When all we do with an Error we receive into a local variable is
propagating to somewhere else, we can just as well receive it there
right away.  Convert
    if (!foo(..., &err)) {
        ...
        error_propagate(errp, err);
        ...
        return ...
    }
to
    if (!foo(..., errp)) {
        ...
        ...
        return ...
    }
where nothing else needs @err.  Coccinelle script:
    @rule1 forall@
    identifier fun, err, errp, lbl;
    expression list args, args2;
    binary operator op;
    constant c1, c2;
    symbol false;
    @@
         if (
    (
    -        fun(args, &err, args2)
    +        fun(args, errp, args2)
    |
    -        !fun(args, &err, args2)
    +        !fun(args, errp, args2)
    |
    -        fun(args, &err, args2) op c1
    +        fun(args, errp, args2) op c1
    )
            )
         {
             ... when != err
                 when != lbl:
                 when strict
    -        error_propagate(errp, err);
             ... when != err
    (
             return;
    |
             return c2;
    |
             return false;
    )
         }
    @rule2 forall@
    identifier fun, err, errp, lbl;
    expression list args, args2;
    expression var;
    binary operator op;
    constant c1, c2;
    symbol false;
    @@
    -    var = fun(args, &err, args2);
    +    var = fun(args, errp, args2);
         ... when != err
         if (
    (
             var
    |
             !var
    |
             var op c1
    )
            )
         {
             ... when != err
                 when != lbl:
                 when strict
    -        error_propagate(errp, err);
             ... when != err
    (
             return;
    |
             return c2;
    |
             return false;
    |
             return var;
    )
         }
    @depends on rule1 || rule2@
    identifier err;
    @@
    -    Error *err = NULL;
         ... when != err
Not exactly elegant, I'm afraid.
The "when != lbl:" is necessary to avoid transforming
         if (fun(args, &err)) {
             goto out
         }
         ...
     out:
         error_propagate(errp, err);
even though other paths to label out still need the error_propagate().
For an actual example, see sclp_realize().
Without the "when strict", Coccinelle transforms vfio_msix_setup(),
incorrectly.  I don't know what exactly "when strict" does, only that
it helps here.
The match of return is narrower than what I want, but I can't figure
out how to express "return where the operand doesn't use @err".  For
an example where it's too narrow, see vfio_intx_enable().
Silently fails to convert hw/arm/armsse.c, because Coccinelle gets
confused by ARMSSE being used both as typedef and function-like macro
there.  Converted manually.
Line breaks tidied up manually.  One nested declaration of @local_err
deleted manually.  Preexisting unwanted blank line dropped in
hw/riscv/sifive_e.c.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200707160613.848843-35-armbru@redhat.com>
		
	
			
		
			
				
	
	
		
			468 lines
		
	
	
		
			12 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			468 lines
		
	
	
