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-rw-r--r--fs/ceph/file.c1344
1 files changed, 1344 insertions, 0 deletions
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
new file mode 100644
index 000000000..3b6b522b4
--- /dev/null
+++ b/fs/ceph/file.c
@@ -0,0 +1,1344 @@
+#include <linux/ceph/ceph_debug.h>
+
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/file.h>
+#include <linux/mount.h>
+#include <linux/namei.h>
+#include <linux/writeback.h>
+#include <linux/falloc.h>
+
+#include "super.h"
+#include "mds_client.h"
+#include "cache.h"
+
+/*
+ * Ceph file operations
+ *
+ * Implement basic open/close functionality, and implement
+ * read/write.
+ *
+ * We implement three modes of file I/O:
+ * - buffered uses the generic_file_aio_{read,write} helpers
+ *
+ * - synchronous is used when there is multi-client read/write
+ * sharing, avoids the page cache, and synchronously waits for an
+ * ack from the OSD.
+ *
+ * - direct io takes the variant of the sync path that references
+ * user pages directly.
+ *
+ * fsync() flushes and waits on dirty pages, but just queues metadata
+ * for writeback: since the MDS can recover size and mtime there is no
+ * need to wait for MDS acknowledgement.
+ */
+
+
+/*
+ * Prepare an open request. Preallocate ceph_cap to avoid an
+ * inopportune ENOMEM later.
+ */
+static struct ceph_mds_request *
+prepare_open_request(struct super_block *sb, int flags, int create_mode)
+{
+ struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
+ struct ceph_mds_client *mdsc = fsc->mdsc;
+ struct ceph_mds_request *req;
+ int want_auth = USE_ANY_MDS;
+ int op = (flags & O_CREAT) ? CEPH_MDS_OP_CREATE : CEPH_MDS_OP_OPEN;
+
+ if (flags & (O_WRONLY|O_RDWR|O_CREAT|O_TRUNC))
+ want_auth = USE_AUTH_MDS;
+
+ req = ceph_mdsc_create_request(mdsc, op, want_auth);
+ if (IS_ERR(req))
+ goto out;
+ req->r_fmode = ceph_flags_to_mode(flags);
+ req->r_args.open.flags = cpu_to_le32(flags);
+ req->r_args.open.mode = cpu_to_le32(create_mode);
+out:
+ return req;
+}
+
+/*
+ * initialize private struct file data.
+ * if we fail, clean up by dropping fmode reference on the ceph_inode
+ */
+static int ceph_init_file(struct inode *inode, struct file *file, int fmode)
+{
+ struct ceph_file_info *cf;
+ int ret = 0;
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
+ struct ceph_mds_client *mdsc = fsc->mdsc;
+
+ switch (inode->i_mode & S_IFMT) {
+ case S_IFREG:
+ /* First file open request creates the cookie, we want to keep
+ * this cookie around for the filetime of the inode as not to
+ * have to worry about fscache register / revoke / operation
+ * races.
+ *
+ * Also, if we know the operation is going to invalidate data
+ * (non readonly) just nuke the cache right away.
+ */
+ ceph_fscache_register_inode_cookie(mdsc->fsc, ci);
+ if ((fmode & CEPH_FILE_MODE_WR))
+ ceph_fscache_invalidate(inode);
+ case S_IFDIR:
+ dout("init_file %p %p 0%o (regular)\n", inode, file,
+ inode->i_mode);
+ cf = kmem_cache_alloc(ceph_file_cachep, GFP_NOFS | __GFP_ZERO);
+ if (cf == NULL) {
+ ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
+ return -ENOMEM;
+ }
+ cf->fmode = fmode;
+ cf->next_offset = 2;
+ file->private_data = cf;
+ BUG_ON(inode->i_fop->release != ceph_release);
+ break;
+
+ case S_IFLNK:
+ dout("init_file %p %p 0%o (symlink)\n", inode, file,
+ inode->i_mode);
+ ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
+ break;
+
+ default:
+ dout("init_file %p %p 0%o (special)\n", inode, file,
+ inode->i_mode);
+ /*
+ * we need to drop the open ref now, since we don't
+ * have .release set to ceph_release.
+ */
+ ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
+ BUG_ON(inode->i_fop->release == ceph_release);
+
+ /* call the proper open fop */
+ ret = inode->i_fop->open(inode, file);
+ }
+ return ret;
+}
+
+/*
+ * If we already have the requisite capabilities, we can satisfy
+ * the open request locally (no need to request new caps from the
+ * MDS). We do, however, need to inform the MDS (asynchronously)
+ * if our wanted caps set expands.
+ */
+int ceph_open(struct inode *inode, struct file *file)
+{
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
+ struct ceph_mds_client *mdsc = fsc->mdsc;
+ struct ceph_mds_request *req;
+ struct ceph_file_info *cf = file->private_data;
+ struct inode *parent_inode = NULL;
+ int err;
+ int flags, fmode, wanted;
+
+ if (cf) {
+ dout("open file %p is already opened\n", file);
+ return 0;
+ }
+
+ /* filter out O_CREAT|O_EXCL; vfs did that already. yuck. */
+ flags = file->f_flags & ~(O_CREAT|O_EXCL);
+ if (S_ISDIR(inode->i_mode))
+ flags = O_DIRECTORY; /* mds likes to know */
+
+ dout("open inode %p ino %llx.%llx file %p flags %d (%d)\n", inode,
+ ceph_vinop(inode), file, flags, file->f_flags);
+ fmode = ceph_flags_to_mode(flags);
+ wanted = ceph_caps_for_mode(fmode);
+
+ /* snapped files are read-only */
+ if (ceph_snap(inode) != CEPH_NOSNAP && (file->f_mode & FMODE_WRITE))
+ return -EROFS;
+
+ /* trivially open snapdir */
+ if (ceph_snap(inode) == CEPH_SNAPDIR) {
+ spin_lock(&ci->i_ceph_lock);
+ __ceph_get_fmode(ci, fmode);
+ spin_unlock(&ci->i_ceph_lock);
+ return ceph_init_file(inode, file, fmode);
+ }
+
+ /*
+ * No need to block if we have caps on the auth MDS (for
+ * write) or any MDS (for read). Update wanted set
+ * asynchronously.
