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file.c
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// SPDX-License-Identifier: GPL-2.0
#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"
static __le32 ceph_flags_sys2wire(u32 flags)
{
u32 wire_flags = 0;
switch (flags & O_ACCMODE) {
case O_RDONLY:
wire_flags |= CEPH_O_RDONLY;
break;
case O_WRONLY:
wire_flags |= CEPH_O_WRONLY;
break;
case O_RDWR:
wire_flags |= CEPH_O_RDWR;
break;
}
#define ceph_sys2wire(a) if (flags & a) { wire_flags |= CEPH_##a; flags &= ~a; }
ceph_sys2wire(O_CREAT);
ceph_sys2wire(O_EXCL);
ceph_sys2wire(O_TRUNC);
ceph_sys2wire(O_DIRECTORY);
ceph_sys2wire(O_NOFOLLOW);
#undef ceph_sys2wire
if (flags)
dout("unused open flags: %x", flags);
return cpu_to_le32(wire_flags);
}
/*
* 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.
*/
/*
* Calculate the length sum of direct io vectors that can
* be combined into one page vector.
*/
static size_t dio_get_pagev_size(const struct iov_iter *it)
{
const struct iovec *iov = it->iov;
const struct iovec *iovend = iov + it->nr_segs;
size_t size;
size = iov->iov_len - it->iov_offset;
/*
* An iov can be page vectored when both the current tail
* and the next base are page aligned.
*/
while (PAGE_ALIGNED((iov->iov_base + iov->iov_len)) &&
(++iov < iovend && PAGE_ALIGNED((iov->iov_base)))) {
size += iov->iov_len;
}
dout("dio_get_pagevlen len = %zu\n", size);
return size;
}
/*
* Allocate a page vector based on (@it, @nbytes).
* The return value is the tuple describing a page vector,
* that is (@pages, @page_align, @num_pages).
*/
static struct page **
dio_get_pages_alloc(const struct iov_iter *it, size_t nbytes,
size_t *page_align, int *num_pages)
{
struct iov_iter tmp_it = *it;
size_t align;
struct page **pages;
int ret = 0, idx, npages;
align = (unsigned long)(it->iov->iov_base + it->iov_offset) &
(PAGE_SIZE - 1);
npages = calc_pages_for(align, nbytes);
pages = kvmalloc(sizeof(*pages) * npages, GFP_KERNEL);
if (!pages)
return ERR_PTR(-ENOMEM);
for (idx = 0; idx < npages; ) {
size_t start;
ret = iov_iter_get_pages(&tmp_it, pages + idx, nbytes,
npages - idx, &start);
if (ret < 0)
goto fail;
iov_iter_advance(&tmp_it, ret);
nbytes -= ret;
idx += (ret + start + PAGE_SIZE - 1) / PAGE_SIZE;
}
BUG_ON(nbytes != 0);
*num_pages = npages;
*page_align = align;
dout("dio_get_pages_alloc: got %d pages align %zu\n", npages, align);
return pages;
fail:
ceph_put_page_vector(pages, idx, false);
return ERR_PTR(ret);
}
/*
* 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 = ceph_flags_sys2wire(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;
switch (inode->i_mode & S_IFMT) {
case S_IFREG:
ceph_fscache_register_inode_cookie(inode);
ceph_fscache_file_set_cookie(inode, file);
case S_IFDIR:
dout("init_file %p %p 0%o (regular)\n", inode, file,
inode->i_mode);
cf = kmem_cache_zalloc(ceph_file_cachep, GFP_KERNEL);
if (!cf) {
ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
return -ENOMEM;
}
cf->fmode = fmode;
spin_lock_init(&cf->rw_contexts_lock);
INIT_LIST_HEAD(&cf->rw_contexts);
cf->next_offset = 2;
cf->readdir_cache_idx = -1;
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;
}
/*
* try renew caps after session gets killed.