		
			12 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * qdev property parsing
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 * (parts specific for qemu-system-*)
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 *
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 * This file is based on code from hw/qdev-properties.c from
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 * commit 074a86fccd185616469dfcdc0e157f438aebba18,
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 * Copyright (c) Gerd Hoffmann <kraxel@redhat.com> and other contributors.
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 *
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 * This work is licensed under the terms of the GNU GPL, version 2 or later.
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 * See the COPYING file in the top-level directory.
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 */
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#include "qemu/osdep.h"
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#include "audio/audio.h"
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#include "net/net.h"
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#include "hw/qdev-properties.h"
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#include "qapi/error.h"
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#include "qapi/qmp/qerror.h"
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#include "sysemu/block-backend.h"
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#include "sysemu/blockdev.h"
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#include "hw/block/block.h"
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#include "net/hub.h"
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#include "qapi/visitor.h"
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#include "chardev/char-fe.h"
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#include "sysemu/iothread.h"
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#include "sysemu/tpm_backend.h"
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static bool check_prop_still_unset(DeviceState *dev, const char *name,
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                                   const void *old_val, const char *new_val,
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                                   Error **errp)
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{
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    const GlobalProperty *prop = qdev_find_global_prop(dev, name);
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    if (!old_val) {
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        return true;
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    }
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    if (prop) {
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        error_setg(errp, "-global %s.%s=... conflicts with %s=%s",
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                   prop->driver, prop->property, name, new_val);
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						|
    } else {
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        /* Error message is vague, but a better one would be hard */
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        error_setg(errp, "%s=%s conflicts, and override is not implemented",
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                   name, new_val);
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    }
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    return false;
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}
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/* --- drive --- */
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static void get_drive(Object *obj, Visitor *v, const char *name, void *opaque,
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                      Error **errp)
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{
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    DeviceState *dev = DEVICE(obj);
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    Property *prop = opaque;
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    void **ptr = qdev_get_prop_ptr(dev, prop);
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    const char *value;
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    char *p;
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    if (*ptr) {
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        value = blk_name(*ptr);
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        if (!*value) {
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            BlockDriverState *bs = blk_bs(*ptr);
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						|
            if (bs) {
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                value = bdrv_get_node_name(bs);
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            }
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        }
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    } else {
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        value = "";
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    }
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    p = g_strdup(value);
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    visit_type_str(v, name, &p, errp);
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    g_free(p);
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}
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static void set_drive_helper(Object *obj, Visitor *v, const char *name,
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                             void *opaque, bool iothread, Error **errp)
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{
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    DeviceState *dev = DEVICE(obj);
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    Property *prop = opaque;
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    void **ptr = qdev_get_prop_ptr(dev, prop);
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    char *str;
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    BlockBackend *blk;
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    bool blk_created = false;
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    int ret;
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 | 
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    if (dev->realized) {
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        qdev_prop_set_after_realize(dev, name, errp);
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        return;
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    }