+ */
+ spin_lock(&ci->i_ceph_lock);
+ if (__ceph_is_any_real_caps(ci) &&
+ (((fmode & CEPH_FILE_MODE_WR) == 0) || ci->i_auth_cap)) {
+ int mds_wanted = __ceph_caps_mds_wanted(ci);
+ int issued = __ceph_caps_issued(ci, NULL);
+
+ dout("open %p fmode %d want %s issued %s using existing\n",
+ inode, fmode, ceph_cap_string(wanted),
+ ceph_cap_string(issued));
+ __ceph_get_fmode(ci, fmode);
+ spin_unlock(&ci->i_ceph_lock);
+
+ /* adjust wanted? */
+ if ((issued & wanted) != wanted &&
+ (mds_wanted & wanted) != wanted &&
+ ceph_snap(inode) != CEPH_SNAPDIR)
+ ceph_check_caps(ci, 0, NULL);
+
+ return ceph_init_file(inode, file, fmode);
+ } else if (ceph_snap(inode) != CEPH_NOSNAP &&
+ (ci->i_snap_caps & wanted) == wanted) {
+ __ceph_get_fmode(ci, fmode);
+ spin_unlock(&ci->i_ceph_lock);
+ return ceph_init_file(inode, file, fmode);
+ }
+
+ spin_unlock(&ci->i_ceph_lock);
+
+ dout("open fmode %d wants %s\n", fmode, ceph_cap_string(wanted));
+ req = prepare_open_request(inode->i_sb, flags, 0);
+ if (IS_ERR(req)) {
+ err = PTR_ERR(req);
+ goto out;
+ }
+ req->r_inode = inode;
+ ihold(inode);
+
+ req->r_num_caps = 1;
+ if (flags & O_CREAT)
+ parent_inode = ceph_get_dentry_parent_inode(file->f_path.dentry);
+ err = ceph_mdsc_do_request(mdsc, parent_inode, req);
+ iput(parent_inode);
+ if (!err)
+ err = ceph_init_file(inode, file, req->r_fmode);
+ ceph_mdsc_put_request(req);
+ dout("open result=%d on %llx.%llx\n", err, ceph_vinop(inode));
+out:
+ return err;
+}
+
+
+/*
+ * Do a lookup + open with a single request. If we get a non-existent
+ * file or symlink, return 1 so the VFS can retry.
+ */
+int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
+ struct file *file, unsigned flags, umode_t mode,
+ int *opened)
+{
+ struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
+ struct ceph_mds_client *mdsc = fsc->mdsc;
+ struct ceph_mds_request *req;
+ struct dentry *dn;
+ struct ceph_acls_info acls = {};
+ int err;
+
+ dout("atomic_open %p dentry %p '%pd' %s flags %d mode 0%o\n",
+ dir, dentry, dentry,
+ d_unhashed(dentry) ? "unhashed" : "hashed", flags, mode);
+
+ if (dentry->d_name.len > NAME_MAX)
+ return -ENAMETOOLONG;
+
+ err = ceph_init_dentry(dentry);
+ if (err < 0)
+ return err;
+
+ if (flags & O_CREAT) {
+ err = ceph_pre_init_acls(dir, &mode, &acls);
+ if (err < 0)
+ return err;
+ }
+
+ /* do the open */
+ req = prepare_open_request(dir->i_sb, flags, mode);
+ if (IS_ERR(req)) {
+ err = PTR_ERR(req);
+ goto out_acl;
+ }
+ req->r_dentry = dget(dentry);
+ req->r_num_caps = 2;
+ if (flags & O_CREAT) {
+ req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
+ req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
+ if (acls.pagelist) {
+ req->r_pagelist = acls.pagelist;
+ acls.pagelist = NULL;
+ }
+ }
+ req->r_locked_dir = dir; /* caller holds dir->i_mutex */
+ err = ceph_mdsc_do_request(mdsc,
+ (flags & (O_CREAT|O_TRUNC)) ? dir : NULL,
+ req);
+ err = ceph_handle_snapdir(req, dentry, err);
+ if (err)
+ goto out_req;
+
+ if (err == 0 && (flags & O_CREAT) && !req->r_reply_info.head->is_dentry)
+ err = ceph_handle_notrace_create(dir, dentry);
+
+ if (d_unhashed(dentry)) {
+ dn = ceph_finish_lookup(req, dentry, err);
+ if (IS_ERR(dn))
+ err = PTR_ERR(dn);
+ } else {
+ /* we were given a hashed negative dentry */
+ dn = NULL;
+ }
+ if (err)
+ goto out_req;
+ if (dn || d_really_is_negative(dentry) || d_is_symlink(dentry)) {
+ /* make vfs retry on splice, ENOENT, or symlink */
+ dout("atomic_open finish_no_open on dn %p\n", dn);
+ err = finish_no_open(file, dn);
+ } else {
+ dout("atomic_open finish_open on dn %p\n", dn);
+ if (req->r_op == CEPH_MDS_OP_CREATE && req->r_reply_info.has_create_ino) {
+ ceph_init_inode_acls(d_inode(dentry), &acls);
+ *opened |= FILE_CREATED;
+ }
+ err = finish_open(file, dentry, ceph_open, opened);
+ }
+out_req:
+ if (!req->r_err && req->r_target_inode)
+ ceph_put_fmode(ceph_inode(req->r_target_inode), req->r_fmode);
+ ceph_mdsc_put_request(req);
+out_acl:
+ ceph_release_acls_info(&acls);
+ dout("atomic_open result=%d\n", err);
+ return err;
+}
+
+int ceph_release(struct inode *inode, struct file *file)
+{
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ struct ceph_file_info *cf = file->private_data;
+
+ dout("release inode %p file %p\n", inode, file);
+ ceph_put_fmode(ci, cf->fmode);
+ if (cf->last_readdir)
+ ceph_mdsc_put_request(cf->last_readdir);
+ kfree(cf->last_name);
+ kfree(cf->dir_info);
+ dput(cf->dentry);
+ kmem_cache_free(ceph_file_cachep, cf);
+
+ /* wake up anyone waiting for caps on this inode */
+ wake_up_all(&ci->i_cap_wq);
+ return 0;
+}
+
+enum {
+ CHECK_EOF = 1,
+ READ_INLINE = 2,
+};
+
+/*
+ * Read a range of bytes striped over one or more objects. Iterate over
+ * objects we stripe over. (That's not atomic, but good enough for now.)
