#include <trace/events/fscache.h>
#include "internal.h"
+struct cachefiles_kiocb {
+ struct kiocb iocb;
+ refcount_t ki_refcnt;
+ loff_t start;
+ union {
+ size_t skipped;
+ size_t len;
+ };
+ struct cachefiles_object *object;
+ netfs_io_terminated_t term_func;
+ void *term_func_priv;
+ bool was_async;
+ unsigned int inval_counter; /* Copy of cookie->inval_counter */
+ u64 b_writing;
+};
+
+static inline void cachefiles_put_kiocb(struct cachefiles_kiocb *ki)
+{
+ if (refcount_dec_and_test(&ki->ki_refcnt)) {
+ cachefiles_put_object(ki->object, cachefiles_obj_put_ioreq);
+ fput(ki->iocb.ki_filp);
+ kfree(ki);
+ }
+}
+
+/*
+ * Handle completion of a read from the cache.
+ */
+static void cachefiles_read_complete(struct kiocb *iocb, long ret)
+{
+ struct cachefiles_kiocb *ki = container_of(iocb, struct cachefiles_kiocb, iocb);
+ struct inode *inode = file_inode(ki->iocb.ki_filp);
+
+ _enter("%ld", ret);
+
+ if (ret < 0)
+ trace_cachefiles_io_error(ki->object, inode, ret,
+ cachefiles_trace_read_error);
+
+ if (ki->term_func) {
+ if (ret >= 0) {
+ if (ki->object->cookie->inval_counter == ki->inval_counter)
+ ki->skipped += ret;
+ else
+ ret = -ESTALE;
+ }
+
+ ki->term_func(ki->term_func_priv, ret, ki->was_async);
+ }
+
+ cachefiles_put_kiocb(ki);
+}
+
+/*
+ * Initiate a read from the cache.
+ */
+static int cachefiles_read(struct netfs_cache_resources *cres,
+ loff_t start_pos,
+ struct iov_iter *iter,
+ enum netfs_read_from_hole read_hole,
+ netfs_io_terminated_t term_func,
+ void *term_func_priv)
+{
+ struct cachefiles_object *object;
+ struct cachefiles_kiocb *ki;
+ struct file *file;
+ unsigned int old_nofs;
+ ssize_t ret = -ENOBUFS;
+ size_t len = iov_iter_count(iter), skipped = 0;
+
+ if (!fscache_wait_for_operation(cres, FSCACHE_WANT_READ))
+ goto presubmission_error;
+
+ fscache_count_read();
+ object = cachefiles_cres_object(cres);
+ file = cachefiles_cres_file(cres);
+
+ _enter("%pD,%li,%llx,%zx/%llx",
+ file, file_inode(file)->i_ino, start_pos, len,
+ i_size_read(file_inode(file)));
+
+ /* If the caller asked us to seek for data before doing the read, then
+ * we should do that now. If we find a gap, we fill it with zeros.
+ */
+ if (read_hole != NETFS_READ_HOLE_IGNORE) {
+ loff_t off = start_pos, off2;
+
+ off2 = cachefiles_inject_read_error();
+ if (off2 == 0)
+ off2 = vfs_llseek(file, off, SEEK_DATA);
+ if (off2 < 0 && off2 >= (loff_t)-MAX_ERRNO && off2 != -ENXIO) {
+ skipped = 0;
+ ret = off2;
+ goto presubmission_error;
+ }
+
+ if (off2 == -ENXIO || off2 >= start_pos + len) {
+ /* The region is beyond the EOF or there's no more data
+ * in the region, so clear the rest of the buffer and
+ * return success.