 | 
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 | 
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    if (!visit_type_str(v, name, &str, errp)) {
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        return;
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    }
 | 
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 | 
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    /*
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     * TODO Should this really be an error?  If no, the old value
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     * needs to be released before we store the new one.
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     */
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    if (!check_prop_still_unset(dev, name, *ptr, str, errp)) {
 | 
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        return;
 | 
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    }
 | 
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 | 
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    if (!*str) {
 | 
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        g_free(str);
 | 
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        *ptr = NULL;
 | 
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        return;
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    }
 | 
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 | 
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    blk = blk_by_name(str);
 | 
						|
    if (!blk) {
 | 
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        BlockDriverState *bs = bdrv_lookup_bs(NULL, str, NULL);
 | 
						|
        if (bs) {
 | 
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            /*
 | 
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             * If the device supports iothreads, it will make sure to move the
 | 
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             * block node to the right AioContext if necessary (or fail if this
 | 
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             * isn't possible because of other users). Devices that are not
 | 
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             * aware of iothreads require their BlockBackends to be in the main
 | 
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             * AioContext.
 | 
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             */
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            AioContext *ctx = iothread ? bdrv_get_aio_context(bs) :
 | 
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                                         qemu_get_aio_context();
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            blk = blk_new(ctx, 0, BLK_PERM_ALL);
 | 
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            blk_created = true;
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            ret = blk_insert_bs(blk, bs, errp);
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            if (ret < 0) {
 | 
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                goto fail;
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            }
 | 
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        }
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    }
 | 
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    if (!blk) {
 | 
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        error_setg(errp, "Property '%s.%s' can't find value '%s'",
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                   object_get_typename(OBJECT(dev)), prop->name, str);
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        goto fail;
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    }
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    if (blk_attach_dev(blk, dev) < 0) {
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        DriveInfo *dinfo = blk_legacy_dinfo(blk);
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        if (dinfo && dinfo->type != IF_NONE) {
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            error_setg(errp, "Drive '%s' is already in use because "
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                       "it has been automatically connected to another "
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                       "device (did you need 'if=none' in the drive options?)",
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                       str);
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        } else {
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            error_setg(errp, "Drive '%s' is already in use by another device",
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                       str);
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        }
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        goto fail;
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    }
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    *ptr = blk;
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fail:
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    if (blk_created) {
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        /* If we need to keep a reference, blk_attach_dev() took it */
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        blk_unref(blk);
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    }
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    g_free(str);
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}
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static void set_drive(Object *obj, Visitor *v, const char *name, void *opaque,
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                      Error **errp)
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{
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    set_drive_helper(obj, v, name, opaque, false, errp);
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}
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static void set_drive_iothread(Object *obj, Visitor *v, const char *name,
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                               void *opaque, Error **errp)
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{
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    set_drive_helper(obj, v, name, opaque, true, errp);
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}
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static void release_drive(Object *obj, const char *name, void *opaque)
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{
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    DeviceState *dev = DEVICE(obj);