+ *
+ * If we get a short result from the OSD, check against i_size; we need to
+ * only return a short read to the caller if we hit EOF.
+ */
+static int striped_read(struct inode *inode,
+ u64 off, u64 len,
+ struct page **pages, int num_pages,
+ int *checkeof, bool o_direct,
+ unsigned long buf_align)
+{
+ struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ u64 pos, this_len, left;
+ int io_align, page_align;
+ int pages_left;
+ int read;
+ struct page **page_pos;
+ int ret;
+ bool hit_stripe, was_short;
+
+ /*
+ * we may need to do multiple reads. not atomic, unfortunately.
+ */
+ pos = off;
+ left = len;
+ page_pos = pages;
+ pages_left = num_pages;
+ read = 0;
+ io_align = off & ~PAGE_MASK;
+
+more:
+ if (o_direct)
+ page_align = (pos - io_align + buf_align) & ~PAGE_MASK;
+ else
+ page_align = pos & ~PAGE_MASK;
+ this_len = left;
+ ret = ceph_osdc_readpages(&fsc->client->osdc, ceph_vino(inode),
+ &ci->i_layout, pos, &this_len,
+ ci->i_truncate_seq,
+ ci->i_truncate_size,
+ page_pos, pages_left, page_align);
+ if (ret == -ENOENT)
+ ret = 0;
+ hit_stripe = this_len < left;
+ was_short = ret >= 0 && ret < this_len;
+ dout("striped_read %llu~%llu (read %u) got %d%s%s\n", pos, left, read,
+ ret, hit_stripe ? " HITSTRIPE" : "", was_short ? " SHORT" : "");
+
+ if (ret >= 0) {
+ int didpages;
+ if (was_short && (pos + ret < inode->i_size)) {
+ int zlen = min(this_len - ret,
+ inode->i_size - pos - ret);
+ int zoff = (o_direct ? buf_align : io_align) +
+ read + ret;
+ dout(" zero gap %llu to %llu\n",
+ pos + ret, pos + ret + zlen);
+ ceph_zero_page_vector_range(zoff, zlen, pages);
+ ret += zlen;
+ }
+
+ didpages = (page_align + ret) >> PAGE_CACHE_SHIFT;
+ pos += ret;
+ read = pos - off;
+ left -= ret;
+ page_pos += didpages;
+ pages_left -= didpages;
+
+ /* hit stripe and need continue*/
+ if (left && hit_stripe && pos < inode->i_size)
+ goto more;
+ }
+
+ if (read > 0) {
+ ret = read;
+ /* did we bounce off eof? */
+ if (pos + left > inode->i_size)
+ *checkeof = CHECK_EOF;
+ }
+
+ dout("striped_read returns %d\n", ret);
+ return ret;
+}
+
+/*
+ * Completely synchronous read and write methods. Direct from __user
+ * buffer to osd, or directly to user pages (if O_DIRECT).
+ *
+ * If the read spans object boundary, just do multiple reads.
+ */
+static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *i,
+ int *checkeof)
+{
+ struct file *file = iocb->ki_filp;
+ struct inode *inode = file_inode(file);
+ struct page **pages;
+ u64 off = iocb->ki_pos;
+ int num_pages, ret;
+ size_t len = iov_iter_count(i);
+
+ dout("sync_read on file %p %llu~%u %s\n", file, off,
+ (unsigned)len,
+ (file->f_flags & O_DIRECT) ? "O_DIRECT" : "");
+
+ if (!len)
+ return 0;
+ /*
+ * flush any page cache pages in this range. this
+ * will make concurrent normal and sync io slow,
+ * but it will at least behave sensibly when they are
+ * in sequence.