+ */
+ ret = -ENODATA;
+ if (read_hole == NETFS_READ_HOLE_FAIL)
+ goto presubmission_error;
+
+ iov_iter_zero(len, iter);
+ skipped = len;
+ ret = 0;
+ goto presubmission_error;
+ }
+
+ skipped = off2 - off;
+ iov_iter_zero(skipped, iter);
+ }
+
+ ret = -ENOMEM;
+ ki = kzalloc(sizeof(struct cachefiles_kiocb), GFP_KERNEL);
+ if (!ki)
+ goto presubmission_error;
+
+ refcount_set(&ki->ki_refcnt, 2);
+ ki->iocb.ki_filp = file;
+ ki->iocb.ki_pos = start_pos + skipped;
+ ki->iocb.ki_flags = IOCB_DIRECT;
+ ki->iocb.ki_hint = ki_hint_validate(file_write_hint(file));
+ ki->iocb.ki_ioprio = get_current_ioprio();
+ ki->skipped = skipped;
+ ki->object = object;
+ ki->inval_counter = cres->inval_counter;
+ ki->term_func = term_func;
+ ki->term_func_priv = term_func_priv;
+ ki->was_async = true;
+
+ if (ki->term_func)
+ ki->iocb.ki_complete = cachefiles_read_complete;
+
+ get_file(ki->iocb.ki_filp);
+ cachefiles_grab_object(object, cachefiles_obj_get_ioreq);
+
+ trace_cachefiles_read(object, file_inode(file), ki->iocb.ki_pos, len - skipped);
+ old_nofs = memalloc_nofs_save();
+ ret = cachefiles_inject_read_error();
+ if (ret == 0)
+ ret = vfs_iocb_iter_read(file, &ki->iocb, iter);
+ memalloc_nofs_restore(old_nofs);
+ switch (ret) {
+ case -EIOCBQUEUED:
+ goto in_progress;
+
+ case -ERESTARTSYS:
+ case -ERESTARTNOINTR:
+ case -ERESTARTNOHAND:
+ case -ERESTART_RESTARTBLOCK:
+ /* There's no easy way to restart the syscall since other AIO's
+ * may be already running. Just fail this IO with EINTR.
+ */
+ ret = -EINTR;
+ fallthrough;
+ default:
+ ki->was_async = false;
+ cachefiles_read_complete(&ki->iocb, ret);
+ if (ret > 0)
+ ret = 0;
+ break;
+ }
+
+in_progress:
+ cachefiles_put_kiocb(ki);
+ _leave(" = %zd", ret);
+ return ret;
+
+presubmission_error:
+ if (term_func)
+ term_func(term_func_priv, ret < 0 ? ret : skipped, false);
+ return ret;
+}
+
+/*
+ * Handle completion of a write to the cache.
+ */
+static void cachefiles_write_complete(struct kiocb *iocb, long ret)
+{
+ struct cachefiles_kiocb *ki = container_of(iocb, struct cachefiles_kiocb, iocb);
+ struct cachefiles_object *object = ki->object;
+ struct inode *inode = file_inode(ki->iocb.ki_filp);
+
+ _enter("%ld", ret);
+
+ /* Tell lockdep we inherited freeze protection from submission thread */
+ __sb_writers_acquired(inode->i_sb, SB_FREEZE_WRITE);
+ __sb_end_write(inode->i_sb, SB_FREEZE_WRITE);
+
+ if (ret < 0)
+ trace_cachefiles_io_error(object, inode, ret,
+ cachefiles_trace_write_error);
+
+ atomic_long_sub(ki->b_writing, &object->volume->cache->b_writing);
+ set_bit(FSCACHE_COOKIE_HAVE_DATA, &object->cookie->flags);
+ if (ki->term_func)
+ ki->term_func(ki->term_func_priv, ret, ki->was_async);
+ cachefiles_put_kiocb(ki);
+}
+
+/*
+ * Initiate a write to the cache.
