aboutsummaryrefslogtreecommitdiff
path: root/block-raw-posix.c
AgeCommit message (Collapse)Author
2009-04-07push down vector linearization to posix-aio-compat.c (Christoph Hellwig)aliguori
Make all AIO requests vectored and defer linearization until the actual I/O thread. This prepares for using native preadv/pwritev. Also enables asynchronous direct I/O by handling that case in the I/O thread. Qcow and qcow2 propably want to be adopted to directly deal with multi-segment requests, but that can be implemented later. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7020 c046a42c-6fe2-441c-8c8c-71466251a162
2009-04-07Fix a few Sparse warningsblueswir1
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7016 c046a42c-6fe2-441c-8c8c-71466251a162
2009-04-05Fix the build for --disable-aioaliguori
This was reported by malc. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6993 c046a42c-6fe2-441c-8c8c-71466251a162
2009-04-05Add host_device support to qemu-img. (Nolan Leake)aliguori
This patch allows the use a host_device as the destination for "qemu-img convert". I added a ->bdrv_create function host_device. It merely verifies that the device exists and is large enough. A check is needed in the qemu-img convert loop to ensure that we write out all 0 sectors to the host_device. Otherwise they end up with stale garbage where all zero sectors were expected. I also made the check against bdrv_is_allocated enabled for everything _except_ host devices, since there is no point in making the block backend write a bunch of zeros just so that we can memcmp them immediately afterwards. Host devices can't benefit from this because there is no way to differentiate between a sector being unallocated because it was never written, or because it was written with all zeros and then made a trip through qemu-img convert. Finally, there is an unrelated fix for a typo in the error message printed if the destination device does not support ->bdrv_create. Signed-off-by: Nolan Leake <nolan <at> sigbus.net> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6978 c046a42c-6fe2-441c-8c8c-71466251a162
2009-03-30Fix wrong return valueblueswir1
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6959 c046a42c-6fe2-441c-8c8c-71466251a162
2009-03-28new scsi-generic abstraction, use SG_IO (Christoph Hellwig)aliguori
Okay, I started looking into how to handle scsi-generic I/O in the new world order. I think the best is to use the SG_IO ioctl instead of the read/write interface as that allows us to support scsi passthrough on disk/cdrom devices, too. See Hannes patch on the kvm list from August for an example. Now that we always do ioctls we don't need another abstraction than bdrv_ioctl for the synchronous requests for now, and for asynchronous requests I've added a aio_ioctl abstraction keeping it simple. Long-term we might want to move the ops to a higher-level abstraction and let the low-level code fill out the request header, but I'm lazy enough to leave that to the people trying to support scsi-passthrough on a non-Linux OS. Tested lightly by issuing various sg_ commands from sg3-utils in a guest to a host CDROM device. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6895 c046a42c-6fe2-441c-8c8c-71466251a162
2009-03-28FreeBSD host physical cdrom fixesblueswir1
This improves physical cdrom support on FreeBSD hosts to be almost as good as on Linux, with the only notable exception that you still need to either have the guest itself eject the disc if you want to take it out/change it, or do a change command in the monitor after taking out a disc in case a guest cannot eject it itself - otherwise the guest may continue using state (like size) of the old disc. Signed-off-by: Juergen Lock <nox@jelal.kn-bremen.de> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6888 c046a42c-6fe2-441c-8c8c-71466251a162
2009-03-13Fix regression introduced by r6824aliguori
The changes introduced by r6824 broke a subtle, and admittedly obscure, aspect of the block API. While bdrv_{pread,pwrite} return the number of bytes read or written upon success, bdrv_{read,write} returns a zero upon success. When using bdrv_pread for bdrv_read, special care must be taken to handle this case. This fixes certain guest images (notably linux-0.2 provided on the qemu website). Reported-by: malc <av1474@comtv.ru> Reported-by: Herve Poussineau <hpoussin@reactos.org> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6828 c046a42c-6fe2-441c-8c8c-71466251a162
2009-03-12Drop internal bdrv_pread()/bdrv_pwrite() APIs (Avi Kivity)aliguori
Now that scsi generic no longer uses bdrv_pread() and bdrv_pwrite(), we can drop the corresponding internal APIs, which overlap bdrv_read()/bdrv_write() and, being byte oriented, are unnatural for a block device. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6824 c046a42c-6fe2-441c-8c8c-71466251a162
