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authorMike Marshall <hubcap@omnibond.com>2015-07-17 17:38:12 +0300
committerMike Marshall <hubcap@omnibond.com>2015-10-03 18:39:54 +0300
commit5db11c21a929cd9d8c0484006efb1014fc723c93 (patch)
tree014b77a693c2b33c4558903e325ec0a2e9c0ebf6 /fs/orangefs/dir.c
parentf7ab093f74bf638ed98fd1115f3efa17e308bb7f (diff)
downloadlinux-5db11c21a929cd9d8c0484006efb1014fc723c93.tar.xz
Orangefs: kernel client part 2
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Diffstat (limited to 'fs/orangefs/dir.c')
-rw-r--r--fs/orangefs/dir.c394
1 files changed, 394 insertions, 0 deletions
diff --git a/fs/orangefs/dir.c b/fs/orangefs/dir.c
new file mode 100644
index 000000000000..9b5f4bb17874
--- /dev/null
+++ b/fs/orangefs/dir.c
@@ -0,0 +1,394 @@
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * See COPYING in top-level directory.
+ */
+
+#include "protocol.h"
+#include "pvfs2-kernel.h"
+#include "pvfs2-bufmap.h"
+
+struct readdir_handle_s {
+ int buffer_index;
+ struct pvfs2_readdir_response_s readdir_response;
+ void *dents_buf;
+};
+
+/*
+ * decode routine needed by kmod to make sense of the shared page for readdirs.
+ */
+static long decode_dirents(char *ptr, struct pvfs2_readdir_response_s *readdir)
+{
+ int i;
+ struct pvfs2_readdir_response_s *rd =
+ (struct pvfs2_readdir_response_s *) ptr;
+ char *buf = ptr;
+ char **pptr = &buf;
+
+ readdir->token = rd->token;
+ readdir->pvfs_dirent_outcount = rd->pvfs_dirent_outcount;
+ readdir->dirent_array = kmalloc(readdir->pvfs_dirent_outcount *
+ sizeof(*readdir->dirent_array),
+ GFP_KERNEL);
+ if (readdir->dirent_array == NULL)
+ return -ENOMEM;
+ *pptr += offsetof(struct pvfs2_readdir_response_s, dirent_array);
+ for (i = 0; i < readdir->pvfs_dirent_outcount; i++) {
+ dec_string(pptr, &readdir->dirent_array[i].d_name,
+ &readdir->dirent_array[i].d_length);
+ readdir->dirent_array[i].khandle =
+ *(struct pvfs2_khandle *) *pptr;
+ *pptr += 16;
+ }
+ return (unsigned long)*pptr - (unsigned long)ptr;
+}
+
+static long readdir_handle_ctor(struct readdir_handle_s *rhandle, void *buf,
+ int buffer_index)
+{
+ long ret;
+
+ if (buf == NULL) {
+ gossip_err
+ ("Invalid NULL buffer specified in readdir_handle_ctor\n");
+ return -ENOMEM;
+ }
+ if (buffer_index < 0) {
+ gossip_err
+ ("Invalid buffer index specified in readdir_handle_ctor\n");
+ return -EINVAL;
+ }
+ rhandle->buffer_index = buffer_index;
+ rhandle->dents_buf = buf;
+ ret = decode_dirents(buf, &rhandle->readdir_response);
+ if (ret < 0) {
+ gossip_err("Could not decode readdir from buffer %ld\n", ret);
+ rhandle->buffer_index = -1;
+ gossip_debug(GOSSIP_DIR_DEBUG, "vfree %p\n", buf);
+ vfree(buf);
+ rhandle->dents_buf = NULL;
+ }
+ return ret;
+}
+
+static void readdir_handle_dtor(struct pvfs2_bufmap *bufmap,
+ struct readdir_handle_s *rhandle)
+{
+ if (rhandle == NULL)
+ return;
+
+ /* kfree(NULL) is safe */
+ kfree(rhandle->readdir_response.dirent_array);
+ rhandle->readdir_response.dirent_array = NULL;
+
+ if (rhandle->buffer_index >= 0) {
+ readdir_index_put(bufmap, rhandle->buffer_index);
+ rhandle->buffer_index = -1;
+ }
+ if (rhandle->dents_buf) {
+ gossip_debug(GOSSIP_DIR_DEBUG, "vfree %p\n",
+ rhandle->dents_buf);
+ vfree(rhandle->dents_buf);
+ rhandle->dents_buf = NULL;
+ }
+}
+
+/*
+ * Read directory entries from an instance of an open directory.
