[libvirt] [PATCH] qemu: Support for overriding NOFILE limit

This patch adds max_files option to qemu.conf which can be used to override system default limit on number of opened files that are allowed for qemu user. --- src/qemu/libvirtd_qemu.aug | 1 + src/qemu/qemu.conf | 4 +++- src/qemu/qemu_conf.c | 4 ++++ src/qemu/qemu_conf.h | 1 + src/qemu/qemu_process.c | 16 ++++++++++++++-- src/qemu/test_libvirtd_qemu.aug | 4 ++++ 6 files changed, 27 insertions(+), 3 deletions(-) diff --git a/src/qemu/libvirtd_qemu.aug b/src/qemu/libvirtd_qemu.aug index ad34e42..078e9c4 100644 --- a/src/qemu/libvirtd_qemu.aug +++ b/src/qemu/libvirtd_qemu.aug @@ -50,6 +50,7 @@ module Libvirtd_qemu = | bool_entry "allow_disk_format_probing" | bool_entry "set_process_name" | int_entry "max_processes" + | int_entry "max_files" | str_entry "lock_manager" | int_entry "max_queued" | int_entry "keepalive_interval" diff --git a/src/qemu/qemu.conf b/src/qemu/qemu.conf index c3f264f..6125d3b 100644 --- a/src/qemu/qemu.conf +++ b/src/qemu/qemu.conf @@ -301,9 +301,11 @@ # If max_processes is set to a positive integer, libvirt will use it to set # maximum number of processes that can be run by qemu user. This can be used to -# override default value set by host OS. +# override default value set by host OS. The same apply to max_files which +# set limit to maximum number of opened files. # # max_processes = 0 +# max_files = 0 # To enable 'Sanlock' project based locking of the file # content (to prevent two VMs writing to the same diff --git a/src/qemu/qemu_conf.c b/src/qemu/qemu_conf.c index 3766119..bc0a646 100644 --- a/src/qemu/qemu_conf.c +++ b/src/qemu/qemu_conf.c @@ -443,6 +443,10 @@ int qemudLoadDriverConfig(struct qemud_driver *driver, CHECK_TYPE("max_processes", VIR_CONF_LONG); if (p) driver->maxProcesses = p->l; + p = virConfGetValue(conf, "max_files"); + CHECK_TYPE("max_files", VIR_CONF_LONG); + if (p) driver->maxFiles = p->l; + p = virConfGetValue (conf, "lock_manager"); CHECK_TYPE ("lock_manager", VIR_CONF_STRING); if (p && p->str) { diff --git a/src/qemu/qemu_conf.h b/src/qemu/qemu_conf.h index 8161269..f5a0f60 100644 --- a/src/qemu/qemu_conf.h +++ b/src/qemu/qemu_conf.h @@ -105,6 +105,7 @@ struct qemud_driver { unsigned int setProcessName : 1; int maxProcesses; + int maxFiles; int max_queued; diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c index 9123f4c..105b895 100644 --- a/src/qemu/qemu_process.c +++ b/src/qemu/qemu_process.c @@ -2166,9 +2166,9 @@ qemuProcessPrepareChardevDevice(virDomainDefPtr def ATTRIBUTE_UNUSED, static int qemuProcessLimits(struct qemud_driver *driver) { - if (driver->maxProcesses > 0) { - struct rlimit rlim; + struct rlimit rlim; + if (driver->maxProcesses > 0) { rlim.rlim_cur = rlim.rlim_max = driver->maxProcesses; if (setrlimit(RLIMIT_NPROC, &rlim) < 0) { virReportSystemError(errno, @@ -2178,6 +2178,18 @@ qemuProcessLimits(struct qemud_driver *driver) } } + if (driver->maxFiles > 0) { + /* Max number of opened files is one greater than + * actual limit. See man setrlimit */ + rlim.rlim_cur = rlim.rlim_max = driver->maxFiles + 1; + if (setrlimit(RLIMIT_NOFILE, &rlim) < 0) { + virReportSystemError(errno, + _("cannot set max opened files to %d"), + driver->maxFiles); + return -1; + } + } + return 0; } diff --git a/src/qemu/test_libvirtd_qemu.aug b/src/qemu/test_libvirtd_qemu.aug index f7476ae..f841936 100644 --- a/src/qemu/test_libvirtd_qemu.aug +++ b/src/qemu/test_libvirtd_qemu.aug @@ -114,6 +114,8 @@ vnc_auto_unix_socket = 1 max_processes = 12345 +max_files = 67890 + lock_manager = \"fcntl\" keepalive_interval = 1 @@ -242,6 +244,8 @@ keepalive_count = 42 { "#empty" } { "max_processes" = "12345" } { "#empty" } +{ "max_files" = "67890" } +{ "#empty" } { "lock_manager" = "fcntl" } { "#empty" } { "keepalive_interval" = "1" } -- 1.7.3.4