+ */
+static int cachefiles_write(struct netfs_cache_resources *cres,
+ loff_t start_pos,
+ struct iov_iter *iter,
+ netfs_io_terminated_t term_func,
+ void *term_func_priv)
+{
+ struct cachefiles_object *object;
+ struct cachefiles_cache *cache;
+ struct cachefiles_kiocb *ki;
+ struct inode *inode;
+ struct file *file;
+ unsigned int old_nofs;
+ ssize_t ret = -ENOBUFS;
+ size_t len = iov_iter_count(iter);
+
+ if (!fscache_wait_for_operation(cres, FSCACHE_WANT_WRITE))
+ goto presubmission_error;
+ fscache_count_write();
+ object = cachefiles_cres_object(cres);
+ cache = object->volume->cache;
+ file = cachefiles_cres_file(cres);
+
+ _enter("%pD,%li,%llx,%zx/%llx",
+ file, file_inode(file)->i_ino, start_pos, len,
+ i_size_read(file_inode(file)));
+
+ ret = -ENOMEM;
+ ki = kzalloc(sizeof(struct cachefiles_kiocb), GFP_KERNEL);
+ if (!ki)
+ goto presubmission_error;
+
+ refcount_set(&ki->ki_refcnt, 2);
+ ki->iocb.ki_filp = file;
+ ki->iocb.ki_pos = start_pos;
+ ki->iocb.ki_flags = IOCB_DIRECT | IOCB_WRITE;
+ ki->iocb.ki_hint = ki_hint_validate(file_write_hint(file));
+ ki->iocb.ki_ioprio = get_current_ioprio();
+ ki->object = object;
+ ki->inval_counter = cres->inval_counter;
+ ki->start = start_pos;
+ ki->len = len;
+ ki->term_func = term_func;
+ ki->term_func_priv = term_func_priv;
+ ki->was_async = true;
+ ki->b_writing = (len + (1 << cache->bshift)) >> cache->bshift;
+
+ if (ki->term_func)
+ ki->iocb.ki_complete = cachefiles_write_complete;
+ atomic_long_add(ki->b_writing, &cache->b_writing);
+
+ /* Open-code file_start_write here to grab freeze protection, which
+ * will be released by another thread in aio_complete_rw(). Fool
+ * lockdep by telling it the lock got released so that it doesn't
+ * complain about the held lock when we return to userspace.
+ */
+ inode = file_inode(file);
+ __sb_start_write(inode->i_sb, SB_FREEZE_WRITE);
+ __sb_writers_release(inode->i_sb, SB_FREEZE_WRITE);
+
+ get_file(ki->iocb.ki_filp);
+ cachefiles_grab_object(object, cachefiles_obj_get_ioreq);
+
+ trace_cachefiles_write(object, inode, ki->iocb.ki_pos, len);
+ old_nofs = memalloc_nofs_save();
+ ret = cachefiles_inject_write_error();
+ if (ret == 0)
+ ret = vfs_iocb_iter_write(file, &ki->iocb, iter);
+ memalloc_nofs_restore(old_nofs);
+ switch (ret) {
+ case -EIOCBQUEUED:
+ goto in_progress;
+
+ case -ERESTARTSYS:
+ case -ERESTARTNOINTR:
+ case -ERESTARTNOHAND:
+ case -ERESTART_RESTARTBLOCK:
+ /* There's no easy way to restart the syscall since other AIO's
+ * may be already running. Just fail this IO with EINTR.
+ */
+ ret = -EINTR;
+ fallthrough;
+ default:
+ ki->was_async = false;
+ cachefiles_write_complete(&ki->iocb, ret);
+ if (ret > 0)
+ ret = 0;
+ break;
+ }
+
+in_progress:
+ cachefiles_put_kiocb(ki);
+ _leave(" = %zd", ret);
+ return ret;
+
+presubmission_error:
+ if (term_func)
+ term_func(term_func_priv, ret, false);
+ return ret;
+}
+
+/*
+ * Prepare a read operation, shortening it to a cached/uncached
+ * boundary as appropriate.