*/
int ceph_renew_caps(struct inode *inode)
{
struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
struct ceph_inode_info *ci = ceph_inode(inode);
struct ceph_mds_request *req;
int err, flags, wanted;
spin_lock(&ci->i_ceph_lock);
wanted = __ceph_caps_file_wanted(ci);
if (__ceph_is_any_real_caps(ci) &&
(!(wanted & CEPH_CAP_ANY_WR) || ci->i_auth_cap)) {
int issued = __ceph_caps_issued(ci, NULL);
spin_unlock(&ci->i_ceph_lock);
dout("renew caps %p want %s issued %s updating mds_wanted\n",
inode, ceph_cap_string(wanted), ceph_cap_string(issued));
ceph_check_caps(ci, 0, NULL);
return 0;
}
spin_unlock(&ci->i_ceph_lock);
flags = 0;
if ((wanted & CEPH_CAP_FILE_RD) && (wanted & CEPH_CAP_FILE_WR))
flags = O_RDWR;
else if (wanted & CEPH_CAP_FILE_RD)
flags = O_RDONLY;
else if (wanted & CEPH_CAP_FILE_WR)
flags = O_WRONLY;
#ifdef O_LAZY
if (wanted & CEPH_CAP_FILE_LAZYIO)
flags |= O_LAZY;
#endif
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;
req->r_fmode = -1;
err = ceph_mdsc_do_request(mdsc, NULL, req);
ceph_mdsc_put_request(req);
out:
dout("renew caps %p open result=%d\n", inode, err);
return err < 0 ? err : 0;
}
/*
* 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;
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, true);
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;
err = ceph_mdsc_do_request(mdsc, NULL, req);
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 mask;
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;
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 | CEPH_CAP_AUTH_EXCL;
req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
if (acls.pagelist) {
req->r_pagelist = acls.pagelist;
acls.pagelist = NULL;
}
}
mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
if (ceph_security_xattr_wanted(dir))
mask |= CEPH_CAP_XATTR_SHARED;
req->r_args.open.mask = cpu_to_le32(mask);
req->r_parent = dir;
set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
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 ((flags & O_CREAT) && !req->r_reply_info.head->is_dentry)
err = ceph_handle_notrace_create(dir, dentry);
if (d_in_lookup(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);
WARN_ON(!list_empty(&cf->rw_contexts));
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 {
HAVE_RETRIED = 1,
CHECK_EOF = 2,
READ_INLINE = 3,
};
/*
* 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 pos, u64 len,
struct page **pages, int num_pages,
int page_align, int *checkeof)
{
struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
struct ceph_inode_info *ci = ceph_inode(inode);
u64 this_len;
loff_t i_size;
int page_idx;
int ret, read = 0;
bool hit_stripe, was_short;
/*
* we may need to do multiple reads. not atomic, unfortunately.