+ */
+ ret = filemap_write_and_wait_range(inode->i_mapping, off,
+ off + len);
+ if (ret < 0)
+ return ret;
+
+ if (iocb->ki_flags & IOCB_DIRECT) {
+ while (iov_iter_count(i)) {
+ size_t start;
+ ssize_t n;
+
+ n = iov_iter_get_pages_alloc(i, &pages, INT_MAX, &start);
+ if (n < 0)
+ return n;
+
+ num_pages = (n + start + PAGE_SIZE - 1) / PAGE_SIZE;
+
+ ret = striped_read(inode, off, n,
+ pages, num_pages, checkeof,
+ 1, start);
+
+ ceph_put_page_vector(pages, num_pages, true);
+
+ if (ret <= 0)
+ break;
+ off += ret;
+ iov_iter_advance(i, ret);
+ if (ret < n)
+ break;
+ }
+ } else {
+ num_pages = calc_pages_for(off, len);
+ pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);
+ if (IS_ERR(pages))
+ return PTR_ERR(pages);
+ ret = striped_read(inode, off, len, pages,
+ num_pages, checkeof, 0, 0);
+ if (ret > 0) {
+ int l, k = 0;
+ size_t left = ret;
+
+ while (left) {
+ size_t page_off = off & ~PAGE_MASK;
+ size_t copy = min_t(size_t,
+ PAGE_SIZE - page_off, left);
+ l = copy_page_to_iter(pages[k++], page_off,
+ copy, i);
+ off += l;
+ left -= l;
+ if (l < copy)
+ break;
+ }
+ }
+ ceph_release_page_vector(pages, num_pages);
+ }
+
+ if (off > iocb->ki_pos) {
+ ret = off - iocb->ki_pos;
+ iocb->ki_pos = off;
+ }
+
+ dout("sync_read result %d\n", ret);
+ return ret;
+}
+
+/*
+ * Write commit request unsafe callback, called to tell us when a
+ * request is unsafe (that is, in flight--has been handed to the
+ * messenger to send to its target osd). It is called again when
+ * we've received a response message indicating the request is
+ * "safe" (its CEPH_OSD_FLAG_ONDISK flag is set), or when a request
+ * is completed early (and unsuccessfully) due to a timeout or
+ * interrupt.
+ *
+ * This is used if we requested both an ACK and ONDISK commit reply
+ * from the OSD.
+ */
+static void ceph_sync_write_unsafe(struct ceph_osd_request *req, bool unsafe)
+{
+ struct ceph_inode_info *ci = ceph_inode(req->r_inode);
+
+ dout("%s %p tid %llu %ssafe\n", __func__, req, req->r_tid,
+ unsafe ? "un" : "");
+ if (unsafe) {
+ ceph_get_cap_refs(ci, CEPH_CAP_FILE_WR);
+ spin_lock(&ci->i_unsafe_lock);
+ list_add_tail(&req->r_unsafe_item,
+ &ci->i_unsafe_writes);
+ spin_unlock(&ci->i_unsafe_lock);
+ } else {
+ spin_lock(&ci->i_unsafe_lock);
+ list_del_init(&req->r_unsafe_item);
+ spin_unlock(&ci->i_unsafe_lock);
+ ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR);
+ }
+}
+
+
+/*
+ * Synchronous write, straight from __user pointer or user pages.
+ *
+ * If write spans object boundary, just do multiple writes. (For a
+ * correct atomic write, we should e.g. take write locks on all
+ * objects, rollback on failure, etc.)
+ */
+static ssize_t
+ceph_sync_direct_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos)
+{
+ struct file *file = iocb->ki_filp;
+ struct inode *inode = file_inode(file);
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
+ struct ceph_snap_context *snapc;
+ struct ceph_vino vino;
+ struct ceph_osd_request *req;
+ struct page **pages;
+ int num_pages;
+ int written = 0;
+ int flags;
+ int check_caps = 0;
+ int ret;
+ struct timespec mtime = CURRENT_TIME;
+ size_t count = iov_iter_count(from);
+
+ if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
+ return -EROFS;
+
+ dout("sync_direct_write on file %p %lld~%u\n", file, pos,
+ (unsigned)count);
+
+ ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
+ if (ret < 0)
+ return ret;
+
+ ret = invalidate_inode_pages2_range(inode->i_mapping,
+ pos >> PAGE_CACHE_SHIFT,
+ (pos + count) >> PAGE_CACHE_SHIFT);
+ if (ret < 0)
+ dout("invalidate_inode_pages2_range returned %d\n", ret);
+
+ flags = CEPH_OSD_FLAG_ORDERSNAP |
+ CEPH_OSD_FLAG_ONDISK |
+ CEPH_OSD_FLAG_WRITE;
+
+ while (iov_iter_count(from) > 0) {
+ u64 len = iov_iter_single_seg_count(from);
+ size_t start;
+ ssize_t n;
+
+ snapc = ci->i_snap_realm->cached_context;
+ vino = ceph_vino(inode);
+ req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
+ vino, pos, &len, 0,
+ 2,/*include a 'startsync' command*/
+ CEPH_OSD_OP_WRITE, flags, snapc,
+ ci->i_truncate_seq,
+ ci->i_truncate_size,
+ false);
+ if (IS_ERR(req)) {
+ ret = PTR_ERR(req);
+ break;
+ }
+
+ osd_req_op_init(req, 1, CEPH_OSD_OP_STARTSYNC);
+
+ n = iov_iter_get_pages_alloc(from, &pages, len, &start);
+ if (unlikely(n < 0)) {
+ ret = n;
+ ceph_osdc_put_request(req);
+ break;
+ }
+
+ num_pages = (n + start + PAGE_SIZE - 1) / PAGE_SIZE;
+ /*
+ * throw out any page cache pages in this range. this
+ * may block.
