| Message ID | 20230213084412.21065-8-jgross@suse.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Mini-OS: add minimal 9pfs support | expand |
Juergen Gross, le lun. 13 févr. 2023 09:44:12 +0100, a ecrit: > Add support to read from and write to a file handled by 9pfsfront. > > Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org> > --- > V2: > - add check for max message size > - return EAGAIN in case no free request got (Samuel Thibault) > - loop until all data read/written (Samuel Thibault) > V3: > - use an exact limit for read/write (Samuel Thibault) > - log read(write errors (Samuel Thibault) > --- > 9pfront.c | 216 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 216 insertions(+) > > diff --git a/9pfront.c b/9pfront.c > index fb2e5669..5da8a365 100644 > --- a/9pfront.c > +++ b/9pfront.c > @@ -72,7 +72,10 @@ struct file_9pfs { > #define P9_CMD_WALK 110 > #define P9_CMD_OPEN 112 > #define P9_CMD_CREATE 114 > +#define P9_CMD_READ 116 > +#define P9_CMD_WRITE 118 > #define P9_CMD_CLUNK 120 > +#define P9_CMD_STAT 124 > > /* P9 protocol open flags. */ > #define P9_OREAD 0 /* read */ > @@ -88,11 +91,39 @@ struct p9_header { > uint16_t tag; > } __attribute__((packed)); > > +struct p9_stat { > + uint16_t size; > + uint16_t type; > + uint32_t dev; > + uint8_t qid[P9_QID_SIZE]; > + uint32_t mode; > + uint32_t atime; > + uint32_t mtime; > + uint64_t length; > + char *name; > + char *uid; > + char *gid; > + char *muid; > + char *extension; > + uint32_t n_uid; > + uint32_t n_gid; > + uint32_t n_muid; > +}; > + > #define P9_VERSION "9P2000.u" > #define P9_ROOT_FID 0 > > static unsigned int ftype_9pfs; > > +static void free_stat(struct p9_stat *stat) > +{ > + free(stat->name); > + free(stat->uid); > + free(stat->gid); > + free(stat->muid); > + free(stat->extension); > +} > + > static unsigned int get_fid(struct dev_9pfs *dev) > { > unsigned int fid; > @@ -181,9 +212,12 @@ static void copy_from_ring(struct dev_9pfs *dev, void *data, unsigned int len) > * Only valid for sending. > * u: 2 byte unsigned integer (uint16_t) > * U: 4 byte unsigned integer (uint32_t) > + * L: 8 byte unsigned integer (uint64_t) > * S: String (2 byte length + <length> characters) > * in the rcv_9p() case the data for string is allocated (length omitted, > * string terminated by a NUL character) > + * D: Binary data (4 byte length + <length> bytes of data), requires a length > + * and a buffer pointer parameter. > * Q: A 13 byte "qid", consisting of 1 byte file type, 4 byte file version > * and 8 bytes unique file id. Only valid for receiving. > */ > @@ -192,10 +226,12 @@ static void send_9p(struct dev_9pfs *dev, struct req *req, const char *fmt, ...) > struct p9_header hdr; > va_list ap, aq; > const char *f; > + uint64_t longval; > uint32_t intval; > uint16_t shortval; > uint16_t len; > uint8_t byte; > + uint8_t *data; > char *strval; > > hdr.size = sizeof(hdr); > @@ -221,11 +257,21 @@ static void send_9p(struct dev_9pfs *dev, struct req *req, const char *fmt, ...) > hdr.size += 4; > intval = va_arg(aq, unsigned int); > break; > + case 'L': > + hdr.size += 8; > + longval = va_arg(aq, uint64_t); > + break; > case 'S': > hdr.size += 2; > strval = va_arg(aq, char *); > hdr.size += strlen(strval); > break; > + case 'D': > + hdr.size += 4; > + intval = va_arg(aq, unsigned int); > + hdr.size += intval; > + data = va_arg(aq, uint8_t *); > + break; > default: > printk("send_9p: unknown format character %c\n", *f); > break; > @@ -258,12 +304,22 @@ static void send_9p(struct dev_9pfs *dev, struct req *req, const char *fmt, ...) > intval = va_arg(ap, unsigned int); > copy_to_ring(dev, &intval, sizeof(intval)); > break; > + case 'L': > + longval = va_arg(ap, uint64_t); > + copy_to_ring(dev, &longval, sizeof(longval)); > + break; > case 