+ *
+ * \note This routine was converted for the readdir to iterate change
+ * in "struct file_operations". "converted" mostly amounts to
+ * changing occurrences of "readdir" and "filldir" in the
+ * comments to "iterate" and "dir_emit". Also filldir calls
+ * were changed to dir_emit calls.
+ *
+ * \param dir_emit callback function called for each entry read.
+ *
+ * \retval <0 on error
+ * \retval 0 when directory has been completely traversed
+ * \retval >0 if we don't call dir_emit for all entries
+ *
+ * \note If the dir_emit call-back returns non-zero, then iterate should
+ * assume that it has had enough, and should return as well.
+ */
+static int pvfs2_readdir(struct file *file, struct dir_context *ctx)
+{
+ struct pvfs2_bufmap *bufmap = NULL;
+ int ret = 0;
+ int buffer_index;
+ __u64 *ptoken = file->private_data;
+ __u64 pos = 0;
+ ino_t ino = 0;
+ struct dentry *dentry = file->f_path.dentry;
+ struct pvfs2_kernel_op_s *new_op = NULL;
+ struct pvfs2_inode_s *pvfs2_inode = PVFS2_I(dentry->d_inode);
+ int buffer_full = 0;
+ struct readdir_handle_s rhandle;
+ int i = 0;
+ int len = 0;
+ ino_t current_ino = 0;
+ char *current_entry = NULL;
+ long bytes_decoded;
+
+ gossip_ldebug(GOSSIP_DIR_DEBUG,
+ "%s: ctx->pos:%lld, token = %llu\n",
+ __func__,
+ lld(ctx->pos),
+ llu(*ptoken));
+
+ pos = (__u64) ctx->pos;
+
+ /* are we done? */
+ if (pos == PVFS_READDIR_END) {
+ gossip_debug(GOSSIP_DIR_DEBUG,
+ "Skipping to termination path\n");
+ return 0;
+ }
+
+ gossip_debug(GOSSIP_DIR_DEBUG,
+ "pvfs2_readdir called on %s (pos=%llu)\n",
+ dentry->d_name.name, llu(pos));
+
+ rhandle.buffer_index = -1;
+ rhandle.dents_buf = NULL;
+ memset(&rhandle.readdir_response, 0, sizeof(rhandle.readdir_response));
+
+ new_op = op_alloc(PVFS2_VFS_OP_READDIR);
+ if (!new_op)
+ return -ENOMEM;
+
+ new_op->uses_shared_memory = 1;
+ new_op->upcall.req.readdir.refn = pvfs2_inode->refn;
+ new_op->upcall.req.readdir.max_dirent_count = MAX_DIRENT_COUNT_READDIR;
+
+ gossip_debug(GOSSIP_DIR_DEBUG,
+ "%s: upcall.req.readdir.refn.khandle: %pU\n",
+ __func__,
+ &new_op->upcall.req.readdir.refn.khandle);
+
+ /*
+ * NOTE: the position we send to the readdir upcall is out of
+ * sync with ctx->pos since:
+ * 1. pvfs2 doesn't include the "." and ".." entries that are
+ * added below.
+ * 2. the introduction of distributed directory logic makes token no
+ * longer be related to f_pos and pos. Instead an independent
+ * variable is used inside the function and stored in the
+ * private_data of the file structure.