+ */
+ truncate_inode_pages_range(inode->i_mapping, pos,
+ (pos+n) | (PAGE_CACHE_SIZE-1));
+ osd_req_op_extent_osd_data_pages(req, 0, pages, n, start,
+ false, false);
+
+ /* BUG_ON(vino.snap != CEPH_NOSNAP); */
+ ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
+
+ ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
+ if (!ret)
+ ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
+
+ ceph_put_page_vector(pages, num_pages, false);
+
+ ceph_osdc_put_request(req);
+ if (ret)
+ break;
+ pos += n;
+ written += n;
+ iov_iter_advance(from, n);
+
+ if (pos > i_size_read(inode)) {
+ check_caps = ceph_inode_set_size(inode, pos);
+ if (check_caps)
+ ceph_check_caps(ceph_inode(inode),
+ CHECK_CAPS_AUTHONLY,
+ NULL);
+ }
+ }
+
+ if (ret != -EOLDSNAPC && written > 0) {
+ iocb->ki_pos = pos;
+ ret = written;
+ }
+ return ret;
+}
+
+
+/*
+ * Synchronous write, straight from __user pointer or user pages.
+ *
+ * If write spans object boundary, just do multiple writes. (For a
+ * correct atomic write, we should e.g. take write locks on all
+ * objects, rollback on failure, etc.)
+ */
+static ssize_t
+ceph_sync_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos)
+{
+ struct file *file = iocb->ki_filp;
+ struct inode *inode = file_inode(file);
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
+ struct ceph_snap_context *snapc;
+ struct ceph_vino vino;
+ struct ceph_osd_request *req;
+ struct page **pages;
+ u64 len;
+ int num_pages;
+ int written = 0;
+ int flags;
+ int check_caps = 0;
+ int ret;
+ struct timespec mtime = CURRENT_TIME;
+ size_t count = iov_iter_count(from);
+
+ if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
+ return -EROFS;
+
+ dout("sync_write on file %p %lld~%u\n", file, pos, (unsigned)count);
+
+ ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
+ if (ret < 0)
+ return ret;
+
+ ret = invalidate_inode_pages2_range(inode->i_mapping,
+ pos >> PAGE_CACHE_SHIFT,
+ (pos + count) >> PAGE_CACHE_SHIFT);
+ if (ret < 0)
+ dout("invalidate_inode_pages2_range returned %d\n", ret);
+
+ flags = CEPH_OSD_FLAG_ORDERSNAP |
+ CEPH_OSD_FLAG_ONDISK |
+ CEPH_OSD_FLAG_WRITE |
+ CEPH_OSD_FLAG_ACK;
+
+ while ((len = iov_iter_count(from)) > 0) {
+ size_t left;
+ int n;
+
+ snapc = ci->i_snap_realm->cached_context;
+ vino = ceph_vino(inode);
+ req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
+ vino, pos, &len, 0, 1,
+ CEPH_OSD_OP_WRITE, flags, snapc,
+ ci->i_truncate_seq,
+ ci->i_truncate_size,
+ false);
+ if (IS_ERR(req)) {
+ ret = PTR_ERR(req);
+ break;
+ }
+
+ /*
+ * write from beginning of first page,
+ * regardless of io alignment
+ */
+ num_pages = (len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+
+ pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);
+ if (IS_ERR(pages)) {
+ ret = PTR_ERR(pages);
+ goto out;
+ }
+
+ left = len;
+ for (n = 0; n < num_pages; n++) {
+ size_t plen = min_t(size_t, left, PAGE_SIZE);
+ ret = copy_page_from_iter(pages[n], 0, plen, from);
+ if (ret != plen) {
+ ret = -EFAULT;
+ break;
+ }
+ left -= ret;
+ }
+
+ if (ret < 0) {
+ ceph_release_page_vector(pages, num_pages);
+ goto out;
+ }
+
+ /* get a second commit callback */
+ req->r_unsafe_callback = ceph_sync_write_unsafe;
+ req->r_inode = inode;
+
+ osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0,
+ false, true);
+
+ /* BUG_ON(vino.snap != CEPH_NOSNAP); */
+ ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
+
+ ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
+ if (!ret)
+ ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
+
+out:
+ ceph_osdc_put_request(req);
+ if (ret == 0) {
+ pos += len;
+ written += len;
+
+ if (pos > i_size_read(inode)) {
+ check_caps = ceph_inode_set_size(inode, pos);
+ if (check_caps)
+ ceph_check_caps(ceph_inode(inode),
+ CHECK_CAPS_AUTHONLY,
+ NULL);
+ }
+ } else
+ break;
+ }
+
+ if (ret != -EOLDSNAPC && written > 0) {
+ ret = written;
+ iocb->ki_pos = pos;
+ }
+ return ret;
+}
+
+/*
+ * Wrap generic_file_aio_read with checks for cap bits on the inode.
+ * Atomically grab references, so that those bits are not released
+ * back to the MDS mid-read.
+ *
+ * Hmm, the sync read case isn't actually async... should it be?