*/
more:
this_len = len;
page_idx = (page_align + read) >> PAGE_SHIFT;
ret = ceph_osdc_readpages(&fsc->client->osdc, ceph_vino(inode),
&ci->i_layout, pos, &this_len,
ci->i_truncate_seq, ci->i_truncate_size,
pages + page_idx, num_pages - page_idx,
((page_align + read) & ~PAGE_MASK));
if (ret == -ENOENT)
ret = 0;
hit_stripe = this_len < len;
was_short = ret >= 0 && ret < this_len;
dout("striped_read %llu~%llu (read %u) got %d%s%s\n", pos, len, read,
ret, hit_stripe ? " HITSTRIPE" : "", was_short ? " SHORT" : "");
i_size = i_size_read(inode);
if (ret >= 0) {
if (was_short && (pos + ret < i_size)) {
int zlen = min(this_len - ret, i_size - pos - ret);
int zoff = page_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;
}
read += ret;
pos += ret;
len -= ret;
/* hit stripe and need continue*/
if (len && hit_stripe && pos < i_size)
goto more;
}
if (read > 0) {
ret = read;
/* did we bounce off eof? */
if (pos + len > 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 *to,
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;
ssize_t ret;
size_t len = iov_iter_count(to);
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 (unlikely(to->type & ITER_PIPE)) {
size_t page_off;
ret = iov_iter_get_pages_alloc(to, &pages, len,
&page_off);
if (ret <= 0)
return -ENOMEM;
num_pages = DIV_ROUND_UP(ret + page_off, PAGE_SIZE);
ret = striped_read(inode, off, ret, pages, num_pages,
page_off, checkeof);
if (ret > 0) {
iov_iter_advance(to, ret);
off += ret;
} else {
iov_iter_advance(to, 0);
}
ceph_put_page_vector(pages, num_pages, false);
} else {
num_pages = calc_pages_for(off, len);
pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
if (IS_ERR(pages))
return PTR_ERR(pages);
ret = striped_read(inode, off, len, pages, num_pages,
(off & ~PAGE_MASK), checkeof);
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, left,
PAGE_SIZE - page_off);
l = copy_page_to_iter(pages[k++], page_off,
copy, to);
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 %zd\n", ret);
return ret;
}
struct ceph_aio_request {
struct kiocb *iocb;
size_t total_len;
bool write;
bool should_dirty;
int error;
struct list_head osd_reqs;
unsigned num_reqs;
atomic_t pending_reqs;
struct timespec mtime;
struct ceph_cap_flush *prealloc_cf;
};
struct ceph_aio_work {
struct work_struct work;
struct ceph_osd_request *req;
};
static void ceph_aio_retry_work(struct work_struct *work);
static void ceph_aio_complete(struct inode *inode,
struct ceph_aio_request *aio_req)
{
struct ceph_inode_info *ci = ceph_inode(inode);
int ret;
if (!atomic_dec_and_test(&aio_req->pending_reqs))
return;
ret = aio_req->error;
if (!ret)
ret = aio_req->total_len;
dout("ceph_aio_complete %p rc %d\n", inode, ret);
if (ret >= 0 && aio_req->write) {
int dirty;
loff_t endoff = aio_req->iocb->ki_pos + aio_req->total_len;
if (endoff > i_size_read(inode)) {
if (ceph_inode_set_size(inode, endoff))
ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
}
spin_lock(&ci->i_ceph_lock);
ci->i_inline_version = CEPH_INLINE_NONE;
dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
&aio_req->prealloc_cf);
spin_unlock(&ci->i_ceph_lock);
if (dirty)
__mark_inode_dirty(inode, dirty);
}
ceph_put_cap_refs(ci, (aio_req->write ? CEPH_CAP_FILE_WR :
CEPH_CAP_FILE_RD));
aio_req->iocb->ki_complete(aio_req->iocb, ret, 0);
ceph_free_cap_flush(aio_req->prealloc_cf);
kfree(aio_req);
}
static void ceph_aio_complete_req(struct ceph_osd_request *req)
{
int rc = req->r_result;
struct inode *inode = req->r_inode;
struct ceph_aio_request *aio_req = req->r_priv;
struct ceph_osd_data *osd_data = osd_req_op_extent_osd_data(req, 0);
int num_pages = calc_pages_for((u64)osd_data->alignment,
osd_data->length);
dout("ceph_aio_complete_req %p rc %d bytes %llu\n",
inode, rc, osd_data->length);
if (rc == -EOLDSNAPC) {
struct ceph_aio_work *aio_work;
BUG_ON(!aio_req->write);
aio_work = kmalloc(sizeof(*aio_work), GFP_NOFS);
if (aio_work) {
INIT_WORK(&aio_work->work, ceph_aio_retry_work);
aio_work->req = req;
queue_work(ceph_inode_to_client(inode)->wb_wq,
&aio_work->work);
return;
}
rc = -ENOMEM;
} else if (!aio_req->write) {
if (rc == -ENOENT)
rc = 0;
if (rc >= 0 && osd_data->length > rc) {
int zoff = osd_data->alignment + rc;
int zlen = osd_data->length - rc;
/*
* If read is satisfied by single OSD request,
* it can pass EOF. Otherwise read is within
* i_size.