+ */
+ new_op->upcall.req.readdir.token = *ptoken;
+
+get_new_buffer_index:
+ ret = readdir_index_get(&bufmap, &buffer_index);
+ if (ret < 0) {
+ gossip_lerr("pvfs2_readdir: readdir_index_get() failure (%d)\n",
+ ret);
+ goto out_free_op;
+ }
+ new_op->upcall.req.readdir.buf_index = buffer_index;
+
+ ret = service_operation(new_op,
+ "pvfs2_readdir",
+ get_interruptible_flag(dentry->d_inode));
+
+ gossip_debug(GOSSIP_DIR_DEBUG,
+ "Readdir downcall status is %d. ret:%d\n",
+ new_op->downcall.status,
+ ret);
+
+ if (ret == -EAGAIN && op_state_purged(new_op)) {
+ /*
+ * readdir shared memory aread has been wiped due to
+ * pvfs2-client-core restarting, so we must get a new
+ * index into the shared memory.
+ */
+ gossip_debug(GOSSIP_DIR_DEBUG,
+ "%s: Getting new buffer_index for retry of readdir..\n",
+ __func__);
+ readdir_index_put(bufmap, buffer_index);
+ goto get_new_buffer_index;
+ }
+
+ if (ret == -EIO && op_state_purged(new_op)) {
+ gossip_err("%s: Client is down. Aborting readdir call.\n",
+ __func__);
+ readdir_index_put(bufmap, buffer_index);
+ goto out_free_op;
+ }
+
+ if (ret < 0 || new_op->downcall.status != 0) {
+ gossip_debug(GOSSIP_DIR_DEBUG,
+ "Readdir request failed. Status:%d\n",
+ new_op->downcall.status);
+ readdir_index_put(bufmap, buffer_index);
+ if (ret >= 0)
+ ret = new_op->downcall.status;
+ goto out_free_op;
+ }
+
+ bytes_decoded =
+ readdir_handle_ctor(&rhandle,
+ new_op->downcall.trailer_buf,
+ buffer_index);
+ if (bytes_decoded < 0) {
+ gossip_err("pvfs2_readdir: Could not decode trailer buffer into a readdir response %d\n",
+ ret);
+ ret = bytes_decoded;
+ readdir_index_put(bufmap, buffer_index);
+ goto out_free_op;
+ }
+
+ if (bytes_decoded != new_op->downcall.trailer_size) {
+ gossip_err("pvfs2_readdir: # bytes decoded (%ld) != trailer size (%ld)\n",
+ bytes_decoded,
+ (long)new_op->downcall.trailer_size);
+ ret = -EINVAL;
+ goto out_destroy_handle;
+ }
+
+ if (pos == 0) {
+ ino = get_ino_from_khandle(dentry->d_inode);
+ gossip_debug(GOSSIP_DIR_DEBUG,
+ "%s: calling dir_emit of \".\" with pos = %llu\n",
+ __func__,
+ llu(pos));
+ ret = dir_emit(ctx, ".", 1, ino, DT_DIR);
+ if (ret < 0)
+ goto out_destroy_handle;
+ ctx->pos++;
+ gossip_ldebug(GOSSIP_DIR_DEBUG,
+ "%s: ctx->pos:%lld\n",
+ __func__,
+ lld(ctx->pos));
+ pos++;
+ }
+
+ if (pos == 1) {
+ ino = get_parent_ino_from_dentry(dentry);
+ gossip_debug(GOSSIP_DIR_DEBUG,
+ "%s: calling dir_emit of \"..\" with pos = %llu\n",
+ __func__,
+ llu(pos));
+ ret = dir_emit(ctx, "..", 2, ino, DT_DIR);
+ if (ret < 0)
+ goto out_destroy_handle;
+ ctx->pos++;
+ gossip_ldebug(GOSSIP_DIR_DEBUG,
+ "%s: ctx->pos:%lld\n",
+ __func__,
+ lld(ctx->pos));
+ pos++;
+ }
+
+ for (i = 0; i < rhandle.readdir_response.pvfs_dirent_outcount; i++) {
+ len = rhandle.readdir_response.dirent_array[i].d_length;
