Message ID | 20221213213757.4123265-3-fasano@mit.edu |
---|---|
State | New |
Headers | show |
Series | Inter-plugin interactions with QPP | expand |
Andrew Fasano <fasano@mit.edu> writes: > From: Elysia Witham <elysia.witham@ll.mit.edu> > > In order for the QPP API to resolve interactions between plugins, > plugins must export their own names which cannot match any other > loaded plugins. > > Signed-off-by: Elysia Witham <elysia.witham@ll.mit.edu> > Signed-off-by: Andrew Fasano <fasano@mit.edu> > --- > include/qemu/qemu-plugin.h | 2 +- > plugins/core.c | 12 +++++++++ > plugins/loader.c | 50 +++++++++++++++++++++++++++++++++----- > plugins/plugin.h | 7 ++++++ > tests/plugin/bb.c | 1 + > tests/plugin/empty.c | 1 + > tests/plugin/insn.c | 1 + > tests/plugin/mem.c | 1 + > tests/plugin/syscall.c | 1 + > 9 files changed, 69 insertions(+), 7 deletions(-) > > diff --git a/include/qemu/qemu-plugin.h b/include/qemu/qemu-plugin.h > index d0e9d03adf..5326f33ce8 100644 > --- a/include/qemu/qemu-plugin.h > +++ b/include/qemu/qemu-plugin.h > @@ -51,7 +51,7 @@ typedef uint64_t qemu_plugin_id_t; > > extern QEMU_PLUGIN_EXPORT int qemu_plugin_version; > > -#define QEMU_PLUGIN_VERSION 1 > +#define QEMU_PLUGIN_VERSION 2 > > /** > * struct qemu_info_t - system information for plugins > diff --git a/plugins/core.c b/plugins/core.c > index ccb770a485..5fbdcb5768 100644 > --- a/plugins/core.c > +++ b/plugins/core.c > @@ -236,6 +236,18 @@ void qemu_plugin_vcpu_exit_hook(CPUState *cpu) > qemu_rec_mutex_unlock(&plugin.lock); > } > > +int name_to_plugin_version(const char *name) > +{ > + struct qemu_plugin_ctx *ctx; > + QTAILQ_FOREACH(ctx, &plugin.ctxs, entry) { > + if (strcmp(ctx->name, name) == 0) { > + return ctx->version; > + } > + } > + warn_report("Could not find any plugin named %s.", name); > + return -1; > +} > + This function seems to be unused. > struct plugin_for_each_args { > struct qemu_plugin_ctx *ctx; > qemu_plugin_vcpu_simple_cb_t cb; > diff --git a/plugins/loader.c b/plugins/loader.c > index 88c30bde2d..12c0680e03 100644 > --- a/plugins/loader.c > +++ b/plugins/loader.c > @@ -177,7 +177,7 @@ QEMU_DISABLE_CFI > static int plugin_load(struct qemu_plugin_desc *desc, const qemu_info_t *info, Error **errp) > { > qemu_plugin_install_func_t install; > - struct qemu_plugin_ctx *ctx; > + struct qemu_plugin_ctx *ctx, *ctx2; > gpointer sym; > int rc; > > @@ -208,17 +208,55 @@ static int plugin_load(struct qemu_plugin_desc *desc, const qemu_info_t *info, E > desc->path, g_module_error()); > goto err_symbol; > } else { > - int version = *(int *)sym; > - if (version < QEMU_PLUGIN_MIN_VERSION) { > + ctx->version = *(int *)sym; > + if (ctx->version < QEMU_PLUGIN_MIN_VERSION) { > error_setg(errp, "Could not load plugin %s: plugin requires API version %d, but " > "this QEMU supports only a minimum version of %d", > - desc->path, version, QEMU_PLUGIN_MIN_VERSION); > + desc->path, ctx->version, QEMU_PLUGIN_MIN_VERSION); > goto err_symbol; > - } else if (version > QEMU_PLUGIN_VERSION) { > + } else if (ctx->version > QEMU_PLUGIN_VERSION) { > error_setg(errp, "Could not load plugin %s: plugin requires API version %d, but " > "this QEMU supports only up to version %d", > - desc->path, version, QEMU_PLUGIN_VERSION); > + desc->path, ctx->version, QEMU_PLUGIN_VERSION); > goto err_symbol; > + } else if (ctx->version < QPP_MINIMUM_VERSION) { > + ctx->name = NULL; A comment wouldn't go amiss here. Something like: "Older plugins will not be available for QPP calls". > + } else { > + if (!g_module_symbol(ctx->handle, "qemu_plugin_name", &sym)) { > + error_setg(errp, "Could not load plugin %s: plugin does not " > + "declare plugin name %s", > + desc->path, g_module_error()); > + goto err_symbol; > + } > + ctx->name = (const char *)strdup(*(const char **)sym); > + QTAILQ_FOREACH(ctx2, &plugin.ctxs, entry) { > + if (strcmp(ctx2->name, ctx->name) == 0) { > + error_setg(errp, "Could