*/
if (aio_req->num_reqs == 1) {
loff_t i_size = i_size_read(inode);
loff_t endoff = aio_req->iocb->ki_pos + rc;
if (endoff < i_size)
zlen = min_t(size_t, zlen,
i_size - endoff);
aio_req->total_len = rc + zlen;
}
if (zlen > 0)
ceph_zero_page_vector_range(zoff, zlen,
osd_data->pages);
}
}
ceph_put_page_vector(osd_data->pages, num_pages, aio_req->should_dirty);
ceph_osdc_put_request(req);
if (rc < 0)
cmpxchg(&aio_req->error, 0, rc);
ceph_aio_complete(inode, aio_req);
return;
}
static void ceph_aio_retry_work(struct work_struct *work)
{
struct ceph_aio_work *aio_work =
container_of(work, struct ceph_aio_work, work);
struct ceph_osd_request *orig_req = aio_work->req;
struct ceph_aio_request *aio_req = orig_req->r_priv;
struct inode *inode = orig_req->r_inode;
struct ceph_inode_info *ci = ceph_inode(inode);
struct ceph_snap_context *snapc;
struct ceph_osd_request *req;
int ret;
spin_lock(&ci->i_ceph_lock);
if (__ceph_have_pending_cap_snap(ci)) {
struct ceph_cap_snap *capsnap =
list_last_entry(&ci->i_cap_snaps,
struct ceph_cap_snap,
ci_item);
snapc = ceph_get_snap_context(capsnap->context);
} else {
BUG_ON(!ci->i_head_snapc);
snapc = ceph_get_snap_context(ci->i_head_snapc);
}
spin_unlock(&ci->i_ceph_lock);
req = ceph_osdc_alloc_request(orig_req->r_osdc, snapc, 2,
false, GFP_NOFS);
if (!req) {
ret = -ENOMEM;
req = orig_req;
goto out;
}
req->r_flags = /* CEPH_OSD_FLAG_ORDERSNAP | */ CEPH_OSD_FLAG_WRITE;
ceph_oloc_copy(&req->r_base_oloc, &orig_req->r_base_oloc);
ceph_oid_copy(&req->r_base_oid, &orig_req->r_base_oid);
ret = ceph_osdc_alloc_messages(req, GFP_NOFS);
if (ret) {
ceph_osdc_put_request(req);
req = orig_req;
goto out;
}
req->r_ops[0] = orig_req->r_ops[0];
req->r_mtime = aio_req->mtime;
req->r_data_offset = req->r_ops[0].extent.offset;
ceph_osdc_put_request(orig_req);
req->r_callback = ceph_aio_complete_req;
req->r_inode = inode;
req->r_priv = aio_req;
req->r_abort_on_full = true;
ret = ceph_osdc_start_request(req->r_osdc, req, false);
out:
if (ret < 0) {
req->r_result = ret;
ceph_aio_complete_req(req);
}
ceph_put_snap_context(snapc);
kfree(aio_work);
}
static ssize_t
ceph_direct_read_write(struct kiocb *iocb, struct iov_iter *iter,
struct ceph_snap_context *snapc,
struct ceph_cap_flush **pcf)
{
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_vino vino;
struct ceph_osd_request *req;
struct page **pages;
struct ceph_aio_request *aio_req = NULL;
int num_pages = 0;
int flags;
int ret;
struct timespec mtime = current_time(inode);
size_t count = iov_iter_count(iter);
loff_t pos = iocb->ki_pos;
bool write = iov_iter_rw(iter) == WRITE;
bool should_dirty = !write && iter_is_iovec(iter);
if (write && ceph_snap(file_inode(file)) != CEPH_NOSNAP)
return -EROFS;
dout("sync_direct_%s on file %p %lld~%u snapc %p seq %lld\n",
(write ? "write" : "read"), file, pos, (unsigned)count,
snapc, snapc->seq);
ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
if (ret < 0)
return ret;
if (write) {
int ret2 = invalidate_inode_pages2_range(inode->i_mapping,
pos >> PAGE_SHIFT,
(pos + count) >> PAGE_SHIFT);
if (ret2 < 0)
dout("invalidate_inode_pages2_range returned %d\n", ret2);
flags = /* CEPH_OSD_FLAG_ORDERSNAP | */ CEPH_OSD_FLAG_WRITE;
} else {
flags = CEPH_OSD_FLAG_READ;
}
while (iov_iter_count(iter) > 0) {
u64 size = dio_get_pagev_size(iter);
size_t start = 0;
ssize_t len;
vino = ceph_vino(inode);
req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
vino, pos, &size, 0,
1,
write ? CEPH_OSD_OP_WRITE :
CEPH_OSD_OP_READ,
flags, snapc,
ci->i_truncate_seq,
ci->i_truncate_size,
false);
if (IS_ERR(req)) {
ret = PTR_ERR(req);
break;
}
if (write)
size = min_t(u64, size, fsc->mount_options->wsize);
else
size = min_t(u64, size, fsc->mount_options->rsize);
len = size;
pages = dio_get_pages_alloc(iter, len, &start, &num_pages);
if (IS_ERR(pages)) {
ceph_osdc_put_request(req);
ret = PTR_ERR(pages);
break;
}
/*
* To simplify error handling, allow AIO when IO within i_size
* or IO can be satisfied by single OSD request.
*/
if (pos == iocb->ki_pos && !is_sync_kiocb(iocb) &&
(len == count || pos + count <= i_size_read(inode))) {
aio_req = kzalloc(sizeof(*aio_req), GFP_KERNEL);
if (aio_req) {
aio_req->iocb = iocb;
aio_req->write = write;
aio_req->should_dirty = should_dirty;
INIT_LIST_HEAD(&aio_req->osd_reqs);
if (write) {
aio_req->mtime = mtime;
swap(aio_req->prealloc_cf, *pcf);
}
}
/* ignore error */
}
if (write) {
/*
* throw out any page cache pages in this range. this
* may block.
*/
truncate_inode_pages_range(inode->i_mapping, pos,
(pos+len) | (PAGE_SIZE - 1));
req->r_mtime = mtime;
}
osd_req_op_extent_osd_data_pages(req, 0, pages, len, start,
false, false);
if (aio_req) {
aio_req->total_len += len;
aio_req->num_reqs++;
atomic_inc(&aio_req->pending_reqs);
req->r_callback = ceph_aio_complete_req;
req->r_inode = inode;
req->r_priv = aio_req;
list_add_tail(&req->r_unsafe_item, &aio_req->osd_reqs);
pos += len;
iov_iter_advance(iter, len);
continue;
}
ret = ceph_osdc_start_request(req->r_osdc, req, false);
if (!ret)
ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
size = i_size_read(inode);
if (!write) {
if (ret == -ENOENT)
ret = 0;
if (ret >= 0 && ret < len && pos + ret < size) {
int zlen = min_t(size_t, len - ret,
size - pos - ret);
ceph_zero_page_vector_range(start + ret, zlen,
pages);
ret += zlen;
}
if (ret >= 0)
len = ret;
}
ceph_put_page_vector(pages, num_pages, should_dirty);
ceph_osdc_put_request(req);
if (ret < 0)
break;
pos += len;
iov_iter_advance(iter, len);
if (!write && pos >= size)
break;
if (write && pos > size) {
if (ceph_inode_set_size(inode, pos))
ceph_check_caps(ceph_inode(inode),
CHECK_CAPS_AUTHONLY,
NULL);
}
}
if (aio_req) {
LIST_HEAD(osd_reqs);
if (aio_req->num_reqs == 0) {