From: Ronnie Sahlberg Date: Sat, 18 Jun 2011 22:43:28 +0000 (+1000) Subject: Add support in read/pread to be aware of the Maximum Read size that the server X-Git-Tag: upstream/1.9.6^2~401 X-Git-Url: https://git.piment-noir.org/?a=commitdiff_plain;h=921f877be4ac27e50e60dfa855513612c1103388;p=deb_libnfs.git Add support in read/pread to be aware of the Maximum Read size that the server suggested. When a read/pread operation that is 'oversize' is issued, the read/pread command will internally chop this up into smaller chunsk and send then concurrently to the server. As replies come back from the server we add the data to a reassembly buffer and as soon as all replies have been received we invoke the callback and pass the reassembly buffer back to the application. --- diff --git a/examples/nfsclient-async.c b/examples/nfsclient-async.c index 4c7624c..b630f4e 100644 --- a/examples/nfsclient-async.c +++ b/examples/nfsclient-async.c @@ -19,7 +19,7 @@ */ #define SERVER "10.1.1.27" -#define EXPORT "/shared" +#define EXPORT "/VIRTUAL" #define NFSFILE "/BOOKS/Classics/Dracula.djvu" #define NFSDIR "/BOOKS/Classics/" @@ -138,8 +138,8 @@ void nfs_open_cb(int status, struct nfs_context *nfs, void *data, void *private_ nfsfh = data; client->nfsfh = nfsfh; printf("Got reply from server for open(%s). Handle:%p\n", NFSFILE, data); - printf("Read first 16 bytes\n"); - if (nfs_pread_async(nfs, nfsfh, 0, 16, nfs_read_cb, client) != 0) { + printf("Read first 64 bytes\n"); + if (nfs_pread_async(nfs, nfsfh, 0, 64, nfs_read_cb, client) != 0) { printf("Failed to start async nfs open\n"); exit(10); } diff --git a/lib/libnfs.c b/lib/libnfs.c index 06eea35..6687180 100644 --- a/lib/libnfs.c +++ b/lib/libnfs.c @@ -84,6 +84,19 @@ struct nfs_cb_data { int continue_int; struct nfs_fh3 fh; + + /* for multi-read/write calls. */ + int error; + int cancel; + int num_calls; + off_t start_offset, max_offset; + char *buffer; +}; + +struct nfs_mcb_data { + struct nfs_cb_data *data; + off_t offset; + size_t count; }; static int nfs_lookup_path_async_internal(struct nfs_context *nfs, struct nfs_cb_data *data, struct nfs_fh3 *fh); @@ -173,6 +186,11 @@ void free_nfs_cb_data(struct nfs_cb_data *data) data->fh.data.data_val = NULL; } + if (data->buffer != NULL) { + free(data->buffer); + data->buffer = NULL; + } + free(data); } @@ -568,7 +586,6 @@ static int nfs_lookuppath_async(struct nfs_context *nfs, const char *path, nfs_c if (data == NULL) { rpc_set_error(nfs->rpc, "out of memory: failed to allocate nfs_cb_data structure"); printf("failed to allocate memory for nfs cb data\n"); - free_nfs_cb_data(data); return -2; } bzero(data, sizeof(struct nfs_cb_data)); @@ -818,6 +835,64 @@ static void nfs_pread_cb(struct rpc_context *rpc _U_, int status, void *command_ free_nfs_cb_data(data); } +static void nfs_pread_mcb(struct rpc_context *rpc _U_, int status, void *command_data, void *private_data) +{ + struct nfs_mcb_data *mdata = private_data; + struct nfs_cb_data *data = mdata->data; + struct nfs_context *nfs = data->nfs; + READ3res *res; + + data->num_calls--; + + if (status == RPC_STATUS_ERROR) { + /* flag the failure but do not invoke callback until we have received all responses */ + data->error = 1; + } + if (status == RPC_STATUS_CANCEL) { + /* flag the cancellation but do not invoke callback until we have received all responses */ + data->cancel = 1; + } + + /* reassemble the data into the buffer */ + if (status == RPC_STATUS_SUCCESS) { + res = command_data; + if (res->status != NFS3_OK) { + rpc_set_error(nfs->rpc, "NFS: Read failed with %s(%d)", nfsstat3_to_str(res->status), nfsstat3_to_errno(res->status)); + data->error = 1; + } else { + memcpy(&data->buffer[mdata->offset], res->READ3res_u.resok.data.data_val, res->READ3res_u.resok.count); + if (data->max_offset < mdata->offset + res->READ3res_u.resok.count) { + data->max_offset = mdata->offset + res->READ3res_u.resok.count; + } + } + } + + if (data->num_calls > 0) { + /* still waiting for more replies */ + free(mdata); + return; + } + + + if (data->error != 0) { + data->cb(-EFAULT, nfs, command_data, data->private_data); + free_nfs_cb_data(data); + free(mdata); + return; + } + if (data->cancel != 0) { + data->cb(-EINTR, nfs, "Command was