+ */
+static ssize_t ceph_read_iter(struct kiocb *iocb, struct iov_iter *to)
+{
+ struct file *filp = iocb->ki_filp;
+ struct ceph_file_info *fi = filp->private_data;
+ size_t len = iov_iter_count(to);
+ struct inode *inode = file_inode(filp);
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ struct page *pinned_page = NULL;
+ ssize_t ret;
+ int want, got = 0;
+ int retry_op = 0, read = 0;
+
+again:
+ dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n",
+ inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len, inode);
+
+ if (fi->fmode & CEPH_FILE_MODE_LAZY)
+ want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
+ else
+ want = CEPH_CAP_FILE_CACHE;
+ ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, -1, &got, &pinned_page);
+ if (ret < 0)
+ return ret;
+
+ if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 ||
+ (iocb->ki_flags & IOCB_DIRECT) ||
+ (fi->flags & CEPH_F_SYNC)) {
+
+ dout("aio_sync_read %p %llx.%llx %llu~%u got cap refs on %s\n",
+ inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
+ ceph_cap_string(got));
+
+ if (ci->i_inline_version == CEPH_INLINE_NONE) {
+ /* hmm, this isn't really async... */
+ ret = ceph_sync_read(iocb, to, &retry_op);
+ } else {
+ retry_op = READ_INLINE;
+ }
+ } else {
+ dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n",
+ inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
+ ceph_cap_string(got));
+
+ ret = generic_file_read_iter(iocb, to);
+ }
+ dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n",
+ inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret);
+ if (pinned_page) {
+ page_cache_release(pinned_page);
+ pinned_page = NULL;
+ }
+ ceph_put_cap_refs(ci, got);
+ if (retry_op && ret >= 0) {
+ int statret;
+ struct page *page = NULL;
+ loff_t i_size;
+ if (retry_op == READ_INLINE) {
+ page = __page_cache_alloc(GFP_NOFS);
+ if (!page)
+ return -ENOMEM;
+ }
+
+ statret = __ceph_do_getattr(inode, page,
+ CEPH_STAT_CAP_INLINE_DATA, !!page);
+ if (statret < 0) {
+ __free_page(page);
+ if (statret == -ENODATA) {
+ BUG_ON(retry_op != READ_INLINE);
+ goto again;
+ }
+ return statret;
+ }
+
+ i_size = i_size_read(inode);
+ if (retry_op == READ_INLINE) {
+ BUG_ON(ret > 0 || read > 0);
+ if (iocb->ki_pos < i_size &&
+ iocb->ki_pos < PAGE_CACHE_SIZE) {
+ loff_t end = min_t(loff_t, i_size,
+ iocb->ki_pos + len);
+ end = min_t(loff_t, end, PAGE_CACHE_SIZE);
+ if (statret < end)
+ zero_user_segment(page, statret, end);
+ ret = copy_page_to_iter(page,
+ iocb->ki_pos & ~PAGE_MASK,
+ end - iocb->ki_pos, to);
+ iocb->ki_pos += ret;
+ read += ret;
+ }
+ if (iocb->ki_pos < i_size && read < len) {
+ size_t zlen = min_t(size_t, len - read,
+ i_size - iocb->ki_pos);
+ ret = iov_iter_zero(zlen, to);
+ iocb->ki_pos += ret;
+ read += ret;
+ }
+ __free_pages(page, 0);
+ return read;
+ }
+
+ /* hit EOF or hole? */
+ if (retry_op == CHECK_EOF && iocb->ki_pos < i_size &&
+ ret < len) {
+ dout("sync_read hit hole, ppos %lld < size %lld"
+ ", reading more\n", iocb->ki_pos,
+ inode->i_size);
+
+ read += ret;
+ len -= ret;
+ retry_op = 0;
+ goto again;
+ }
+ }
+
+ if (ret >= 0)
+ ret += read;
+
+ return ret;
+}
+
+/*
+ * Take cap references to avoid releasing caps to MDS mid-write.
+ *
+ * If we are synchronous, and write with an old snap context, the OSD
+ * may return EOLDSNAPC. In that case, retry the write.. _after_
+ * dropping our cap refs and allowing the pending snap to logically
+ * complete _before_ this write occurs.
+ *
+ * If we are near ENOSPC, write synchronously.
+ */
+static ssize_t ceph_write_iter(struct kiocb *iocb, struct iov_iter *from)
+{
+ struct file *file = iocb->ki_filp;
+ struct ceph_file_info *fi = file->private_data;
+ struct inode *inode = file_inode(file);
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ struct ceph_osd_client *osdc =
+ &ceph_sb_to_client(inode->i_sb)->client->osdc;
+ ssize_t count, written = 0;
+ int err, want, got;
+ loff_t pos;
+
+ if (ceph_snap(inode) != CEPH_NOSNAP)
+ return -EROFS;
+
+ mutex_lock(&inode->i_mutex);
+
+ /* We can write back this queue in page reclaim */
+ current->backing_dev_info = inode_to_bdi(inode);
+
+ err = generic_write_checks(iocb, from);
+ if (err <= 0)
+ goto out;
+
+ pos = iocb->ki_pos;
+ count = iov_iter_count(from);
+ err = file_remove_suid(file);
+ if (err)
+ goto out;
+
+ err = file_update_time(file);
+ if (err)
+ goto out;
+
+ if (ci->i_inline_version != CEPH_INLINE_NONE) {
+ err = ceph_uninline_data(file, NULL);
+ if (err < 0)
+ goto out;
+ }
+
+retry_snap:
+ if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL)) {
+ err = -ENOSPC;
+ goto out;
+ }
+
