: Add blog post on new vfs stack - #520
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razvand
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All good, thanks.
Reviewed-by: Razvan Deaconescu razvand@unikraft.io
StefanJum
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Looks great @andreittr, some minor linting comments (basically add empty lines after headings and before lists). Other than that everything is ok, I'll approve after the changes.
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| #### Insufficient Abstraction | ||
| In vfscore, a file's open state (e.g., `lseek` position) and file descriptor are tightly bound to the file object, appearing as fields in its struct. |
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| #### Insufficient Abstraction | |
| In vfscore, a file's open state (e.g., `lseek` position) and file descriptor are tightly bound to the file object, appearing as fields in its struct. | |
| #### Insufficient Abstraction | |
| In vfscore, a file's open state (e.g., `lseek` position) and file descriptor are tightly bound to the file object, appearing as fields in its struct. |
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| #### Files == Paths | ||
| In a similar limitation to the above, vfscore views the filesystem as a _reversible_ mapping of paths to files, implying another 1:1 relationship that does not exist in practice. |
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| #### Files == Paths | |
| In a similar limitation to the above, vfscore views the filesystem as a _reversible_ mapping of paths to files, implying another 1:1 relationship that does not exist in practice. | |
| #### Files == Paths | |
| In a similar limitation to the above, vfscore views the filesystem as a _reversible_ mapping of paths to files, implying another 1:1 relationship that does not exist in practice. |
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| #### Absolute Lookups | ||
| Building on its assumptions about the mapping of paths to files, vfscore treats all lookups as absolute, roughly following two steps: (1) look up absolute path prefix in mount table to determine mount root, and (2) delegate lookup relative to mount root to driver. |
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| #### Absolute Lookups | |
| Building on its assumptions about the mapping of paths to files, vfscore treats all lookups as absolute, roughly following two steps: (1) look up absolute path prefix in mount table to determine mount root, and (2) delegate lookup relative to mount root to driver. | |
| #### Absolute Lookups | |
| Building on its assumptions about the mapping of paths to files, vfscore treats all lookups as absolute, roughly following two steps: (1) look up absolute path prefix in mount table to determine mount root, and (2) delegate lookup relative to mount root to driver. |
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| #### Monolithic Nature | ||
| Unlike most Unikraft core libraries, and counter to the unikernel philosophy, vfscore is unusually monolithic, bearing responsibility across many abstraction layers. |
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| #### Monolithic Nature | |
| Unlike most Unikraft core libraries, and counter to the unikernel philosophy, vfscore is unusually monolithic, bearing responsibility across many abstraction layers. | |
| #### Monolithic Nature | |
| Unlike most Unikraft core libraries, and counter to the unikernel philosophy, vfscore is unusually monolithic, bearing responsibility across many abstraction layers. |
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| To address vfscore's issues, as well as to lay the groundwork for future development, we introduce the Unikraft filesystem stack, anchored by two core libraries: | ||
| - `ukfs` - what is _a_ filesystem; driver registration & lookup | ||
| - `posix-vfs` what is _the_ filesystem (VFS); all userspace-facing operations |
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| To address vfscore's issues, as well as to lay the groundwork for future development, we introduce the Unikraft filesystem stack, anchored by two core libraries: | |
| - `ukfs` - what is _a_ filesystem; driver registration & lookup | |
| - `posix-vfs` what is _the_ filesystem (VFS); all userspace-facing operations | |
| To address vfscore's issues, as well as to lay the groundwork for future development, we introduce the Unikraft filesystem stack, anchored by two core libraries: | |
| - `ukfs` - what is _a_ filesystem; driver registration & lookup | |
| - `posix-vfs` what is _the_ filesystem (VFS); all userspace-facing operations |
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| But with great power comes great responsibility, one that some drivers may not wish to burden themselves with; a non-exhaustive list of these responsibilities is: | ||
| - volume-wide state | ||
| - volume lifetime management |
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| But with great power comes great responsibility, one that some drivers may not wish to burden themselves with; a non-exhaustive list of these responsibilities is: | |
| - volume-wide state | |
| - volume lifetime management | |
| But with great power comes great responsibility, one that some drivers may not wish to burden themselves with; a non-exhaustive list of these responsibilities is: | |
| - volume-wide state | |
| - volume lifetime management |
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| As part of this full-stack release, we introduced several new core libraries: | ||
| - `ukfs` -- filesystem API; compile-time driver registration; runtime driver lookup | ||
| - `ukfs-ramfs` -- memory-resident volatile filesystem |
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| As part of this full-stack release, we introduced several new core libraries: | |
| - `ukfs` -- filesystem API; compile-time driver registration; runtime driver lookup | |
| - `ukfs-ramfs` -- memory-resident volatile filesystem | |
| As part of this full-stack release, we introduced several new core libraries: | |
| - `ukfs` -- filesystem API; compile-time driver registration; runtime driver lookup | |
| - `ukfs-ramfs` -- memory-resident volatile filesystem |
Signed-off-by: Andrei Tatar <ttr@unikraft.io>
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Pushed update addressing comments. |
StefanJum
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All good, thanks.
Approved-by: Stefan Jumarea stefanjumarea02@gmail.com
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This blog post provides a technical overview of the new VFS stack introduced in Unikraft 0.20.0.