1spufs(7) Miscellaneous Information Manual spufs(7)
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6 spufs - SPU filesystem
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9 The SPU filesystem is used on PowerPC machines that implement the Cell
10 Broadband Engine Architecture in order to access Synergistic Processor
11 Units (SPUs).
12 The filesystem provides a name space similar to POSIX shared memory or
14 message queues. Users that have write permissions on the filesystem
15 can use spu_create(2) to establish SPU contexts under the spufs root
16 directory.
17 Every SPU context is represented by a directory containing a predefined
19 set of files. These files can be used for manipulating the state of
20 the logical SPU. Users can change permissions on the files, but can't
21 add or remove files.
22 Mount options
24 uid=<uid>
25 Set the user owning the mount point; the default is 0 (root).
26 gid=<gid>
28 Set the group owning the mount point; the default is 0 (root).
29 mode=<mode>
31 Set the mode of the top-level directory in spufs, as an octal
32 mode string. The default is 0775.
33 Files
35 The files in spufs mostly follow the standard behavior for regular sys‐
36 tem calls like read(2) or write(2), but often support only a subset of
37 the operations supported on regular filesystems. This list details the
38 supported operations and the deviations from the standard behavior de‐
39 scribed in the respective man pages.
40 All files that support the read(2) operation also support readv(2) and
42 all files that support the write(2) operation also support writev(2).
43 All files support the access(2) and stat(2) family of operations, but
44 for the latter call, the only fields of the returned stat structure
45 that contain reliable information are st_mode, st_nlink, st_uid, and
46 st_gid.
47 All files support the chmod(2)/fchmod(2) and chown(2)/fchown(2) opera‐
49 tions, but will not be able to grant permissions that contradict the
50 possible operations (e.g., read access on the wbox file).
51 The current set of files is:
53 /capabilities
55 Contains a comma-delimited string representing the capabilities
56 of this SPU context. Possible capabilities are:
57 sched This context may be scheduled.
59 step This context can be run in single-step mode, for debug‐
61 ging.
62 New capabilities flags may be added in the future.
64 /mem the contents of the local storage memory of the SPU. This can
66 be accessed like a regular shared memory file and contains both
67 code and data in the address space of the SPU. The possible op‐
68 erations on an open mem file are:
69 read(2), pread(2),