2009-03-12Add internal scsi generic block API (Avi Kivity)aliguori
Add an internal API for the generic block layer to send scsi generic commands to block format driver. This means block format drivers no longer need to consider overloaded nb_sectors parameters. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6823 c046a42c-6fe2-441c-8c8c-71466251a162
2009-03-08Rename _BSD to HOST_BSD so that it's more obvious that it's defined by configureblueswir1
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6775 c046a42c-6fe2-441c-8c8c-71466251a162
2009-03-07Use C99 initializers for BlockDriver methodsaurel32
Consistently use the C99 named initializer format for the BlockDriver methods to make the method table more readable and more easily extensible. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6768 c046a42c-6fe2-441c-8c8c-71466251a162
2009-03-07Support for DragonFly BSD (Hasso Tepper)blueswir1
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6746 c046a42c-6fe2-441c-8c8c-71466251a162
2009-02-26fix raw_aio_remove (Stefano Stabellini)aliguori
Hi all, this small patch fixes a bug in the list iteration of raw_aio_remove. Cheers, Stefano Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6644 c046a42c-6fe2-441c-8c8c-71466251a162
2009-02-05block: remove error handling from qemu_malloc() callers (Avi Kivity)aliguori
Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6527 c046a42c-6fe2-441c-8c8c-71466251a162
2009-01-29fix raw_aio_read\write error handling (Stefano Stabellini)aliguori
Currently when qemu_paio_read or qemu_paio_write return an error we call qemu_aio_release without removing the request from the list. I know that in the current implementation qemu_paio_write\read don't return any error, but still the behavior is wrong, especially considering that the implementation of these two functions is likely to change in is the future. This patch fixes the problem adding a raw_aio_remove function that removes the callback from the queue and also calls qemu_aio_release. raw_aio_remove is called by raw_aio_read, raw_aio_write and raw_aio_cancel. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6470 c046a42c-6fe2-441c-8c8c-71466251a162
2009-01-24Rename sigev_signo to avoid FreeBSD problems (Juergen Lock)blueswir1
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6414 c046a42c-6fe2-441c-8c8c-71466251a162
2009-01-17Use kill instead of sigqueue: re-enables AIO on OpenBSDblueswir1
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6360 c046a42c-6fe2-441c-8c8c-71466251a162
2009-01-15global s/fflush(logfile)/qemu_log_flush()/ (Eduardo Habkost)aliguori
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6339 c046a42c-6fe2-441c-8c8c-71466251a162
2009-01-15Convert references to logfile/loglevel to use qemu_log*() macrosaliguori
This is a large patch that changes all occurrences of logfile/loglevel global variables to use the new qemu_log*() macros. Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6338 c046a42c-6fe2-441c-8c8c-71466251a162
2009-01-15Return -errno on write failure (Gleb Natapov)aliguori
Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6324 c046a42c-6fe2-441c-8c8c-71466251a162
2008-12-12Replace posix-aio with custom thread poolaliguori
glibc implements posix-aio as a thread pool and imposes a number of limitations. 1) it limits one request per-file descriptor. we hack around this by dup()'ing file descriptors which is hideously ugly 2) it's impossible to add new interfaces and we need a vectored read/write operation to properly support a zero-copy API. What has been suggested to me by glibc folks, is to implement whatever new interfaces we want and then it can eventually be proposed for standardization. This requires that we implement our own posix-aio implementation though. This patch implements posix-aio using pthreads. It immediately eliminates the need for fd pooling. It performs at least as well as the current posix-aio code (in some circumstances, even better). Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5996 c046a42c-6fe2-441c-8c8c-71466251a162
2008-11-13block: make raw aio signaling non-blocking (Gerd Hoffman)aliguori
This patch switches the read handle of the signaling pipe into non-blocking mode. This avoids unwanted blocking reads and also allows to read all bytes out of the signaling pipe in case we got signaled more that once before the handler ran. Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5716 c046a42c-6fe2-441c-8c8c-71466251a162
2008-10-14Fix previous commit (spotted by Robert Riebisch).aliguori
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5487 c046a42c-6fe2-441c-8c8c-71466251a162
2008-10-14Define O_DSYNC as O_SYNC if necessary.aliguori
O_DSYNC isn't available on OS X. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5486 c046a42c-6fe2-441c-8c8c-71466251a162
