1 files changed, 164 insertions, 0 deletions
diff --git a/src/pmdk/src/libpmem2/extent_linux.c b/src/pmdk/src/libpmem2/extent_linux.c
new file mode 100644
index 000000000..6491e67b6
--- /dev/null
+++ b/src/pmdk/src/libpmem2/extent_linux.c
@@ -0,0 +1,164 @@
+// SPDX-License-Identifier: BSD-3-Clause
+/* Copyright 2018-2020, Intel Corporation */
+
+/*
+ * extent_linux.c - implementation of the linux fs extent query API
+ */
+
+#include <string.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <linux/fs.h>
+#include <linux/fiemap.h>
+
+#include "libpmem2.h"
+#include "pmem2_utils.h"
+
+#include "file.h"
+#include "out.h"
+#include "extent.h"
+#include "alloc.h"
+
+/*
+ * pmem2_extents_create_get -- allocate extents structure and get extents
+ *                             of the given file
+ */
+int
+pmem2_extents_create_get(int fd, struct extents **exts)
+{
+	LOG(3, "fd %i extents %p", fd, exts);
+
+	ASSERT(fd > 2);
+	ASSERTne(exts, NULL);
+
+	enum pmem2_file_type pmem2_type;
+	struct extents *pexts = NULL;
+	struct fiemap *fmap = NULL;
+	os_stat_t st;
+
+	if (os_fstat(fd, &st) < 0) {
+		ERR("!fstat %d", fd);
+		return PMEM2_E_ERRNO;
+	}
+
+	int ret = pmem2_get_type_from_stat(&st, &pmem2_type);
+	if (ret)
+		return ret;
+
+	/* directories do not have any extents */
+	if (pmem2_type == PMEM2_FTYPE_DIR) {
+		ERR(
+			"checking extents does not make sense in case of directories");
+		return PMEM2_E_INVALID_FILE_TYPE;
+	}
+
+	/* allocate extents structure */
+	pexts = pmem2_zalloc(sizeof(struct extents), &ret);
+	if (ret)
+		return ret;
+
+	/* save block size */
+	LOG(10, "fd %i: block size: %li", fd, (long int)st.st_blksize);
+	pexts->blksize = (uint64_t)st.st_blksize;
+
+	/* DAX device does not have any extents */
+	if (pmem2_type == PMEM2_FTYPE_DEVDAX) {
+		*exts = pexts;
+		return 0;
+	}
+
+	ASSERTeq(pmem2_type, PMEM2_FTYPE_REG);
+
+	fmap = pmem2_zalloc(sizeof(struct fiemap), &ret);
+	if (ret)
+		goto error_free;
+
+	fmap->fm_start = 0;
+	fmap->fm_length = (size_t)st.st_size;
+	fmap->fm_flags = 0;
+	fmap->fm_extent_count = 0;
+	fmap->fm_mapped_extents = 0;
+
+	if (ioctl(fd, FS_IOC_FIEMAP, fmap) != 0) {
+		ERR("!fiemap ioctl() for fd=%d failed", fd);
+		ret = PMEM2_E_ERRNO;
+		goto error_free;
+	}
+
+	size_t newsize = sizeof(struct fiemap) +
+		fmap->fm_mapped_extents * sizeof(struct fiemap_extent);
+
+	struct fiemap *newfmap = pmem2_realloc(fmap, newsize, &ret);
+	if (ret)
+		goto error_free;
+
+	fmap = newfmap;
+	memset(fmap->fm_extents, 0, fmap->fm_mapped_extents *
+					sizeof(struct fiemap_extent));
+	fmap->fm_extent_count = fmap->fm_mapped_extents;
+	fmap->fm_mapped_extents = 0;
+
+	if (ioctl(fd, FS_IOC_FIEMAP, fmap) != 0) {
+		ERR("!fiemap ioctl() for fd=%d failed", fd);
+		ret = PMEM2_E_ERRNO;
+		goto error_free;
+	}
+
+	LOG(4, "file with fd=%i has %u extents:", fd, fmap->fm_mapped_extents);
+
+	/* save number of extents */
+	pexts->extents_count = fmap->fm_mapped_extents;
+
+	pexts->extents = pmem2_malloc(
+				pexts->extents_count * sizeof(struct extent),
+				&ret);
+	if (ret)
+		goto error_free;
+
+	/* save extents */
+	unsigned e;
+	for (e = 0; e < fmap->fm_mapped_extents; e++) {
+		pexts->extents[e].offset_physical =
+			fmap->fm_extents[e].fe_physical;
+		pexts->extents[e].offset_logical =
+			fmap->fm_extents[e].fe_logical;
+		pexts->extents[e].length =
+			fmap->fm_extents[e].fe_length;
+
+		LOG(10, "   #%u: off_phy: %lu off_log: %lu len: %lu",
+			e,
+			pexts->extents[e].offset_physical,
+			pexts->extents[e].offset_logical,
+			pexts->extents[e].length);
+	}
+
+	*exts = pexts;
+
+	Free(fmap);
+
+	return 0;
+
+error_free:
+	Free(pexts->extents);
+	Free(pexts);
+	Free(fmap);
+
+	return ret;
+}
+
+/*
+ * pmem2_extents_destroy -- free extents structure
+ */
+void
+pmem2_extents_destroy(struct extents **exts)
+{
+	LOG(3, "extents %p", exts);
+
+	ASSERTne(exts, NULL);
+
+	if (*exts) {
+		Free((*exts)->extents);
+		Free(*exts);
+		*exts = NULL;
+	}
+}