Re: [Libguestfs] [PATCH 2/3] New API: guestfs_blockdev_setra: Adjust readahead for filesystems and devices.

This adds a binding for 'blockdev --setra', allowing you to adjust the readahead parameter for filesystems and devices. --- daemon/blockdev.c | 30 ++++++++++++++++++++---------- generator/actions.ml | 14 ++++++++++++++ 2 files changed, 34 insertions(+), 10 deletions(-) diff --git a/daemon/blockdev.c b/daemon/blockdev.c index 8a7b1a8..6e8821d 100644 --- a/daemon/blockdev.c +++ b/daemon/blockdev.c @@ -62,7 +62,7 @@ call_blockdev (const char *device, const char *switc, int extraarg, int prints) */ udev_settle (); - if (extraarg > 0) { + if (extraarg >= 0) { snprintf (buf, sizeof buf, "%d", extraarg); argv[2] = buf; argv[3] = device; @@ -89,33 +89,43 @@ call_blockdev (const char *device, const char *switc, int extraarg, int prints) } int +do_blockdev_setra (const char *device, int sectors) +{ + if (sectors < 0) { + reply_with_error ("readahead sectors must be >= 0"); + return -1; + } + return (int) call_blockdev (device, "--setra", sectors, 0); +} + +int do_blockdev_setro (const char *device) { - return (int) call_blockdev (device, "--setro", 0, 0); + return (int) call_blockdev (device, "--setro", -1, 0); } int do_blockdev_setrw (const char *device) { - return (int) call_blockdev (device, "--setrw", 0, 0); + return (int) call_blockdev (device, "--setrw", -1, 0); } int do_blockdev_getro (const char *device) { - return (int) call_blockdev (device, "--getro", 0, 1); + return (int) call_blockdev (device, "--getro", -1, 1); } int do_blockdev_getss (const char *device) { - return (int) call_blockdev (device, "--getss", 0, 1); + return (int) call_blockdev (device, "--getss", -1, 1); } int do_blockdev_getbsz (const char *device) { - return (int) call_blockdev (device, "--getbsz", 0, 1); + return (int) call_blockdev (device, "--getbsz", -1, 1); } int @@ -128,23 +138,23 @@ do_blockdev_setbsz (const char *device, int blocksize) int64_t do_blockdev_getsz (const char *device) { - return call_blockdev (device, "--getsz", 0, 1); + return call_blockdev (device, "--getsz", -1, 1); } int64_t do_blockdev_getsize64 (const char *device) { - return call_blockdev (device, "--getsize64", 0, 1); + return call_blockdev (device, "--getsize64", -1, 1); } int do_blockdev_flushbufs (const char *device) { - return call_blockdev (device, "--flushbufs", 0, 0); + return call_blockdev (device, "--flushbufs", -1, 0); } int do_blockdev_rereadpt (const char *device) { - return call_blockdev (device, "--rereadpt", 0, 0); + return call_blockdev (device, "--rereadpt", -1, 0); } diff --git a/generator/actions.ml b/generator/actions.ml index fe492e6..baa7679 100644 --- a/generator/actions.ml +++ b/generator/actions.ml @@ -12003,6 +12003,20 @@ This is the same as the C<lstat(2)> system call." }; longdesc = "\ This is the internal call which implements C<guestfs_lstatnslist>." }; + { defaults with + name = "blockdev_setra"; + style = RErr, [Device "device"; Int "sectors"], []; + proc_nr = Some 424; + tests = [ + InitEmpty, Always, TestRun ( + [["blockdev_setra"; "/dev/sda"; "1024" ]]), [] + ]; + shortdesc = "set readahead"; + longdesc = "\ +Set readahead (in 512-byte sectors) for the device. + +This uses the L<blockdev(8)> command." }; + ] (* Non-API meta-commands available only in guestfish.