+ */
+static enum netfs_read_source cachefiles_prepare_read(struct netfs_read_subrequest *subreq,
+ loff_t i_size)
+{
+ enum cachefiles_prepare_read_trace why;
+ struct netfs_read_request *rreq = subreq->rreq;
+ struct netfs_cache_resources *cres = &rreq->cache_resources;
+ struct cachefiles_object *object;
+ struct cachefiles_cache *cache;
+ struct fscache_cookie *cookie = fscache_cres_cookie(cres);
+ const struct cred *saved_cred;
+ struct file *file = cachefiles_cres_file(cres);
+ enum netfs_read_source ret = NETFS_DOWNLOAD_FROM_SERVER;
+ loff_t off, to;
+ ino_t ino = file ? file_inode(file)->i_ino : 0;
+
+ _enter("%zx @%llx/%llx", subreq->len, subreq->start, i_size);
+
+ if (subreq->start >= i_size) {
+ ret = NETFS_FILL_WITH_ZEROES;
+ why = cachefiles_trace_read_after_eof;
+ goto out_no_object;
+ }
+
+ if (test_bit(FSCACHE_COOKIE_NO_DATA_TO_READ, &cookie->flags)) {
+ __set_bit(NETFS_SREQ_WRITE_TO_CACHE, &subreq->flags);
+ why = cachefiles_trace_read_no_data;
+ goto out_no_object;
+ }
+
+ /* The object and the file may be being created in the background. */
+ if (!file) {
+ why = cachefiles_trace_read_no_file;
+ if (!fscache_wait_for_operation(cres, FSCACHE_WANT_READ))
+ goto out_no_object;
+ file = cachefiles_cres_file(cres);
+ if (!file)
+ goto out_no_object;
+ ino = file_inode(file)->i_ino;
+ }
+
+ object = cachefiles_cres_object(cres);
+ cache = object->volume->cache;
+ cachefiles_begin_secure(cache, &saved_cred);
+
+ off = cachefiles_inject_read_error();
+ if (off == 0)
+ off = vfs_llseek(file, subreq->start, SEEK_DATA);
+ if (off < 0 && off >= (loff_t)-MAX_ERRNO) {
+ if (off == (loff_t)-ENXIO) {
+ why = cachefiles_trace_read_seek_nxio;
+ goto download_and_store;
+ }
+ trace_cachefiles_io_error(object, file_inode(file), off,
+ cachefiles_trace_seek_error);
+ why = cachefiles_trace_read_seek_error;
+ goto out;
+ }
+
+ if (off >= subreq->start + subreq->len) {
+ why = cachefiles_trace_read_found_hole;
+ goto download_and_store;
+ }
+
+ if (off > subreq->start) {
+ off = round_up(off, cache->bsize);
+ subreq->len = off - subreq->start;
+ why = cachefiles_trace_read_found_part;
+ goto download_and_store;
+ }
+
+ to = cachefiles_inject_read_error();
+ if (to == 0)
+ to = vfs_llseek(file, subreq->start, SEEK_HOLE);
+ if (to < 0 && to >= (loff_t)-MAX_ERRNO) {
+ trace_cachefiles_io_error(object, file_inode(file), to,
+ cachefiles_trace_seek_error);
+ why = cachefiles_trace_read_seek_error;
+ goto out;
+ }
+
+ if (to < subreq->start + subreq->len) {
+ if (subreq->start + subreq->len >= i_size)
+ to = round_up(to, cache->bsize);
+ else
+ to = round_down(to, cache->bsize);
+ subreq->len = to - subreq->start;
+ }
+
+ why = cachefiles_trace_read_have_data;
+ ret = NETFS_READ_FROM_CACHE;
+ goto out;
+
+download_and_store:
+ __set_bit(NETFS_SREQ_WRITE_TO_CACHE, &subreq->flags);
+out:
+ cachefiles_end_secure(cache, saved_cred);
+out_no_object:
+ trace_cachefiles_prep_read(subreq, ret, why, ino);
+ return ret;
+}
+
+/*
+ * Prepare for a write to occur.
+ */
+static int __cachefiles_prepare_write(struct netfs_cache_resources *cres,
+ loff_t *_start, size_t *_len, loff_t i_size,
+ bool no_space_allocated_yet)
+{
+ struct cachefiles_object *object = cachefiles_cres_object(cres);
+ struct cachefiles_cache *cache = object->volume->cache;
+ struct file *file = cachefiles_cres_file(cres);
+ loff_t start = *_start, pos;
+ size_t len = *_len, down;
+ int ret;
+
+ /* Round to DIO size */
+ down = start - round_down(start, PAGE_SIZE);
+ *_start = start - down;
+ *_len = round_up(down + len, PAGE_SIZE);
+
+ /* We need to work out whether there's sufficient disk space to perform
+ * the write - but we can skip that check if we have space already
+ * allocated.