cancelled", data->private_data); + free_nfs_cb_data(data); + free(mdata); + return; + } + + data->nfsfh->offset = data->max_offset; + data->cb(data->max_offset - data->start_offset, nfs, data->buffer, data->private_data); + free_nfs_cb_data(data); + free(mdata); +} + int nfs_pread_async(struct nfs_context *nfs, struct nfsfh *nfsfh, off_t offset, size_t count, nfs_cb cb, void *private_data) { struct nfs_cb_data *data; @@ -826,7 +901,6 @@ int nfs_pread_async(struct nfs_context *nfs, struct nfsfh *nfsfh, off_t offset, if (data == NULL) { rpc_set_error(nfs->rpc, "out of memory: failed to allocate nfs_cb_data structure"); printf("failed to allocate memory for nfs cb data\n"); - free_nfs_cb_data(data); return -1; } bzero(data, sizeof(struct nfs_cb_data)); @@ -836,13 +910,63 @@ int nfs_pread_async(struct nfs_context *nfs, struct nfsfh *nfsfh, off_t offset, data->nfsfh = nfsfh; nfsfh->offset = offset; - if (rpc_nfs_read_async(nfs->rpc, nfs_pread_cb, &nfsfh->fh, offset, count, data) != 0) { - rpc_set_error(nfs->rpc, "RPC error: Failed to send READ call for %s", data->path); + + if (count <= nfs_get_readmax(nfs)) { + if (rpc_nfs_read_async(nfs->rpc, nfs_pread_cb, &nfsfh->fh, offset, count, data) != 0) { + rpc_set_error(nfs->rpc, "RPC error: Failed to send READ call for %s", data->path); + data->cb(-ENOMEM, nfs, rpc_get_error(nfs->rpc), data->private_data); + free_nfs_cb_data(data); + return -1; + } + return 0; + } + + /* trying to read more than maximum server read size, we has to chop it up into smaller + * reads and collect into a reassembly buffer. + * we send all reads in parallell so that performance is still good. + */ + data->start_offset = offset; + + data->buffer = malloc(count); + if (data->buffer == NULL) { + rpc_set_error(nfs->rpc, "Out-Of-Memory: Failed to allocate reassembly buffer for %d bytes", (int)count); data->cb(-ENOMEM, nfs, rpc_get_error(nfs->rpc), data->private_data); free_nfs_cb_data(data); return -1; } - return 0; + + while (count > 0) { + size_t readcount = count; + struct nfs_mcb_data *mdata; + + if (readcount > nfs_get_readmax(nfs)) { + readcount = nfs_get_readmax(nfs); + } + + mdata = malloc(sizeof(struct nfs_mcb_data)); + if (mdata == NULL) { + rpc_set_error(nfs->rpc, "out of memory: failed to allocate nfs_mcb_data structure"); + printf("failed to allocate memory for nfs mcb data\n"); + return -1; + } + bzero(mdata, sizeof(struct nfs_mcb_data)); + mdata->data = data; + mdata->offset = offset; + mdata->count = readcount; + + if (rpc_nfs_read_async(nfs->rpc, nfs_pread_mcb, &nfsfh->fh, offset, readcount, mdata) != 0) { + rpc_set_error(nfs->rpc, "RPC error: Failed to send READ call for %s", data->path); + data->cb(-ENOMEM, nfs, rpc_get_error(nfs->rpc), data->private_data); + free(mdata); + return -1; + } + + count -= readcount; + offset += readcount; + data->num_calls++; + } + + return 0; } /* @@ -896,7 +1020,6 @@ int nfs_pwrite_async(struct nfs_context *nfs, struct nfsfh *nfsfh, off_t offset, if (data == NULL) { rpc_set_error(nfs->rpc, "out of memory: failed to allocate nfs_cb_data structure"); printf("failed to allocate memory for nfs cb data\n"); - free_nfs_cb_data(data); return -1; } bzero(data, sizeof(struct nfs_cb_data)); @@ -957,7 +1080,6 @@ int nfs_fstat_async(struct nfs_context *nfs, struct nfsfh *nfsfh, nfs_cb cb, voi if (data == NULL) { rpc_set_error(nfs->rpc, "out of memory: failed to allocate nfs_cb_data structure"); printf("failed to allocate memory for nfs cb data\n"); - free_nfs_cb_data(data); return -1; } bzero(data, sizeof(struct nfs_cb_data)); @@ -1016,7 +1138,6 @@ int nfs_fsync_async(struct nfs_context *nfs, struct nfsfh *nfsfh, nfs_cb cb, voi if (data == NULL) { rpc_set_error(nfs->rpc, "out of memory: failed to allocate nfs_cb_data structure"); printf("failed to allocate memory for nfs cb data\n"); - free_nfs_cb_data(data); return -1; } bzero(data, sizeof(struct nfs_cb_data)); @@ -1077,7 +1198,6 @@ int nfs_ftruncate_async(struct nfs_context *nfs, struct nfsfh *nfsfh, off_t leng if (data == NULL) { rpc_set_error(nfs->rpc, "out of memory: failed to allocate nfs_cb_data structure"); printf("failed to allocate memory for nfs cb data\n"); - free_nfs_cb_data(data); return -1; } bzero(data, sizeof(struct nfs_cb_data));