2008-10-14Expand cache= option and use write-through caching by defaultaliguori
This patch changes the cache= option to accept none, writeback, or writethough to control the host page cache behavior. By default, writethrough caching is now used which internally is implemented by using O_DSYNC to open the disk images. When using -snapshot, writeback is used by default since data integrity it not at all an issue. cache=none has the same behavior as cache=off previously. The later syntax is still supported by now deprecated. I also cleaned up the O_DIRECT implementation to avoid many of the #ifdefs. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5485 c046a42c-6fe2-441c-8c8c-71466251a162
2008-10-08Fix IO performance regression in sparcaliguori
Replace signalfd with signal handler/pipe. There is no way to interrupt the CPU execution loop when a file descriptor becomes readable. This results in a large performance regression in sparc emulation during bootup. This patch switches us to signal handler/pipe which was originally suggested by Ian Jackson. The signal handler lets us interrupt the CPU emulation loop while the write to a pipe lets us avoid the select/signal race condition. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5451 c046a42c-6fe2-441c-8c8c-71466251a162
2008-10-03Fix warning about missing return valueblueswir1
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5405 c046a42c-6fe2-441c-8c8c-71466251a162
2008-09-27Make compatfd fallback more robustaliguori
Be more friendly when signalfd() fails, and also add configure checks to detect that syscall(SYS_signalfd) actually works. malc pointed out that some installs do not have /usr/include/linux headers that are in sync with the glibc headers so why SYS_signalfd is defined, it's #defined to _NR_signalfd which is not defined in the /usr/include/linux header. While this is a distro bug, it doesn't hurt to do a more thorough job in detection. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5334 c046a42c-6fe2-441c-8c8c-71466251a162
2008-09-26Really fix the BSD build this timealiguori
struct aioinit isn't defined on BSD it appears so we need to guard everything in an #if defined(__linux__). Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5325 c046a42c-6fe2-441c-8c8c-71466251a162
2008-09-26Fix build on non-Linux unicesaliguori
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5324 c046a42c-6fe2-441c-8c8c-71466251a162
2008-09-26Implement an fd pool to get real AIO with posix-aioaliguori
This patch implements a simple fd pool to allow many AIO requests with posix-aio. The result is significantly improved performance (identical to that reported for linux-aio) for both cache=on and cache=off. The fundamental problem with posix-aio is that it limits itself to one thread per-file descriptor. I don't know why this is, but this patch provides a simple mechanism to work around this (duplicating the file descriptor). This isn't a great solution, but it seems like a reasonable intermediate step between posix-aio and a custom thread-pool to replace it. Ryan Harper will be posting some performance analysis he did comparing posix-aio with fd pooling against linux-aio. The size of the posix-aio thread pool and the fd pool were largely determined by him based on this analysis. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5323 c046a42c-6fe2-441c-8c8c-71466251a162
2008-09-26Fix build on FreeBSDaliguori
__GLIBC_PREREQ is defined in such a way that the ! cannot be used in front of it on FreeBSD. Also, -lpthread is not implied by the build and we definitely use it for compatfd support. While at it, I added a default initialization for posix-aio that seems to perform well in our testing. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5322 c046a42c-6fe2-441c-8c8c-71466251a162
2008-09-23Relax posix-aio restrictions on newer glibcsaliguori
RedHat 9 shipped glibc 2.3. Modern versions of glibc do not have the aio thread exit issue that the comment references. This patch adjusts the check to only limit aio_init on glibc versions < 2.4. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5304 c046a42c-6fe2-441c-8c8c-71466251a162
2008-09-22Refactor AIO to allow multiple AIO implementationsaliguori
This patch refactors the AIO layer to allow multiple AIO implementations. It's only possible because of the recent signalfd() patch. Right now, the AIO infrastructure is pretty specific to the block raw backend. For other block devices to implement AIO, the qemu_aio_wait function must support registration. This patch introduces a new function, qemu_aio_set_fd_handler, which can be used to register a file descriptor to be called back. qemu_aio_wait() now polls a set of file descriptors registered with this function until one becomes readable or writable. This patch should allow the implementation of alternative AIO backends (via a thread pool or linux-aio) and AIO backends in non-traditional block devices (like NBD). Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5297 c046a42c-6fe2-441c-8c8c-71466251a162