+ */
+ if (no_space_allocated_yet)
+ goto check_space;
+
+ pos = cachefiles_inject_read_error();
+ if (pos == 0)
+ pos = vfs_llseek(file, *_start, SEEK_DATA);
+ if (pos < 0 && pos >= (loff_t)-MAX_ERRNO) {
+ if (pos == -ENXIO)
+ goto check_space; /* Unallocated tail */
+ trace_cachefiles_io_error(object, file_inode(file), pos,
+ cachefiles_trace_seek_error);
+ return pos;
+ }
+ if ((u64)pos >= (u64)*_start + *_len)
+ goto check_space; /* Unallocated region */
+
+ /* We have a block that's at least partially filled - if we're low on
+ * space, we need to see if it's fully allocated. If it's not, we may
+ * want to cull it.
+ */
+ if (cachefiles_has_space(cache, 0, *_len / PAGE_SIZE) == 0)
+ return 0; /* Enough space to simply overwrite the whole block */
+
+ pos = cachefiles_inject_read_error();
+ if (pos == 0)
+ pos = vfs_llseek(file, *_start, SEEK_HOLE);
+ if (pos < 0 && pos >= (loff_t)-MAX_ERRNO) {
+ trace_cachefiles_io_error(object, file_inode(file), pos,
+ cachefiles_trace_seek_error);
+ return pos;
+ }
+ if ((u64)pos >= (u64)*_start + *_len)
+ return 0; /* Fully allocated */
+
+ /* Partially allocated, but insufficient space: cull. */
+ ret = cachefiles_inject_remove_error();
+ if (ret == 0)
+ ret = vfs_fallocate(file, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
+ *_start, *_len);
+ if (ret < 0) {
+ trace_cachefiles_io_error(object, file_inode(file), ret,
+ cachefiles_trace_fallocate_error);
+ cachefiles_io_error_obj(object,
+ "CacheFiles: fallocate failed (%d)\n", ret);
+ ret = -EIO;
+ }
+
+ return ret;
+
+check_space:
+ return cachefiles_has_space(cache, 0, *_len / PAGE_SIZE);
+}
+
+static int cachefiles_prepare_write(struct netfs_cache_resources *cres,
+ loff_t *_start, size_t *_len, loff_t i_size,
+ bool no_space_allocated_yet)
+{
+ struct cachefiles_object *object = cachefiles_cres_object(cres);
+ struct cachefiles_cache *cache = object->volume->cache;
+ const struct cred *saved_cred;
+ int ret;
+
+ if (!cachefiles_cres_file(cres)) {
+ if (!fscache_wait_for_operation(cres, FSCACHE_WANT_WRITE))
+ return -ENOBUFS;
+ if (!cachefiles_cres_file(cres))
+ return -ENOBUFS;
+ }
+
+ cachefiles_begin_secure(cache, &saved_cred);
+ ret = __cachefiles_prepare_write(cres, _start, _len, i_size,
+ no_space_allocated_yet);
+ cachefiles_end_secure(cache, saved_cred);
+ return ret;
+}
+
/*
* Clean up an operation.
*/
static const struct netfs_cache_ops cachefiles_netfs_cache_ops = {
.end_operation = cachefiles_end_operation,
+ .read = cachefiles_read,
+ .write = cachefiles_write,
+ .prepare_read = cachefiles_prepare_read,
+ .prepare_write = cachefiles_prepare_write,
};
/*
cachefiles_trunc_shrink,
};
+enum cachefiles_prepare_read_trace {
+ cachefiles_trace_read_after_eof,
+ cachefiles_trace_read_found_hole,
+ cachefiles_trace_read_found_part,
+ cachefiles_trace_read_have_data,
+ cachefiles_trace_read_no_data,
+ cachefiles_trace_read_no_file,
+ cachefiles_trace_read_seek_error,
+ cachefiles_trace_read_seek_nxio,
+};
+
enum cachefiles_error_trace {
cachefiles_trace_fallocate_error,
cachefiles_trace_getxattr_error,
EM(cachefiles_trunc_expand_tmpfile, "EXPTMP") \
E_(cachefiles_trunc_shrink, "SHRINK")
+#define cachefiles_prepare_read_traces \
+ EM(cachefiles_trace_read_after_eof, "after-eof ") \