'S': > strval = va_arg(ap, char *); > len = strlen(strval); > copy_to_ring(dev, &len, sizeof(len)); > copy_to_ring(dev, strval, len); > break; > + case 'D': > + intval = va_arg(ap, unsigned int); > + copy_to_ring(dev, &intval, sizeof(intval)); > + data = va_arg(ap, uint8_t *); > + copy_to_ring(dev, data, intval); > + break; > } > } > > @@ -348,6 +404,8 @@ static void rcv_9p_copy(struct dev_9pfs *dev, struct req *req, > uint32_t err; > uint16_t *shortval; > uint32_t *val; > + uint64_t *longval; > + uint8_t *data; > char **strval; > uint8_t *qval; > > @@ -412,6 +470,10 @@ static void rcv_9p_copy(struct dev_9pfs *dev, struct req *req, > val = va_arg(ap, uint32_t *); > copy_bufs(&buf1, &buf2, &len1, &len2, val, sizeof(*val)); > break; > + case 'L': > + longval = va_arg(ap, uint64_t *); > + copy_bufs(&buf1, &buf2, &len1, &len2, longval, sizeof(*longval)); > + break; > case 'S': > strval = va_arg(ap, char **); > copy_bufs(&buf1, &buf2, &len1, &len2, &len, sizeof(len)); > @@ -419,6 +481,12 @@ static void rcv_9p_copy(struct dev_9pfs *dev, struct req *req, > copy_bufs(&buf1, &buf2, &len1, &len2, *strval, len); > (*strval)[len] = 0; > break; > + case 'D': > + val = va_arg(ap, uint32_t *); > + data = va_arg(ap, uint8_t *); > + copy_bufs(&buf1, &buf2, &len1, &len2, val, sizeof(*val)); > + copy_bufs(&buf1, &buf2, &len1, &len2, data, *val); > + break; > case 'Q': > qval = va_arg(ap, uint8_t *); > copy_bufs(&buf1, &buf2, &len1, &len2, qval, P9_QID_SIZE); > @@ -640,6 +708,115 @@ static int p9_create(struct dev_9pfs *dev, uint32_t fid, char *path, > return ret; > } > > +static int p9_stat(struct dev_9pfs *dev, uint32_t fid, struct p9_stat *stat) > +{ > + struct req *req = get_free_req(dev); > + int ret; > + > + if ( !req ) > + return EAGAIN; > + > + memset(stat, 0, sizeof(*stat)); > + req->cmd = P9_CMD_STAT; > + send_9p(dev, req, "U", fid); > + rcv_9p(dev, req, "uuUQUUULSSSSSUUU", &stat->size, &stat->type, &stat->dev, > + stat->qid, &stat->mode, &stat->atime, &stat->mtime, &stat->length, > + &stat->name, &stat->uid, &stat->gid, &stat->muid, &stat->extension, > + &stat->n_uid, &stat->n_gid, &stat->n_muid); > + > + ret = req->result; > + > + put_free_req(dev, req); > + > + return ret; > +} > + > +static int p9_read(struct dev_9pfs *dev, uint32_t fid, uint64_t offset, > + uint8_t *data, uint32_t len) > +{ > + struct req *req = get_free_req(dev); > + int ret = 0; > + uint32_t count, count_max; > + > + if ( !req ) > + { > + errno = EAGAIN; > + return -1; > + } > + req->cmd = P9_CMD_READ; > + count_max = dev->msize_max - (sizeof(struct p9_header) + sizeof(uint32_t)); > + > + while ( len ) > + { > + count = len; > + if ( count > count_max ) > + count = count_max; > + > + send_9p(dev, req, "ULU", fid, offset, count); > + rcv_9p(dev, req, "D", &count, data); > + > + if ( !count ) > + break; > + if ( req->result ) > + { > + ret = -1; > + errno = EIO; > + printk("9pfs: read got error %d\n", req->result); > + break; > + } > + ret += count; > + offset += count; > + data += count; > + len -= count; > + } > + > + put_free_req(dev, req); > + > + return ret; > +} > + > +static int p9_write(struct dev_9pfs *dev, uint32_t fid, uint64_t offset, > + const uint8_t *data, uint32_t len) > +{ > + struct req *req = get_free_req(dev); > + int ret = 0; > + uint32_t count, count_max; > + > + if ( !req ) > + { > + errno = EAGAIN; > + return -1; > + } > + req->cmd = P9_CMD_WRITE; > + count_max = dev->msize_max - (sizeof(struct p9_header) + sizeof(uint32_t) + > + sizeof(uint64_t) + sizeof(uint32_t)); > + > + while ( len ) > + { > + count = len; > + if ( count > count_max ) > + count = count_max; > + > + send_9p(dev, req, "ULD", fid, offset, count, data); > + rcv_9p(dev, req, "U", &count); > + if ( req->result ) > + { > + ret = -1; > + errno = EIO; > + printk("9pfs: write got error %d\n", req->result); > + break; > + } > + ret += count; > + offset += count; > + data += count; > + len -= count; > + } > + > + put_free_req(dev, req); > + > + return ret; > +} > + > /* > * Walk from root <steps> levels with the levels listed in <*paths> as a > * sequence of names. Returns the number of steps not having been able to > @@ -731,6 +908,43 @@ static void intr_9pfs(evtchn_port_t port, struct pt_regs *regs, void *data) > wake_up(&dev->waitq); > } > > +static int read_9pfs(struct file *file, void *buf, size_t nbytes) > +{ > + struct file_9pfs *f9pfs = file->filedata; > + int ret; > + > + ret = p9_read(f9pfs->dev, f9pfs->fid, file->offset, buf, nbytes); > + if ( ret >= 0 ) > + file->offset += ret; > + > + return ret; > +} > + > +static int write_9pfs(struct file *file, const void *buf, size_t nbytes) > +{ > + struct file_9pfs *f9pfs = file->filedata; > + struct p9_stat stat; > + int ret; > + > + if ( f9pfs->append ) > + { > + ret = p9_stat(f9pfs->dev, f9pfs->fid, &stat); > + free_stat(&stat); > + if ( ret ) > + { > + errno = EIO; > + return -1; > + } > + file->offset = stat.length; > + } > + > + ret = p9_write(f9pfs->dev, f9pfs->fid, file->offset, buf, nbytes); > + if ( ret >= 0 ) > + file->offset += ret; > + > + return ret; > +} > + > static int close_9pfs(struct file *file) > { > struct file_9pfs *f9pfs = file->filedata; > @@ -1072,6 +1286,8 @@ void shutdown_9pfront(void *dev) > > static const struct file_ops ops_9pfs = { > .name = "9pfs", > + .read = read_9pfs, > + .write = write_9pfs, > .close = close_9pfs, > }; > > -- > 2.35.3 >
diff --git a/9pfront.c b/9pfront.c index fb2e5669..5da8a365 100644 --- a/9pfront.c +++ b/9pfront.c @@ -72,7 +72,10 @@ struct file_9pfs { #define P9_CMD_WALK 110 #define P9_CMD_OPEN 112 #define P9_CMD_CREATE 114 +#define P9_CMD_READ 116 +#define P9_CMD_WRITE 118 #define P9_CMD_CLUNK 120 +#define P9_CMD_STAT 124 /* P9 protocol open flags. */ #define P9_OREAD 0 /* read */ @@ -88,11 +91,39 @@ struct p9_header { uint16_t tag; } __attribute__((packed)); +struct p9_stat { + uint16_t size; + uint16_t type; + uint32_t dev; + uint8_t qid[P9_QID_SIZE]; + uint32_t mode; + uint32_t atime; + uint32_t mtime; + uint64_t length; + char *name; + char *uid; + char *gid; + char *muid; + char *extension; + uint32_t n_uid; + uint32_t n_gid; + uint32_t n_muid; +}; + #define P9_VERSION "9P2000.u" #define P9_ROOT_FID 0 static unsigned int ftype_9pfs; +static void free_stat(struct p9_stat *stat) +{ + free(stat->name); + free(stat->uid); + free(stat->gid); + free(stat->muid); + free(stat->extension); +} + static unsigned int get_fid(struct dev_9pfs *dev) { unsigned int fid; @@ -181,9 +212,12 @@ static void copy_from_ring(struct dev_9pfs *dev, void *data, unsigned int len) * Only valid for sending. * u: 2 byte unsigned integer (uint16_t) * U: 4 byte unsigned integer (uint32_t) + * L: 8 byte unsigned integer (uint64_t) * S: String (2 byte length + <length> characters) * in the rcv_9p() case the data for string is allocated (length omitted, * string terminated by a NUL character) + * D: Binary data (4 byte length + <length> bytes of data), requires a length + * and a buffer pointer parameter. * Q: A 13 byte "qid", consisting of 1 byte file type, 4 byte file version * and 8 bytes unique file id. Only valid for receiving. */ @@ -192,10 +226,12 @@ static void send_9p(struct dev_9pfs *dev, struct req *req, const char *fmt, ...) struct p9_header hdr; va_list ap, aq; const char *f; + uint64_t longval; uint32_t intval; uint16_t shortval; uint16_t len; uint8_t byte; + uint8_t *data; char *strval; hdr.size = sizeof(hdr); @@ -221,11 +257,21 @@ static void send_9p(struct dev_9pfs *dev, struct req *req, const char *fmt, ...) hdr.size += 4; intval = va_arg(aq, unsigned int); break; + case 