search for: blk_init

This commit delays the point at which bdrv_new (and hence blk_open on the underlying device) is called from blk_init to blk_connect. This ensures that in an inbound live migrate, the block device is not opened until it has been closed at the other end. This is in preparation for supporting devices with open/close consistency without using O_DIRECT. This commit does NOT itself change O_DIRECT semantics. Signed-of...

...<stefano.stabellini@eu.citrix.com> --- hw/xen_disk.c | 34 +++++++++++++++++++++++++++------- 1 files changed, 27 insertions(+), 7 deletions(-) diff --git a/hw/xen_disk.c b/hw/xen_disk.c index 096d1c9..faaa065 100644 --- a/hw/xen_disk.c +++ b/hw/xen_disk.c @@ -616,12 +616,14 @@ static int blk_init(struct XenDevice *xendev) { struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev); int index, qflags, have_barriers, info = 0; - char *h; /* read xenstore entries */ if (blkdev->params == NULL) { + char *h = NULL; blkdev->params =...

...lini <stefano.stabellini@eu.citrix.com> --- hw/xen_disk.c | 29 ++++++++++++++++++++++------- 1 files changed, 22 insertions(+), 7 deletions(-) diff --git a/hw/xen_disk.c b/hw/xen_disk.c index 096d1c9..eec05dd 100644 --- a/hw/xen_disk.c +++ b/hw/xen_disk.c @@ -616,12 +616,14 @@ static int blk_init(struct XenDevice *xendev) { struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev); int index, qflags, have_barriers, info = 0; - char *h; /* read xenstore entries */ if (blkdev->params == NULL) { + char *h = NULL; blkdev->params =...

Hello! I was asking for help on the Freenode channel, and I was pointed here. I have a situation where, using xl, I can create a functional PV domU, with or without pv-grub, but I cannot access the console. Firing up xend and using xm works without trouble. Since xend and company is being deprecated, I would like to transition to using the xl toolstack. The system is an Arch Linux system

...tefano Stabellini <stefano.stabellini@eu.citrix.com> --- hw/xen_disk.c | 16 +++++++++++----- 1 files changed, 11 insertions(+), 5 deletions(-) diff --git a/hw/xen_disk.c b/hw/xen_disk.c index 096d1c9..801da58 100644 --- a/hw/xen_disk.c +++ b/hw/xen_disk.c @@ -616,11 +616,13 @@ static int blk_init(struct XenDevice *xendev) { struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev); int index, qflags, have_barriers, info = 0; - char *h; + char *h = NULL; /* read xenstore entries */ if (blkdev->params == NULL) { blkdev->params = xens...

...++++++ filters/cache/cache.c | 57 +++++++++++++++++++++++++++++++------------ 2 files changed, 49 insertions(+), 15 deletions(-) diff --git a/filters/cache/blk.h b/filters/cache/blk.h index 24bf6a1..ab9134e 100644 --- a/filters/cache/blk.h +++ b/filters/cache/blk.h @@ -40,6 +40,13 @@ extern int blk_init (void); /* Close the cache, free the bitmap. */ extern void blk_free (void); +/*---------------------------------------------------------------------- + * ** NOTE ** + * + * An exclusive lock must be held when you call any function below + * this line. + */ + /* Allocate or resize the cache fi...

This patch series enhances the cache filter in a few ways, primarily adding a "cache-on-read" feature (similar to qemu's copyonread); and adding the ability to limit the cache size and the antecedent of that which is having a method to reclaim cache blocks. As the cache is stored as a sparse temporary file, reclaiming cache blocks simply means punching holes in the temporary file.

...ff --git a/filters/cache/blk.c b/filters/cache/blk.c index 4000276..b256446 100644 --- a/filters/cache/blk.c +++ b/filters/cache/blk.c @@ -53,6 +53,7 @@ #include "cache.h" #include "blk.h" +#include "lru.h" /* The cache. */ static int fd = -1; @@ -80,6 +81,8 @@ blk_init (void) size_t len; char *template; + lru_init (); + bitmap_init (&bm, BLKSIZE, 2 /* bits per block */); tmpdir = getenv ("TMPDIR"); @@ -115,6 +118,8 @@ blk_free (void) close (fd); bitmap_free (&bm); + + lru_free (); } int @@ -128,6 +133,9 @@ blk_set...

...ff --git a/filters/cache/blk.c b/filters/cache/blk.c index 4000276..b256446 100644 --- a/filters/cache/blk.c +++ b/filters/cache/blk.c @@ -53,6 +53,7 @@ #include "cache.h" #include "blk.h" +#include "lru.h" /* The cache. */ static int fd = -1; @@ -80,6 +81,8 @@ blk_init (void) size_t len; char *template; + lru_init (); + bitmap_init (&bm, BLKSIZE, 2 /* bits per block */); tmpdir = getenv ("TMPDIR"); @@ -115,6 +118,8 @@ blk_free (void) close (fd); bitmap_free (&bm); + + lru_free (); } int @@ -128,6 +133,9 @@ blk_set...