+ dout("aio_write %p %llx.%llx %llu~%zd getting caps. i_size %llu\n",
+ inode, ceph_vinop(inode), pos, count, inode->i_size);
+ if (fi->fmode & CEPH_FILE_MODE_LAZY)
+ want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
+ else
+ want = CEPH_CAP_FILE_BUFFER;
+ got = 0;
+ err = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, pos + count,
+ &got, NULL);
+ if (err < 0)
+ goto out;
+
+ dout("aio_write %p %llx.%llx %llu~%zd got cap refs on %s\n",
+ inode, ceph_vinop(inode), pos, count, ceph_cap_string(got));
+
+ if ((got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO)) == 0 ||
+ (iocb->ki_flags & IOCB_DIRECT) || (fi->flags & CEPH_F_SYNC)) {
+ struct iov_iter data;
+ mutex_unlock(&inode->i_mutex);
+ /* we might need to revert back to that point */
+ data = *from;
+ if (iocb->ki_flags & IOCB_DIRECT)
+ written = ceph_sync_direct_write(iocb, &data, pos);
+ else
+ written = ceph_sync_write(iocb, &data, pos);
+ if (written == -EOLDSNAPC) {
+ dout("aio_write %p %llx.%llx %llu~%u"
+ "got EOLDSNAPC, retrying\n",
+ inode, ceph_vinop(inode),
+ pos, (unsigned)count);
+ mutex_lock(&inode->i_mutex);
+ goto retry_snap;
+ }
+ if (written > 0)
+ iov_iter_advance(from, written);
+ } else {
+ loff_t old_size = inode->i_size;
+ /*
+ * No need to acquire the i_truncate_mutex. Because
+ * the MDS revokes Fwb caps before sending truncate
+ * message to us. We can't get Fwb cap while there
+ * are pending vmtruncate. So write and vmtruncate
+ * can not run at the same time
+ */
+ written = generic_perform_write(file, from, pos);
+ if (likely(written >= 0))
+ iocb->ki_pos = pos + written;
+ if (inode->i_size > old_size)
+ ceph_fscache_update_objectsize(inode);
+ mutex_unlock(&inode->i_mutex);
+ }
+
+ if (written >= 0) {
+ int dirty;
+ spin_lock(&ci->i_ceph_lock);
+ ci->i_inline_version = CEPH_INLINE_NONE;
+ dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
+ spin_unlock(&ci->i_ceph_lock);
+ if (dirty)
+ __mark_inode_dirty(inode, dirty);
+ }
+
+ dout("aio_write %p %llx.%llx %llu~%u dropping cap refs on %s\n",
+ inode, ceph_vinop(inode), pos, (unsigned)count,
+ ceph_cap_string(got));
+ ceph_put_cap_refs(ci, got);
+
+ if (written >= 0 &&
+ ((file->f_flags & O_SYNC) || IS_SYNC(file->f_mapping->host) ||
+ ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_NEARFULL))) {
+ err = vfs_fsync_range(file, pos, pos + written - 1, 1);
+ if (err < 0)
+ written = err;
+ }
+
+ goto out_unlocked;
+
+out:
+ mutex_unlock(&inode->i_mutex);
+out_unlocked:
+ current->backing_dev_info = NULL;
+ return written ? written : err;
+}
+
+/*
+ * llseek. be sure to verify file size on SEEK_END.
+ */
+static loff_t ceph_llseek(struct file *file, loff_t offset, int whence)
+{
+ struct inode *inode = file->f_mapping->host;
+ int ret;
+
+ mutex_lock(&inode->i_mutex);
+
+ if (whence == SEEK_END || whence == SEEK_DATA || whence == SEEK_HOLE) {
+ ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE, false);
+ if (ret < 0) {
+ offset = ret;
+ goto out;
+ }
+ }
+
+ switch (whence) {
+ case SEEK_END:
+ offset += inode->i_size;
+ break;
+ case SEEK_CUR:
+ /*
+ * Here we special-case the lseek(fd, 0, SEEK_CUR)
+ * position-querying operation. Avoid rewriting the "same"
+ * f_pos value back to the file because a concurrent read(),
+ * write() or lseek() might have altered it
+ */
+ if (offset == 0) {
+ offset = file->f_pos;
+ goto out;
+ }
+ offset += file->f_pos;
+ break;
+ case SEEK_DATA:
+ if (offset >= inode->i_size) {
+ ret = -ENXIO;
+ goto out;
+ }
+ break;
+ case SEEK_HOLE:
+ if (offset >= inode->i_size) {
+ ret = -ENXIO;
+ goto out;
+ }
+ offset = inode->i_size;
+ break;
+ }
+
+ offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
+
+out:
+ mutex_unlock(&inode->i_mutex);
+ return offset;
+}
+
+static inline void ceph_zero_partial_page(
+ struct inode *inode, loff_t offset, unsigned size)
+{
+ struct page *page;
+ pgoff_t index = offset >> PAGE_CACHE_SHIFT;
+
+ page = find_lock_page(inode->i_mapping, index);
+ if (page) {
+ wait_on_page_writeback(page);
+ zero_user(page, offset & (PAGE_CACHE_SIZE - 1), size);
+ unlock_page(page);
+ page_cache_release(page);
+ }
+}
+
+static void ceph_zero_pagecache_range(struct inode *inode, loff_t offset,
+ loff_t length)
+{
+ loff_t nearly = round_up(offset, PAGE_CACHE_SIZE);
+ if (offset < nearly) {
+ loff_t size = nearly - offset;
+ if (length < size)
+ size = length;
+ ceph_zero_partial_page(inode, offset, size);
+ offset += size;
+ length -= size;
+ }
+ if (length >= PAGE_CACHE_SIZE) {
+ loff_t size = round_down(length, PAGE_CACHE_SIZE);
+ truncate_pagecache_range(inode, offset, offset + size - 1);
+ offset += size;