not load plugin %s as the name %s " > + "is already in use by plugin at %s", > + desc->path, ctx->name, ctx2->desc->path); > + goto err_symbol; > + } > + } > + if (g_module_symbol(ctx->handle, "qemu_plugin_uses", &sym)) { > + const char **dependencies = &(*(const char **)sym); > + bool found = false; > + while (*dependencies) { > + found = false; > + QTAILQ_FOREACH(ctx2, &plugin.ctxs, entry) { > + if (strcmp(ctx2->name, *dependencies) == 0) { Lets use glib where we can, in this case g_strcmp0(). > + dependencies++; > + found = true; > + break; > + } > + } > + if (!found) { > + error_setg(errp, "Could not load plugin %s as it is " > + "dependent on %s which is not loaded", > + ctx->name, *dependencies); > + goto err_symbol; > + } We are implying a load order here which we should document. Ideally we could avoid it but I suspect that requires too much hoop jumping. > + } > + } > } > } > > diff --git a/plugins/plugin.h b/plugins/plugin.h > index 5eb2fdbc85..ce885bfa98 100644 > --- a/plugins/plugin.h > +++ b/plugins/plugin.h > @@ -16,6 +16,7 @@ > #include "qemu/qht.h" > > #define QEMU_PLUGIN_MIN_VERSION 0 > +#define QPP_MINIMUM_VERSION 2 > > /* global state */ > struct qemu_plugin_state { > @@ -50,6 +51,8 @@ struct qemu_plugin_state { > struct qemu_plugin_ctx { > GModule *handle; > qemu_plugin_id_t id; > + const char *name; > + int version; > struct qemu_plugin_cb *callbacks[QEMU_PLUGIN_EV_MAX]; > QTAILQ_ENTRY(qemu_plugin_ctx) entry; > /* > @@ -64,6 +67,8 @@ struct qemu_plugin_ctx { > > struct qemu_plugin_ctx *plugin_id_to_ctx_locked(qemu_plugin_id_t id); > > +struct qemu_plugin_ctx *plugin_name_to_ctx_locked(const char* name); > + > void plugin_register_inline_op(GArray **arr, > enum qemu_plugin_mem_rw rw, > enum qemu_plugin_op op, void *ptr, > @@ -97,4 +102,6 @@ void plugin_register_vcpu_mem_cb(GArray **arr, > > void exec_inline_op(struct qemu_plugin_dyn_cb *cb); > > +int name_to_plugin_version(const char *name); > + > #endif /* PLUGIN_H */ > diff --git a/tests/plugin/bb.c b/tests/plugin/bb.c > index 7d470a1011..c04e5aaf90 100644 > --- a/tests/plugin/bb.c > +++ b/tests/plugin/bb.c > @@ -15,6 +15,7 @@ > #include <qemu-plugin.h> > > QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION; > +QEMU_PLUGIN_EXPORT const char *qemu_plugin_name = "bb"; > > typedef struct { > GMutex lock; > diff --git a/tests/plugin/empty.c b/tests/plugin/empty.c > index 8fa6bacd93..0f3d2b92b9 100644 > --- a/tests/plugin/empty.c > +++ b/tests/plugin/empty.c > @@ -14,6 +14,7 @@ > #include <qemu-plugin.h> > > QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION; > +QEMU_PLUGIN_EXPORT const char *qemu_plugin_name = "empty"; > > /* > * Empty TB translation callback. > diff --git a/tests/plugin/insn.c b/tests/plugin/insn.c > index cd5ea5d4ae..3f71138139 100644 > --- a/tests/plugin/insn.c > +++ b/tests/plugin/insn.c > @@ -15,6 +15,7 @@ > #include <qemu-plugin.h> > > QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION; > +QEMU_PLUGIN_EXPORT const char *qemu_plugin_name = "insn"; > > #define MAX_CPUS 8 /* lets not go nuts */ > > diff --git a/tests/plugin/mem.c b/tests/plugin/mem.c > index 4570f7d815..35e5d7fe2a 100644 > --- a/tests/plugin/mem.c > +++ b/tests/plugin/mem.c > @@ -15,6 +15,7 @@ > #include <qemu-plugin.h> > > QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION; > +QEMU_PLUGIN_EXPORT const char *qemu_plugin_name = "mem"; > > static uint64_t inline_mem_count; > static uint64_t cb_mem_count; > diff --git a/tests/plugin/syscall.c b/tests/plugin/syscall.c > index 96040c578f..922bdbd2e6 100644 > --- a/tests/plugin/syscall.c > +++ b/tests/plugin/syscall.c > @@ -15,6 +15,7 @@ > #include <qemu-plugin.h> > > QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION; > +QEMU_PLUGIN_EXPORT const char *qemu_plugin_name = "syscall"; > > typedef struct { > int64_t num; You should update the plugins in contrib/plugins as well.