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    Property *prop = opaque;
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    BlockBackend **ptr = qdev_get_prop_ptr(dev, prop);
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    if (*ptr) {
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        AioContext *ctx = blk_get_aio_context(*ptr);
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        aio_context_acquire(ctx);
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        blockdev_auto_del(*ptr);
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        blk_detach_dev(*ptr, dev);
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        aio_context_release(ctx);
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    }
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}
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const PropertyInfo qdev_prop_drive = {
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    .name  = "str",
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    .description = "Node name or ID of a block device to use as a backend",
 | 
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    .get   = get_drive,
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    .set   = set_drive,
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    .release = release_drive,
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};
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const PropertyInfo qdev_prop_drive_iothread = {
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    .name  = "str",
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    .description = "Node name or ID of a block device to use as a backend",
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    .get   = get_drive,
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    .set   = set_drive_iothread,
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    .release = release_drive,
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};
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/* --- character device --- */
 | 
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 | 
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static void get_chr(Object *obj, Visitor *v, const char *name, void *opaque,
 | 
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                    Error **errp)
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{
 | 
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    DeviceState *dev = DEVICE(obj);
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    CharBackend *be = qdev_get_prop_ptr(dev, opaque);
 | 
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    char *p;
 | 
						|
 | 
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    p = g_strdup(be->chr && be->chr->label ? be->chr->label : "");
 | 
						|
    visit_type_str(v, name, &p, errp);
 | 
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    g_free(p);
 | 
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}
 | 
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 | 
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static void set_chr(Object *obj, Visitor *v, const char *name, void *opaque,
 | 
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                    Error **errp)
 | 
						|
{
 | 
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    DeviceState *dev = DEVICE(obj);
 | 
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    Property *prop = opaque;
 | 
						|
    CharBackend *be = qdev_get_prop_ptr(dev, prop);
 | 
						|
    Chardev *s;
 | 
						|
    char *str;
 | 
						|
 | 
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    if (dev->realized) {
 | 
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        qdev_prop_set_after_realize(dev, name, errp);
 | 
						|
        return;
 | 
						|
    }
 | 
						|
 | 
						|
    if (!visit_type_str(v, name, &str, errp)) {
 | 
						|
        return;
 | 
						|
    }
 | 
						|
 | 
						|
    /*
 | 
						|
     * TODO Should this really be an error?  If no, the old value
 | 
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     * needs to be released before we store the new one.
 | 
						|
     */
 | 
						|
    if (!check_prop_still_unset(dev, name, be->chr, str, errp)) {
 | 
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        return;
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						|
    }
 | 
						|
 | 
						|
    if (!*str) {
 | 
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        g_free(str);
 | 
						|
        be->chr = NULL;
 | 
						|
        return;
 | 
						|
    }
 | 
						|
 | 
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    s = qemu_chr_find(str);
 | 
						|
    if (s == NULL) {
 | 
						|
        error_setg(errp, "Property '%s.%s' can't find value '%s'",
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                   object_get_typename(obj), prop->name, str);
 | 
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    } else if (!qemu_chr_fe_init(be, s, errp)) {
 | 
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        error_prepend(errp, "Property '%s.%s' can't take value '%s': ",
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                      object_get_typename(obj), prop->name, str);
 | 
						|
    }
 | 
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    g_free(str);
 | 
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}
 | 
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static void release_chr(Object *obj, const char *name, void *opaque)
 | 
						|
{
 | 
						|
    DeviceState *dev = DEVICE(obj);
 | 
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    Property *prop = opaque;
 | 
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    CharBackend *be = qdev_get_prop_ptr(dev, prop);
 | 
						|
 | 
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    qemu_chr_fe_deinit(be, false);
 | 
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}
 | 
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 | 
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const PropertyInfo qdev_prop_chr = {
 | 
						|
    .name  = "str",
 | 
						|
    .description = "ID of a chardev to use as a backend",
 | 
						|
    .get   = get_chr,
 | 
						|
    .set   = set_chr,
 | 
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    .release = release_chr,
 | 
						|
};
 | 
						|
 | 
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/* --- netdev device --- */
 | 
						|
static void get_netdev(Object *obj, Visitor *v, const char *name,
 | 
						|
                       void *opaque, Error **errp)
 | 
						|
{
 | 
						|
    DeviceState *dev = DEVICE(obj);
 | 
						|
    Property *prop = opaque;
 | 
						|