2008-09-22Do not allow AIO to be inited multiple timesaliguori
This prevents two signalfd() threads from being spawned. This problem was originally spotted by Blue Swirl. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5289 c046a42c-6fe2-441c-8c8c-71466251a162
2008-09-16block-raw is not a protocolaliguori
The protocol_name "file" was added to the block driver when async IO was introduced. This can be used to select that a file is treated as a raw device instead of probing for the type. However, protocols are not subject to path interpretation which cases qcow2 images with raw base images to not function is the path was specified relatively. The fix is simply to remove the protocol_name from the raw block driver. The proper way to force the use of a raw block format is to use the format= option with -drive. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5233 c046a42c-6fe2-441c-8c8c-71466251a162
2008-09-15Make sure to define fd_open when not on Linuxaliguori
My previous commit broke the build. This was spotted by C.W. Betts. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5231 c046a42c-6fe2-441c-8c8c-71466251a162
2008-09-15Use common objects for qemu-img and qemu-nbdaliguori
Right now, we sprinkle #if defined(QEMU_IMG) && defined(QEMU_NBD) all over the code. It's ugly and causes us to have to build multiple object files for linking against qemu and the tools. This patch introduces a new file, qemu-tool.c which contains enough for qemu-img, qemu-nbd, and QEMU to all share the same objects. This also required getting qemu-nbd to be a bit more Windows friendly. I also changed the Windows block-raw to use normal IO instead of overlapping IO since we don't actually do AIO yet on Windows. I changed the various #if 0's to #if WIN32_AIO to make it easier for someone to eventually fix AIO on Windows. After this patch, there are no longer any #ifdef's related to qemu-img and qemu-nbd. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5226 c046a42c-6fe2-441c-8c8c-71466251a162
2008-09-11Only build compatfd when using AIO and make sure to always init AIOaliguori
OpenBSD doesn't use AIO so don't try to build compatfd when not using AIO. Also make sure to call qemu_aio_init() from bdrv_init. Everything that uses bdrv calls bdrv_init so it makes sense to init aio from there instead of in every single tool. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5197 c046a42c-6fe2-441c-8c8c-71466251a162
2008-09-11Make sure to read siginfo from signalfdaliguori
Otherwise, we'll idle at 100% cpu. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5195 c046a42c-6fe2-441c-8c8c-71466251a162
2008-09-10Use signalfd() to work around signal/select racealiguori
This patch introduces signalfd() to work around the signal/select race in checking for AIO completions. For platforms that don't support signalfd(), we emulate it with threads. There was a long discussion about this approach. I don't believe there are any fundamental problems with this approach and I believe eliminating the use of signals is a good thing. I've tested Windows and Linux using Windows and Linux guests. I've also checked for disk IO performance regressions. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5187 c046a42c-6fe2-441c-8c8c-71466251a162
2008-08-24Add missing FreeBSD #include (Juergen Lock)blueswir1
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5081 c046a42c-6fe2-441c-8c8c-71466251a162
2008-08-15Preliminary OpenBSD host support (based on OpenBSD patches by Todd T. Fries)blueswir1
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5012 c046a42c-6fe2-441c-8c8c-71466251a162
2008-08-15Use AIO only if host supports it (based on OpenBSD patches by Todd T. Fries)blueswir1
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5010 c046a42c-6fe2-441c-8c8c-71466251a162
2008-07-03Add a parameter to disable host cache, by Laurent Vivier.ths
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4836 c046a42c-6fe2-441c-8c8c-71466251a162
2008-05-28Align file accesses with cache=off (O_DIRECT) (Kevin Wolf, Laurent Vivier)bellard
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4599 c046a42c-6fe2-441c-8c8c-71466251a162
2008-05-07Revert 4367blueswir1
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4377 c046a42c-6fe2-441c-8c8c-71466251a162
2008-05-06Align file accesses with cache=off (Kevin Wolf, Laurent Vivier)blueswir1
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4367 c046a42c-6fe2-441c-8c8c-71466251a162
2008-01-06restore original values for ai.aio_threads and ai.aio_numbellard
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3896 c046a42c-6fe2-441c-8c8c-71466251a162