Patch 1 is the same as last time, except for a minor comment fix. Patch 2 should address everything that Eric mentioned in his review, and has been retested. Rich.

..."reclaim.h" /* The cache. */ static int fd = -1; @@ -69,7 +72,7 @@ static int fd = -1; static struct bitmap bm; enum bm_entry { - BLOCK_NOT_CACHED = 0, + BLOCK_NOT_CACHED = 0, /* assumed to be zero by reclaim code */ BLOCK_CLEAN = 1, BLOCK_DIRTY = 3, }; @@ -80,10 +83,7 @@ blk_init (void) const char *tmpdir; size_t len; char *template; - - lru_init (); - - bitmap_init (&bm, BLKSIZE, 2 /* bits per block */); + struct statvfs statvfs; tmpdir = getenv ("TMPDIR"); if (!tmpdir) @@ -108,6 +108,24 @@ blk_init (void) unlink (template); + /* C...

v4: https://www.redhat.com/archives/libguestfs/2019-January/msg00032.html v5: - Now we set the block size at run time. I'd like to say that I was able to test this change, but unfortunately I couldn't find any easy way to create a filesystem on x86-64 with a block size > 4K. Ext4 doesn't support it at all, and XFS doesn't support block size > page size (and I

There's enough here to need a review; some of it probably needs backporting to stable-1.12. This probably breaks tests on Haiku or other platforms that have not been as on-the-ball about atomic CLOEXEC; feel free to report issues that arise, and I'll help come up with workarounds (even if we end up leaving a rare fd leak on less-capable systems). Meanwhile, I'm still working on my

...e. + * + * reclaim_blk is the last block that we will looked at. + */ +enum reclaim_state { + NOT_RECLAIMING = 0, + RECLAIMING_LRU = 1, + RECLAIMING_ANY = 2, +}; + +static enum reclaim_state reclaiming = NOT_RECLAIMING; +static uint64_t reclaim_blk; +#endif + +static void reclaim (void); + int blk_init (void) { @@ -146,6 +173,8 @@ blk_read (struct nbdkit_next_ops *next_ops, void *nxdata, off_t offset = blknum * BLKSIZE; enum bm_entry state = bitmap_get_blk (&bm, blknum, BLOCK_NOT_CACHED); + reclaim (); + nbdkit_debug ("cache: blk_read block %" PRIu64 " (offset %&qu...

...e. + * + * reclaim_blk is the last block that we will looked at. + */ +enum reclaim_state { + NOT_RECLAIMING = 0, + RECLAIMING_LRU = 1, + RECLAIMING_ANY = 2, +}; + +static enum reclaim_state reclaiming = NOT_RECLAIMING; +static uint64_t reclaim_blk; +#endif + +static void reclaim (void); + int blk_init (void) { @@ -146,6 +173,8 @@ blk_read (struct nbdkit_next_ops *next_ops, void *nxdata, off_t offset = blknum * BLKSIZE; enum bm_entry state = bitmap_get_blk (&bm, blknum, BLOCK_NOT_CACHED); + reclaim (); + nbdkit_debug ("cache: blk_read block %" PRIu64 " (offset %&qu...

...bm[1]. + * + * reclaim_blk is the last block that we looked at. + */ +enum reclaim_state { + NOT_RECLAIMING = 0, + RECLAIMING_LRU = 1, + RECLAIMING_ANY = 2, +}; + +static enum reclaim_state reclaiming = NOT_RECLAIMING; +static uint64_t reclaim_blk; +#endif + +static void reclaim (void); + int blk_init (void) { @@ -146,6 +176,8 @@ blk_read (struct nbdkit_next_ops *next_ops, void *nxdata, off_t offset = blknum * BLKSIZE; enum bm_entry state = bitmap_get_blk (&bm, blknum, BLOCK_NOT_CACHED); + reclaim (); + nbdkit_debug ("cache: blk_read block %" PRIu64 " (offset %&qu...

These are essentially identical to what was previously posted as patches 6/9 through 9/9 here: https://www.redhat.com/archives/libguestfs/2018-December/msg00145.html except that it has been rebased onto the current git master and retested thoroughly. Rich.

v3 was broken by a bad rebase, so let's forget about that one. Compared to v2: - Patch 1 is the same except for a minor comment change. - Patch 2 splits the reclaim code into a separate file (filters/cache/reclaim.c) - Addressed Eric's comments from his review of v2. - Retested on Linux and FreeBSD.

This is a major rewrite compared to my v1 series, where I've tried a lot harder to ensure that we still accommodate building on Haiku (although I have not actually yet fired up a Haiku VM to try it for myself). I also managed to make the sh plugin fully parallel, on capable platforms. See also my question on patch 10 on whether I've picked the best naming convention. Eric Blake (17):