    NICPeers *peers_ptr = qdev_get_prop_ptr(dev, prop);
 | 
						|
    char *p = g_strdup(peers_ptr->ncs[0] ? peers_ptr->ncs[0]->name : "");
 | 
						|
 | 
						|
    visit_type_str(v, name, &p, errp);
 | 
						|
    g_free(p);
 | 
						|
}
 | 
						|
 | 
						|
static void set_netdev(Object *obj, Visitor *v, const char *name,
 | 
						|
                       void *opaque, Error **errp)
 | 
						|
{
 | 
						|
    DeviceState *dev = DEVICE(obj);
 | 
						|
    Property *prop = opaque;
 | 
						|
    NICPeers *peers_ptr = qdev_get_prop_ptr(dev, prop);
 | 
						|
    NetClientState **ncs = peers_ptr->ncs;
 | 
						|
    NetClientState *peers[MAX_QUEUE_NUM];
 | 
						|
    int queues, err = 0, i = 0;
 | 
						|
    char *str;
 | 
						|
 | 
						|
    if (dev->realized) {
 | 
						|
        qdev_prop_set_after_realize(dev, name, errp);
 | 
						|
        return;
 | 
						|
    }
 | 
						|
 | 
						|
    if (!visit_type_str(v, name, &str, errp)) {
 | 
						|
        return;
 | 
						|
    }
 | 
						|
 | 
						|
    queues = qemu_find_net_clients_except(str, peers,
 | 
						|
                                          NET_CLIENT_DRIVER_NIC,
 | 
						|
                                          MAX_QUEUE_NUM);
 | 
						|
    if (queues == 0) {
 | 
						|
        err = -ENOENT;
 | 
						|
        goto out;
 | 
						|
    }
 | 
						|
 | 
						|
    if (queues > MAX_QUEUE_NUM) {
 | 
						|
        error_setg(errp, "queues of backend '%s'(%d) exceeds QEMU limitation(%d)",
 | 
						|
                   str, queues, MAX_QUEUE_NUM);
 | 
						|
        goto out;
 | 
						|
    }
 | 
						|
 | 
						|
    for (i = 0; i < queues; i++) {
 | 
						|
        if (peers[i]->peer) {
 | 
						|
            err = -EEXIST;
 | 
						|
            goto out;
 | 
						|
        }
 | 
						|
 | 
						|
        /*
 | 
						|
         * TODO Should this really be an error?  If no, the old value
 | 
						|
         * needs to be released before we store the new one.
 | 
						|
         */
 | 
						|
        if (!check_prop_still_unset(dev, name, ncs[i], str, errp)) {
 | 
						|
            goto out;
 | 
						|
        }
 | 
						|
 | 
						|
        ncs[i] = peers[i];
 | 
						|
        ncs[i]->queue_index = i;
 | 
						|
    }
 | 
						|
 | 
						|
    peers_ptr->queues = queues;
 | 
						|
 | 
						|
out:
 | 
						|
    error_set_from_qdev_prop_error(errp, err, dev, prop, str);
 | 
						|
    g_free(str);
 | 
						|
}
 | 
						|
 | 
						|
const PropertyInfo qdev_prop_netdev = {
 | 
						|
    .name  = "str",
 | 
						|
    .description = "ID of a netdev to use as a backend",
 | 
						|
    .get   = get_netdev,
 | 
						|
    .set   = set_netdev,
 | 
						|
};
 | 
						|
 | 
						|
 | 
						|
/* --- audiodev --- */
 | 
						|
static void get_audiodev(Object *obj, Visitor *v, const char* name,
 | 
						|
                         void *opaque, Error **errp)
 | 
						|
{
 | 
						|
    DeviceState *dev = DEVICE(obj);
 | 
						|
    Property *prop = opaque;
 | 
						|
    QEMUSoundCard *card = qdev_get_prop_ptr(dev, prop);
 | 
						|
    char *p = g_strdup(audio_get_id(card));
 | 
						|
 | 
						|
    visit_type_str(v, name, &p, errp);
 | 
						|
    g_free(p);
 | 
						|
}
 | 
						|
 | 
						|
static void set_audiodev(Object *obj, Visitor *v, const char* name,
 | 
						|
                         void *opaque, Error **errp)
 | 
						|
{
 | 
						|
    DeviceState *dev = DEVICE(obj);
 | 
						|
    Property *prop = opaque;
 | 
						|
    QEMUSoundCard *card = qdev_get_prop_ptr(dev, prop);
 | 
						|
    AudioState *state;
 | 
						|
    int err = 0;
 | 
						|
    char *str;
 | 
						|
 | 
						|
    if (dev->realized) {
 | 
						|
        qdev_prop_set_after_realize(dev, name, errp);
 | 
						|
        return;
 | 
						|
    }
 | 
						|
 | 
						|
    if (!visit_type_str(v, name, &str, errp)) {
 | 
						|
        return;
 | 
						|
    }
 | 
						|
 | 
						|
    state = audio_state_by_name(str);
 | 
						|
 | 
						|
    if (!state) {
 | 
						|
        err = -ENOENT;
 | 
						|
        goto out;
 | 
						|
    }
 | 
						|
    card->state = state;
 | 
						|
 | 
						|
out:
 | 
						|
    error_set_from_qdev_prop_error(errp, err, dev, prop, str);
 | 
						|
    g_free(str);
 | 
						|
}
 | 
						|
 | 
						|
const PropertyInfo qdev_prop_audiodev = {
 | 
						|
    .name = "str",
 | 
						|
    .description = "ID of an audiodev to use as a backend",
 | 
						|
    /* release done on shutdown */
 | 
						|
    .get = get_audiodev,
 | 
						|
    .set = set_audiodev,
 | 
						|
};
 | 
						|
 | 
						|
bool qdev_prop_set_drive_err(DeviceState *dev, const char *name,
 | 
						|
                             BlockBackend *value, Error **errp)
 | 
						|
{
 | 
						|
    const char *ref = "";
 | 
						|
 | 
						|
    if (value) {
 | 
						|
        ref = blk_name(value);
 | 
						|
        if (!*ref) {
 | 
						|
            const BlockDriverState *bs = blk_bs(value);
 | 
						|
            if (bs) {
 | 
						|
                ref = bdrv_get_node_name(bs);
 | 
						|
            }
 | 
						|
        }
 | 
						|
    }
 | 
						|
 | 
						|
    return object_property_set_str(OBJECT(dev), name, ref, errp);
 | 
						|
}
 | 
						|
 | 
						|
void qdev_prop_set_drive(DeviceState *dev, const char *name,
 | 
						|
                         BlockBackend *value)
 | 
						|
{
 | 
						|
    qdev_prop_set_drive_err(dev, name, value, &error_abort);
 | 
						|
}
 | 
						|
 | 
						|
void qdev_prop_set_chr(DeviceState *dev, const char *name,
 | 
						|
                       Chardev *value)
 | 
						|
{
 | 
						|
    assert(!value || value->label);
 | 
						|
    object_property_set_str(OBJECT(dev), name, value ? value->label : "",
 | 
						|
                            &error_abort);
 | 
						|
}
 | 
						|
 | 
						|
void qdev_prop_set_netdev(DeviceState *dev, const char *name,
 | 
						|
                          NetClientState *value)
 | 
						|
{
 | 
						|
    assert(!value || value->name);
 | 
						|
    object_property_set_str(OBJECT(dev), name, value ? value->name : "",
 | 
						|
                            &error_abort);
 | 
						|
}
 | 
						|
 | 
						|
void qdev_set_nic_properties(DeviceState *dev, NICInfo *nd)
 | 
						|
{
 | 
						|
    qdev_prop_set_macaddr(dev, "mac", nd->macaddr.a);
 | 
						|
    if (nd->netdev) {
 | 
						|
        qdev_prop_set_netdev(dev, "netdev", nd->netdev);
 | 
						|
    }
 | 
						|
    if (nd->nvectors != DEV_NVECTORS_UNSPECIFIED &&
 | 
						|
        object_property_find(OBJECT(dev), "vectors", NULL)) {
 | 
						|
        qdev_prop_set_uint32(dev, "vectors", nd->nvectors);
 | 
						|
    }
 | 
						|
    nd->instantiated = 1;
 | 
						|
}
 |