62 Commits

Author SHA1 Message Date
Michal Privoznik
f1ac53772d qemuDomainSetupDisk: Accept @src
The aim to make it look as close to
qemuDomainNamespaceSetupDisk() as possible. The latter will call
the former and this change makes that diff easier to read.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-08-03 19:40:36 +02:00
Michal Privoznik
277412df51 qemuNamespaceMknodPaths: Turn @paths into string list
Every caller does the same - counts the number of items in a
string list they have, only to pass the number to
qemuDomainNamespaceMknodPaths(). This is needless - the function
can accept the string list and count the items itself.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-08-03 19:40:36 +02:00
Michal Privoznik
f17088975d qemuDomainNamespaceMknodPaths: Create more files in one go
While the previous commit prepared the helper function run in a
forked off helper (with corresponding struct), this commit
modifies the caller, which now create all files requested in a
single process and does not fork off for every single path.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-08-03 19:40:35 +02:00
Michal Privoznik
86d2e323f4 qemuDomainAttachDeviceMknodHelper: Create more files in a single go
So far, when attaching a device needs two or more /dev nodes
created into a domain, we fork off and run the helper for every
node separately. For majority of devices this is okay, because
they need no or one node created anyway. But the idea is to use
this attach code to build the namespace when starting a domain,
in which case there will be way more nodes than one.

To achieve this, the recursive approach for handling symlinks has
to be turned into an iterative one.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-08-03 19:40:35 +02:00
Michal Privoznik
bf9aeab4f0 qemuDomainAttachDeviceMknodRecursive: Isolate bind mounted devices condition
When attaching a device into a domain, the corresponding /dev
node might need to be created in the domain's namespace. For some
types of files we call mknod(), for symlinks we call symlink(),
but for others - which exist in the host namespace - we need to
so called 'bind mount' them (which is a way of passing a
file/directory between mount namespaces). There is this condition
in qemuDomainAttachDeviceMknodRecursive() which decides whether a
bind mount will be used, move it into a separate function so that
it can be reused later.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-08-03 19:40:35 +02:00
Michal Privoznik
08277c2bc6 qemu_domain_namespace.c: Rename qemuDomainAttachDeviceMknodData
This structure is going to be used from not only device attach
code, but also when building the namespace. Moreover, the code
lives in a separate file so the chances of clashing with another
name are minimal.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-08-03 19:40:35 +02:00
Michal Privoznik
759921d47c qemuDomainAttachDeviceMknodHelper: Don't leak data->target
It's not really a problem since this is a helper process that
dies as soon as the helper function returns, but the cleanup code
will be replaced with a function soon and this change prepares
the code for that.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-08-03 19:40:35 +02:00
Michal Privoznik
9d8d42137a qemuDomainNamespaceSetupHostdev: Create paths in one go
While qemuDomainNamespaceMknodPaths() doesn't actually create
files in the namespace in one go (it forks for each path), it a
few commits time it will.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-08-03 19:40:34 +02:00
Michal Privoznik
c467b07e27 qemu_domain_namespace: Check for namespace enablement earlier
Functions that create a device node after domain startup (used
from hotplug) will get a list of paths they want to create and
eventually call qemuDomainNamespaceMknodPaths() which then checks
whether domain mount namespace is enabled in the first place.
Alternatively, on device hotunplug, we might want to delete a
path inside domain namespace in which case
qemuDomainNamespaceUnlinkPaths() checks whether the namespace is
enabled. While this is not dangerous, it certainly burns a couple
of CPU cycles needlessly.

Check whether mount namespace is enabled upfront.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-08-03 19:40:34 +02:00
Michal Privoznik
68a4320b95 qemu_domain_namespace: Drop unused @cfg argument
There is a lot of functions called from
qemuDomainBuildNamespace() that accept @cfg
(virQEMUDriverConfigPtr) as an argument and don't use it.
Historically, it was done so that all qemuDomainSetupAll*()
functions look the same.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-08-03 19:40:34 +02:00
Michal Privoznik
764eaf1aa4 qemu_domain_namespace: Rename qemuDomainCreateNamespace()
The name of this function is not very helpful, because it doesn't
create anything, it just flips a bit in a bitmask when domain is
starting up. Move the function internals into qemu_process.c and
forget the function ever existed.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-08-03 19:40:33 +02:00
Michal Privoznik
90eee87569 qemu: Separate out namespace handling code
The qemu_domain.c file is big as is and we should split it into
separate semantic blocks. Start with code that handles domain
namespaces.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-08-03 19:32:27 +02:00