ioq: Implement ioq_stat()

3 files changed, 124 insertions, 10 deletions

diff --git a/src/bftw.c b/src/bftw.c
index 952b090..02dd051 100644
--- a/src/bftw.c
+++ b/src/bftw.c
@@ -631,6 +631,9 @@ static int bftw_ioq_pop(struct bftw_state *state, bool block) {
 			SLIST_APPEND(&state->to_read, file, to_read);
 		}
 		break;
+
+	case IOQ_STAT:
+		break;
 	}
 
 	ioq_free(ioq, ent);
diff --git a/src/ioq.c b/src/ioq.c
index 3d32dfe..3172f0a 100644
--- a/src/ioq.c
+++ b/src/ioq.c
@@ -131,6 +131,7 @@
 #include "diag.h"
 #include "dir.h"
 #include "sanity.h"
+#include "stat.h"
 #include "thread.h"
 #include <assert.h>
 #include <errno.h>
@@ -432,6 +433,10 @@ struct ioq {
 
 	/** ioq_ent arena. */
 	struct arena ents;
+#if BFS_USE_LIBURING && BFS_USE_STATX
+	/** struct statx arena. */
+	struct arena xbufs;
+#endif
 
 	/** Pending I/O requests. */
 	struct ioqq *pending;
@@ -479,6 +484,12 @@ static void ioq_dispatch_sync(struct ioq *ioq, struct ioq_ent *ent) {
 		case IOQ_CLOSEDIR:
 			ent->result = try(bfs_closedir(ent->closedir.dir));
 			return;
+
+		case IOQ_STAT: {
+			struct ioq_stat *args = &ent->stat;
+			ent->result = try(bfs_stat(args->dfd, args->path, args->flags, args->buf));
+			return;
+		}
 	}
 
 	bfs_bug("Unknown ioq_op %d", (int)ent->op);
@@ -549,6 +560,17 @@ static struct io_uring_sqe *ioq_dispatch_async(struct io_uring *ring, struct ioq
 			io_uring_prep_close(sqe, bfs_unwrapdir(ent->closedir.dir));
 #endif
 			return sqe;
+
+		case IOQ_STAT: {
+#if BFS_USE_STATX
+			sqe = io_uring_get_sqe(ring);
+			struct ioq_stat *args = &ent->stat;
+			int flags = bfs_statx_flags(args->flags);
+			unsigned int mask = STATX_BASIC_STATS | STATX_BTIME;
+			io_uring_prep_statx(sqe, args->dfd, args->path, flags, mask, args->xbuf);
+#endif
+			return sqe;
+		}
 	}
 
 	bfs_bug("Unknown ioq_op %d", (int)ent->op);
@@ -597,21 +619,41 @@ static void ioq_reap_cqe(struct ioq_ring_state *state, struct io_uring_cqe *cqe)
 	io_uring_cqe_seen(ring, cqe);
 	--state->submitted;
 
-	if (ent->op == IOQ_OPENDIR && ent->result >= 0) {
-		int fd = ent->result;
-		if (ioq_check_cancel(ioq, ent)) {
-			xclose(fd);
-			return;
+	if (ent->result < 0) {
+		goto push;
+	}
+
+	switch (ent->op) {
+		case IOQ_OPENDIR: {
+			int fd = ent->result;
+			if (ioq_check_cancel(ioq, ent)) {
+				xclose(fd);
+				return;
+			}
+
+			struct ioq_opendir *args = &ent->opendir;
+			ent->result = try(bfs_opendir(args->dir, fd, NULL, args->flags));
+			if (ent->result >= 0) {
+				// TODO: io_uring_prep_getdents()
+				bfs_polldir(args->dir);
+			}
+
+			break;
 		}
 
-		struct ioq_opendir *args = &ent->opendir;
-		ent->result = try(bfs_opendir(args->dir, fd, NULL, args->flags));
-		if (ent->result >= 0) {
-			// TODO: io_uring_prep_getdents()
-			bfs_polldir(args->dir);
+#if BFS_USE_STATX
+		case IOQ_STAT: {
+			struct ioq_stat *args = &ent->stat;
+			ent->result = try(bfs_statx_convert(args->buf, args->xbuf));
+			break;
 		}
+#endif
+
+		default:
+			break;
 	}
 