+ EM(cachefiles_trace_read_found_hole, "found-hole") \
+ EM(cachefiles_trace_read_found_part, "found-part") \
+ EM(cachefiles_trace_read_have_data, "have-data ") \
+ EM(cachefiles_trace_read_no_data, "no-data ") \
+ EM(cachefiles_trace_read_no_file, "no-file ") \
+ EM(cachefiles_trace_read_seek_error, "seek-error") \
+ E_(cachefiles_trace_read_seek_nxio, "seek-enxio")
+
#define cachefiles_error_traces \
EM(cachefiles_trace_fallocate_error, "fallocate") \
EM(cachefiles_trace_getxattr_error, "getxattr") \
cachefiles_obj_ref_traces;
cachefiles_coherency_traces;
cachefiles_trunc_traces;
+cachefiles_prepare_read_traces;
cachefiles_error_traces;
/*
__entry->content)
);
+TRACE_EVENT(cachefiles_prep_read,
+ TP_PROTO(struct netfs_read_subrequest *sreq,
+ enum netfs_read_source source,
+ enum cachefiles_prepare_read_trace why,
+ ino_t cache_inode),
+
+ TP_ARGS(sreq, source, why, cache_inode),
+
+ TP_STRUCT__entry(
+ __field(unsigned int, rreq )
+ __field(unsigned short, index )
+ __field(unsigned short, flags )
+ __field(enum netfs_read_source, source )
+ __field(enum cachefiles_prepare_read_trace, why )
+ __field(size_t, len )
+ __field(loff_t, start )
+ __field(unsigned int, netfs_inode )
+ __field(unsigned int, cache_inode )
+ ),
+
+ TP_fast_assign(
+ __entry->rreq = sreq->rreq->debug_id;
+ __entry->index = sreq->debug_index;
+ __entry->flags = sreq->flags;
+ __entry->source = source;
+ __entry->why = why;
+ __entry->len = sreq->len;
+ __entry->start = sreq->start;
+ __entry->netfs_inode = sreq->rreq->inode->i_ino;
+ __entry->cache_inode = cache_inode;
+ ),
+
+ TP_printk("R=%08x[%u] %s %s f=%02x s=%llx %zx ni=%x b=%x",
+ __entry->rreq, __entry->index,
+ __print_symbolic(__entry->source, netfs_sreq_sources),
+ __print_symbolic(__entry->why, cachefiles_prepare_read_traces),
+ __entry->flags,
+ __entry->start, __entry->len,
+ __entry->netfs_inode, __entry->cache_inode)
+ );
+
+TRACE_EVENT(cachefiles_read,
+ TP_PROTO(struct cachefiles_object *obj,
+ struct inode *backer,
+ loff_t start,
+ size_t len),
+
+ TP_ARGS(obj, backer, start, len),
+
+ TP_STRUCT__entry(
+ __field(unsigned int, obj )
+ __field(unsigned int, backer )
+ __field(size_t, len )
+ __field(loff_t, start )
+ ),
+
+ TP_fast_assign(
+ __entry->obj = obj->debug_id;
+ __entry->backer = backer->i_ino;
+ __entry->start = start;
+ __entry->len = len;
+ ),
+
+ TP_printk("o=%08x b=%08x s=%llx l=%zx",
+ __entry->obj,
+ __entry->backer,
+ __entry->start,
+ __entry->len)
+ );
+
+TRACE_EVENT(cachefiles_write,
+ TP_PROTO(struct cachefiles_object *obj,
+ struct inode *backer,
+ loff_t start,
+ size_t len),
+
+ TP_ARGS(obj, backer, start, len),
+
+ TP_STRUCT__entry(
+ __field(unsigned int, obj )
+ __field(unsigned int, backer )
+ __field(size_t, len )
+ __field(loff_t, start )
+ ),
+
+ TP_fast_assign(
+ __entry->obj = obj->debug_id;
+ __entry->backer = backer->i_ino;
+ __entry->start = start;
+ __entry->len = len;
+ ),
+
+ TP_printk("o=%08x b=%08x s=%llx l=%zx",
+ __entry->obj,
+ __entry->backer,
+ __entry->start,
+ __entry->len)
+ );
+
TRACE_EVENT(cachefiles_trunc,
TP_PROTO(struct cachefiles_object *obj, struct inode *backer,
loff_t from, loff_t to, enum cachefiles_trunc_trace why),
projects / users / jedix / linux-maple.git / commitdiff