diff --git a/include/qemu/qemu-plugin.h b/include/qemu/qemu-plugin.h index d0e9d03adf..5326f33ce8 100644 --- a/include/qemu/qemu-plugin.h +++ b/include/qemu/qemu-plugin.h @@ -51,7 +51,7 @@ typedef uint64_t qemu_plugin_id_t; extern QEMU_PLUGIN_EXPORT int qemu_plugin_version; -#define QEMU_PLUGIN_VERSION 1 +#define QEMU_PLUGIN_VERSION 2 /** * struct qemu_info_t - system information for plugins diff --git a/plugins/core.c b/plugins/core.c index ccb770a485..5fbdcb5768 100644 --- a/plugins/core.c +++ b/plugins/core.c @@ -236,6 +236,18 @@ void qemu_plugin_vcpu_exit_hook(CPUState *cpu) qemu_rec_mutex_unlock(&plugin.lock); } +int name_to_plugin_version(const char *name) +{ + struct qemu_plugin_ctx *ctx; + QTAILQ_FOREACH(ctx, &plugin.ctxs, entry) { + if (strcmp(ctx->name, name) == 0) { + return ctx->version; + } + } + warn_report("Could not find any plugin named %s.", name); + return -1; +} + struct plugin_for_each_args { struct qemu_plugin_ctx *ctx; qemu_plugin_vcpu_simple_cb_t cb; diff --git a/plugins/loader.c b/plugins/loader.c index 88c30bde2d..12c0680e03 100644 --- a/plugins/loader.c +++ b/plugins/loader.c @@ -177,7 +177,7 @@ QEMU_DISABLE_CFI static int plugin_load(struct qemu_plugin_desc *desc, const qemu_info_t *info, Error **errp) { qemu_plugin_install_func_t install; - struct qemu_plugin_ctx *ctx; + struct qemu_plugin_ctx *ctx, *ctx2; gpointer sym; int rc; @@ -208,17 +208,55 @@ static int plugin_load(struct qemu_plugin_desc *desc, const qemu_info_t *info, E desc->path, g_module_error()); goto err_symbol; } else { - int version = *(int *)sym; - if (version < QEMU_PLUGIN_MIN_VERSION) { + ctx->version = *(int *)sym; + if (ctx->version < QEMU_PLUGIN_MIN_VERSION) { error_setg(errp, "Could not load plugin %s: plugin requires API version %d, but " "this QEMU supports only a minimum version of %d", - desc->path, version, QEMU_PLUGIN_MIN_VERSION); + desc->path, ctx->version, QEMU_PLUGIN_MIN_VERSION); goto err_symbol; - } else if (version > QEMU_PLUGIN_VERSION) { + } else if (ctx->version > QEMU_PLUGIN_VERSION) { error_setg(errp, "Could not load plugin %s: plugin requires API version %d, but " "this QEMU supports only up to version %d", - desc->path, version, QEMU_PLUGIN_VERSION); + desc->path, ctx->version, QEMU_PLUGIN_VERSION); goto err_symbol; + } else if (ctx->version < QPP_MINIMUM_VERSION) { + ctx->name = NULL; + } else { + if (!g_module_symbol(ctx->handle, "qemu_plugin_name", &sym)) { + error_setg(errp, "Could not load plugin %s: plugin does not " + "declare plugin name %s", + desc->path, g_module_error()); + goto err_symbol; + } + ctx->name = (const char *)strdup(*(const char **)sym); + QTAILQ_FOREACH(ctx2, &plugin.ctxs, entry) { + if (strcmp(ctx2->name, ctx->name) == 0) { + error_setg(errp, "Could not load plugin %s as the name %s " + "is already in use by plugin at %s", + desc->path, ctx->name, ctx2->desc->path); + goto err_symbol; + } + } + if (g_module_symbol(ctx->handle, "qemu_plugin_uses", &sym)) { + const char **dependencies = &(*(const char **)sym); + bool found = false; + while (*dependencies) { + found = false; + QTAILQ_FOREACH(ctx2, &plugin.ctxs, entry) { + if (strcmp(ctx2->name, *dependencies) == 0) { + dependencies++; + found = true; + break; + } + } + if (!found) { + error_setg(errp, "Could not load plugin %s as it is " + "dependent on %s which is not loaded", + ctx->name, *dependencies); + goto err_symbol; + } + } + } } } diff --git a/plugins/plugin.h b/plugins/plugin.h index 5eb2fdbc85..ce885bfa98 100644 --- a/plugins/plugin.h +++ b/plugins/plugin.h @@ -16,6 +16,7 @@ #include "qemu/qht.h" #define QEMU_PLUGIN_MIN_VERSION 0 +#define QPP_MINIMUM_VERSION 2 /* global state */ struct qemu_plugin_state { @@ -50,6 +51,8 @@ struct qemu_plugin_state { struct qemu_plugin_ctx { GModule *handle; qemu_plugin_id_t id; + const char *name; + int version; struct qemu_plugin_cb *callbacks[QEMU_PLUGIN_EV_MAX]; QTAILQ_ENTRY(qemu_plugin_ctx) entry; /* @@ -64,6 +67,8 @@ struct qemu_plugin_ctx { struct qemu_plugin_ctx *plugin_id_to_ctx_locked(qemu_plugin_id_t id); +struct qemu_plugin_ctx *plugin_name_to_ctx_locked(const char* name); + void plugin_register_inline_op(GArray **arr, enum qemu_plugin_mem_rw rw, enum qemu_plugin_op op, void *ptr, @@ -97,4 +102,6 @@ void plugin_register_vcpu_mem_cb(GArray **arr, void exec_inline_op(struct qemu_plugin_dyn_cb *cb); +int name_to_plugin_version(const char *name); + #endif /* PLUGIN_H */ diff --git a/tests/plugin/bb.c b/tests/plugin/bb.c index 7d470a1011..c04e5aaf90 100644 --- a/tests/plugin/bb.c +++ b/tests/plugin/bb.c @@ -15,6 +15,7 @@ #include <qemu-plugin.h> QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION; +QEMU_PLUGIN_EXPORT const char *qemu_plugin_name = "bb"; typedef struct { GMutex lock; diff --git a/tests/plugin/empty.c b/tests/plugin/empty.c index 8fa6bacd93..0f3d2b92b9 100644 --- a/tests/plugin/empty.c +++ b/tests/plugin/empty.c @@ -14,6 +14,7 @@ #include <qemu-plugin.h> QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION; +QEMU_PLUGIN_EXPORT const char *qemu_plugin_name = "empty"; /* * Empty TB translation callback. diff --git a/tests/plugin/insn.c b/tests/plugin/insn.c index cd5ea5d4ae..3f71138139 100644 --- a/tests/plugin/insn.c +++ b/tests/plugin/insn.c @@ -15,6 +15,7 @@ #include <qemu-plugin.h> QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION; +QEMU_PLUGIN_EXPORT const char *qemu_plugin_name = "insn"; #define MAX_CPUS 8 /* lets not go nuts */ diff --git a/tests/plugin/mem.c b/tests/plugin/mem.c index 4570f7d815..35e5d7fe2a 100644 --- a/tests/plugin/mem.c +++ b/tests/plugin/mem.c @@ -15,6 +15,7 @@ #include <qemu-plugin.h> QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION; +QEMU_PLUGIN_EXPORT const char *qemu_plugin_name = "mem"; static uint64_t inline_mem_count; static uint64_t cb_mem_count; diff --git a/tests/plugin/syscall.c b/tests/plugin/syscall.c index 96040c578f..922bdbd2e6 100644 --- a/tests/plugin/syscall.c +++ b/tests/plugin/syscall.c @@ -15,6 +15,7 @@ #include <qemu-plugin.h> QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION; +QEMU_PLUGIN_EXPORT const char *qemu_plugin_name = "syscall"; typedef struct { int64_t num;