+push:
 	ioqq_push(ioq->ready, ent);
 }
 
@@ -689,8 +731,13 @@ struct ioq *ioq_create(size_t depth, size_t nthreads) {
 	}
 
 	ioq->depth = depth;
+
 	ARENA_INIT(&ioq->ents, struct ioq_ent);
 
+#if BFS_USE_LIBURING && BFS_USE_STATX
+	ARENA_INIT(&ioq->xbufs, struct statx);
+#endif
+
 	ioq->pending = ioqq_create(depth);
 	if (!ioq->pending) {
 		goto fail;
@@ -807,6 +854,30 @@ int ioq_closedir(struct ioq *ioq, struct bfs_dir *dir, void *ptr) {
 	return 0;
 }
 
+int ioq_stat(struct ioq *ioq, int dfd, const char *path, enum bfs_stat_flags flags, struct bfs_stat *buf, void *ptr) {
+	struct ioq_ent *ent = ioq_request(ioq, IOQ_STAT, ptr);
+	if (!ent) {
+		return -1;
+	}
+
+	struct ioq_stat *args = &ent->stat;
+	args->dfd = dfd;
+	args->path = path;
+	args->flags = flags;
+	args->buf = buf;
+
+#if BFS_USE_LIBURING && BFS_USE_STATX
+	args->xbuf = arena_alloc(&ioq->xbufs);
+	if (!args->xbuf) {
+		ioq_free(ioq, ent);
+		return -1;
+	}
+#endif
+
+	ioqq_push(ioq->pending, ent);
+	return 0;
+}
+
 struct ioq_ent *ioq_pop(struct ioq *ioq, bool block) {
 	if (ioq->size == 0) {
 		return NULL;
@@ -819,6 +890,12 @@ void ioq_free(struct ioq *ioq, struct ioq_ent *ent) {
 	bfs_assert(ioq->size > 0);
 	--ioq->size;
 
+#if BFS_USE_LIBURING && BFS_USE_STATX
+	if (ent->op == IOQ_STAT) {
+		arena_free(&ioq->xbufs, ent->stat.xbuf);
+	}
+#endif
+
 	arena_free(&ioq->ents, ent);
 }
 
@@ -848,6 +925,9 @@ void ioq_destroy(struct ioq *ioq) {
 	ioqq_destroy(ioq->ready);
 	ioqq_destroy(ioq->pending);
 
+#if BFS_USE_LIBURING && BFS_USE_STATX
+	arena_destroy(&ioq->xbufs);
+#endif
 	arena_destroy(&ioq->ents);
 
 	free(ioq);
diff --git a/src/ioq.h b/src/ioq.h
index e1e5052..77aabaa 100644
--- a/src/ioq.h
+++ b/src/ioq.h
@@ -10,6 +10,7 @@
 
 #include "config.h"
 #include "dir.h"
+#include "stat.h"
 #include <stddef.h>
 
 /**
@@ -27,6 +28,8 @@ enum ioq_op {
 	IOQ_OPENDIR,
 	/** ioq_closedir(). */
 	IOQ_CLOSEDIR,
+	/** ioq_stat(). */
+	IOQ_STAT,
 };
 
 /**
@@ -59,6 +62,14 @@ struct ioq_ent {
 		struct ioq_closedir {
 			struct bfs_dir *dir;
 		} closedir;
+		/** ioq_stat() args. */
+		struct ioq_stat {
+			int dfd;
+			const char *path;
+			enum bfs_stat_flags flags;
+			struct bfs_stat *buf;
+			void *xbuf;
+		} stat;
 	};
 };
 
@@ -128,6 +139,26 @@ int ioq_opendir(struct ioq *ioq, struct bfs_dir *dir, int dfd, const char *path,
 int ioq_closedir(struct ioq *ioq, struct bfs_dir *dir, void *ptr);
 
 /**
+ * Asynchronous bfs_stat().
+ *
+ * @param ioq
+ *         The I/O queue.
+ * @param dfd
+ *         The base file descriptor.
+ * @param path
+ *         The path to stat, relative to dfd.
+ * @param flags
+ *         Flags that affect the lookup.
+ * @param buf
+ *         A place to store the stat buffer, if successful.
+ * @param ptr
+ *         An arbitrary pointer to associate with the request.
+ * @return
+ *         0 on success, or -1 on failure.
+ */
+int ioq_stat(struct ioq *ioq, int dfd, const char *path, enum bfs_stat_flags flags, struct bfs_stat *buf, void *ptr);
+
+/**
  * Pop a response from the queue.
  *
  * @param ioq