+ current_entry = rhandle.readdir_response.dirent_array[i].d_name;
+ current_ino = pvfs2_khandle_to_ino(
+ &(rhandle.readdir_response.dirent_array[i].khandle));
+
+ gossip_debug(GOSSIP_DIR_DEBUG,
+ "calling dir_emit for %s with len %d, pos %ld\n",
+ current_entry,
+ len,
+ (unsigned long)pos);
+ ret =
+ dir_emit(ctx, current_entry, len, current_ino, DT_UNKNOWN);
+ if (ret < 0) {
+ gossip_debug(GOSSIP_DIR_DEBUG,
+ "dir_emit() failed. ret:%d\n",
+ ret);
+ if (i < 2) {
+ gossip_err("dir_emit failed on one of the first two true PVFS directory entries.\n");
+ gossip_err("Duplicate entries may appear.\n");
+ }
+ buffer_full = 1;
+ break;
+ }
+ ctx->pos++;
+ gossip_ldebug(GOSSIP_DIR_DEBUG,
+ "%s: ctx->pos:%lld\n",
+ __func__,
+ lld(ctx->pos));
+
+ pos++;
+ }
+
+ /* this means that all of the dir_emit calls succeeded */
+ if (i == rhandle.readdir_response.pvfs_dirent_outcount) {
+ /* update token */
+ *ptoken = rhandle.readdir_response.token;
+ } else {
+ /* this means a dir_emit call failed */
+ if (rhandle.readdir_response.token == PVFS_READDIR_END) {
+ /*
+ * If PVFS hit end of directory, then there
+ * is no way to do math on the token that it
+ * returned. Instead we go by ctx->pos but
+ * back up to account for the artificial .
+ * and .. entries.
+ */
+ ctx->pos -= 3;
+ } else {
+ /*
+ * this means a dir_emit call failed. !!! need to set
+ * back to previous ctx->pos, no middle value allowed
+ */
+ pos -= (i - 1);
+ ctx->pos -= (i - 1);
+ }
+ gossip_debug(GOSSIP_DIR_DEBUG,
+ "at least one dir_emit call failed. Setting ctx->pos to: %lld\n",
+ lld(ctx->pos));
+ }
+
+ /*
+ * Did we hit the end of the directory?
+ */
+ if (rhandle.readdir_response.token == PVFS_READDIR_END &&
+ !buffer_full) {
+ gossip_debug(GOSSIP_DIR_DEBUG, "End of dir detected; setting ctx->pos to PVFS_READDIR_END.\n");
+ ctx->pos = PVFS_READDIR_END;
+ }
+
+ gossip_debug(GOSSIP_DIR_DEBUG,
+ "pos = %llu, token = %llu"
+ ", ctx->pos should have been %lld\n",
+ llu(pos),
+ llu(*ptoken),
+ lld(ctx->pos));
+
+out_destroy_handle:
+ readdir_handle_dtor(bufmap, &rhandle);
+out_free_op:
+ op_release(new_op);
+ gossip_debug(GOSSIP_DIR_DEBUG, "pvfs2_readdir returning %d\n", ret);
+ return ret;
+}
+
+static int pvfs2_dir_open(struct inode *inode, struct file *file)
+{
+ __u64 *ptoken;
+
+ file->private_data = kmalloc(sizeof(__u64), GFP_KERNEL);
+ if (!file->private_data)
+ return -ENOMEM;
+
+ ptoken = file->private_data;
+ *ptoken = PVFS_READDIR_START;
+ return 0;
+}
+
+static int pvfs2_dir_release(struct inode *inode, struct file *file)
+{
+ pvfs2_flush_inode(inode);
+ kfree(file->private_data);
+ return 0;
+}
+
+/** PVFS2 implementation of VFS directory operations */
+const struct file_operations pvfs2_dir_operations = {
+ .read = generic_read_dir,
+ .iterate = pvfs2_readdir,
+ .open = pvfs2_dir_open,
+ .release = pvfs2_dir_release,
+};