+ length -= size;
+ }
+ if (length)
+ ceph_zero_partial_page(inode, offset, length);
+}
+
+static int ceph_zero_partial_object(struct inode *inode,
+ loff_t offset, loff_t *length)
+{
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
+ struct ceph_osd_request *req;
+ int ret = 0;
+ loff_t zero = 0;
+ int op;
+
+ if (!length) {
+ op = offset ? CEPH_OSD_OP_DELETE : CEPH_OSD_OP_TRUNCATE;
+ length = &zero;
+ } else {
+ op = CEPH_OSD_OP_ZERO;
+ }
+
+ req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
+ ceph_vino(inode),
+ offset, length,
+ 0, 1, op,
+ CEPH_OSD_FLAG_WRITE |
+ CEPH_OSD_FLAG_ONDISK,
+ NULL, 0, 0, false);
+ if (IS_ERR(req)) {
+ ret = PTR_ERR(req);
+ goto out;
+ }
+
+ ceph_osdc_build_request(req, offset, NULL, ceph_vino(inode).snap,
+ &inode->i_mtime);
+
+ ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
+ if (!ret) {
+ ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
+ if (ret == -ENOENT)
+ ret = 0;
+ }
+ ceph_osdc_put_request(req);
+
+out:
+ return ret;
+}
+
+static int ceph_zero_objects(struct inode *inode, loff_t offset, loff_t length)
+{
+ int ret = 0;
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ s32 stripe_unit = ceph_file_layout_su(ci->i_layout);
+ s32 stripe_count = ceph_file_layout_stripe_count(ci->i_layout);
+ s32 object_size = ceph_file_layout_object_size(ci->i_layout);
+ u64 object_set_size = object_size * stripe_count;
+ u64 nearly, t;
+
+ /* round offset up to next period boundary */
+ nearly = offset + object_set_size - 1;
+ t = nearly;
+ nearly -= do_div(t, object_set_size);
+
+ while (length && offset < nearly) {
+ loff_t size = length;
+ ret = ceph_zero_partial_object(inode, offset, &size);
+ if (ret < 0)
+ return ret;
+ offset += size;
+ length -= size;
+ }
+ while (length >= object_set_size) {
+ int i;
+ loff_t pos = offset;
+ for (i = 0; i < stripe_count; ++i) {
+ ret = ceph_zero_partial_object(inode, pos, NULL);
+ if (ret < 0)
+ return ret;
+ pos += stripe_unit;
+ }
+ offset += object_set_size;
+ length -= object_set_size;
+ }
+ while (length) {
+ loff_t size = length;
+ ret = ceph_zero_partial_object(inode, offset, &size);
+ if (ret < 0)
+ return ret;
+ offset += size;
+ length -= size;
+ }
+ return ret;
+}
+
+static long ceph_fallocate(struct file *file, int mode,
+ loff_t offset, loff_t length)
+{
+ struct ceph_file_info *fi = file->private_data;
+ struct inode *inode = file_inode(file);
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ struct ceph_osd_client *osdc =
+ &ceph_inode_to_client(inode)->client->osdc;
+ int want, got = 0;
+ int dirty;
+ int ret = 0;
+ loff_t endoff = 0;
+ loff_t size;
+
+ if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
+ return -EOPNOTSUPP;
+
+ if (!S_ISREG(inode->i_mode))
+ return -EOPNOTSUPP;
+
+ mutex_lock(&inode->i_mutex);
+
+ if (ceph_snap(inode) != CEPH_NOSNAP) {
+ ret = -EROFS;
+ goto unlock;
+ }
+
+ if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL) &&
+ !(mode & FALLOC_FL_PUNCH_HOLE)) {
+ ret = -ENOSPC;
+ goto unlock;
+ }
+
+ if (ci->i_inline_version != CEPH_INLINE_NONE) {
+ ret = ceph_uninline_data(file, NULL);
+ if (ret < 0)
+ goto unlock;
+ }
+
+ size = i_size_read(inode);
+ if (!(mode & FALLOC_FL_KEEP_SIZE))
+ endoff = offset + length;
+
+ if (fi->fmode & CEPH_FILE_MODE_LAZY)
+ want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
+ else
+ want = CEPH_CAP_FILE_BUFFER;
+
+ ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, endoff, &got, NULL);
+ if (ret < 0)
+ goto unlock;
+
+ if (mode & FALLOC_FL_PUNCH_HOLE) {
+ if (offset < size)
+ ceph_zero_pagecache_range(inode, offset, length);
+ ret = ceph_zero_objects(inode, offset, length);
+ } else if (endoff > size) {
+ truncate_pagecache_range(inode, size, -1);
+ if (ceph_inode_set_size(inode, endoff))
+ ceph_check_caps(ceph_inode(inode),
+ CHECK_CAPS_AUTHONLY, NULL);
+ }
+
+ if (!ret) {
+ spin_lock(&ci->i_ceph_lock);
+ ci->i_inline_version = CEPH_INLINE_NONE;
+ dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
+ spin_unlock(&ci->i_ceph_lock);
+ if (dirty)
+ __mark_inode_dirty(inode, dirty);
+ }
+
+ ceph_put_cap_refs(ci, got);
+unlock:
+ mutex_unlock(&inode->i_mutex);
+ return ret;
+}
+
+const struct file_operations ceph_file_fops = {
+ .open = ceph_open,
+ .release = ceph_release,
+ .llseek = ceph_llseek,
+ .read_iter = ceph_read_iter,
+ .write_iter = ceph_write_iter,
+ .mmap = ceph_mmap,
+ .fsync = ceph_fsync,
+ .lock = ceph_lock,
+ .flock = ceph_flock,
+ .splice_read = generic_file_splice_read,
+ .splice_write = iter_file_splice_write,
+ .unlocked_ioctl = ceph_ioctl,
+ .compat_ioctl = ceph_ioctl,
+ .fallocate = ceph_fallocate,
+};
+