'L': + hdr.size += 8; + longval = va_arg(aq, uint64_t); + break; case 'S': hdr.size += 2; strval = va_arg(aq, char *); hdr.size += strlen(strval); break; + case 'D': + hdr.size += 4; + intval = va_arg(aq, unsigned int); + hdr.size += intval; + data = va_arg(aq, uint8_t *); + break; default: printk("send_9p: unknown format character %c\n", *f); break; @@ -258,12 +304,22 @@ static void send_9p(struct dev_9pfs *dev, struct req *req, const char *fmt, ...) intval = va_arg(ap, unsigned int); copy_to_ring(dev, &intval, sizeof(intval)); break; + case 'L': + longval = va_arg(ap, uint64_t); + copy_to_ring(dev, &longval, sizeof(longval)); + break; case 'S': strval = va_arg(ap, char *); len = strlen(strval); copy_to_ring(dev, &len, sizeof(len)); copy_to_ring(dev, strval, len); break; + case 'D': + intval = va_arg(ap, unsigned int); + copy_to_ring(dev, &intval, sizeof(intval)); + data = va_arg(ap, uint8_t *); + copy_to_ring(dev, data, intval); + break; } } @@ -348,6 +404,8 @@ static void rcv_9p_copy(struct dev_9pfs *dev, struct req *req, uint32_t err; uint16_t *shortval; uint32_t *val; + uint64_t *longval; + uint8_t *data; char **strval; uint8_t *qval; @@ -412,6 +470,10 @@ static void rcv_9p_copy(struct dev_9pfs *dev, struct req *req, val = va_arg(ap, uint32_t *); copy_bufs(&buf1, &buf2, &len1, &len2, val, sizeof(*val)); break; + case 'L': + longval = va_arg(ap, uint64_t *); + copy_bufs(&buf1, &buf2, &len1, &len2, longval, sizeof(*longval)); + break; case 'S': strval = va_arg(ap, char **); copy_bufs(&buf1, &buf2, &len1, &len2, &len, sizeof(len)); @@ -419,6 +481,12 @@ static void rcv_9p_copy(struct dev_9pfs *dev, struct req *req, copy_bufs(&buf1, &buf2, &len1, &len2, *strval, len); (*strval)[len] = 0; break; + case 'D': + val = va_arg(ap, uint32_t *); + data = va_arg(ap, uint8_t *); + copy_bufs(&buf1, &buf2, &len1, &len2, val, sizeof(*val)); + copy_bufs(&buf1, &buf2, &len1, &len2, data, *val); + break; case 'Q': qval = va_arg(ap, uint8_t *); copy_bufs(&buf1, &buf2, &len1, &len2, qval, P9_QID_SIZE); @@ -640,6 +708,115 @@ static int p9_create(struct dev_9pfs *dev, uint32_t fid, char *path, return ret; } +static int p9_stat(struct dev_9pfs *dev, uint32_t fid, struct p9_stat *stat) +{ + struct req *req = get_free_req(dev); + int ret; + + if ( !req ) + return EAGAIN; + + memset(stat, 0, sizeof(*stat)); + req->cmd = P9_CMD_STAT; + send_9p(dev, req, "U", fid); + rcv_9p(dev, req, "uuUQUUULSSSSSUUU", &stat->size, &stat->type, &stat->dev, + stat->qid, &stat->mode, &stat->atime, &stat->mtime, &stat->length, + &stat->name, &stat->uid, &stat->gid, &stat->muid, &stat->extension, + &stat->n_uid, &stat->n_gid, &stat->n_muid); + + ret = req->result; + + put_free_req(dev, req); + + return ret; +} + +static int p9_read(struct dev_9pfs *dev, uint32_t fid, uint64_t offset, + uint8_t *data, uint32_t len) +{ + struct req *req = get_free_req(dev); + int ret = 0; + uint32_t count, count_max; + + if ( !req ) + { + errno = EAGAIN; + return -1; + } + req->cmd = P9_CMD_READ; + count_max = dev->msize_max - (sizeof(struct p9_header) + sizeof(uint32_t)); + + while ( len ) + { + count = len; + if ( count > count_max ) + count = count_max; + + send_9p(dev, req, "ULU", fid, offset, count); + rcv_9p(dev, req, "D", &count, data); + + if ( !count ) + break; + if ( req->result ) + { + ret = -1; + errno = EIO; + printk("9pfs: read got error %d\n", req->result); + break; + } + ret += count; + offset += count; + data += count; + len -= count; + } + + put_free_req(dev, req); + + return ret; +} + +static int p9_write(struct dev_9pfs *dev, uint32_t fid, uint64_t offset, + const uint8_t *data, uint32_t len) +{ + struct req *req = get_free_req(dev); + int ret = 0; + uint32_t count, count_max; + + if ( !req ) + { + errno = EAGAIN; + return -1; + } + req->cmd = P9_CMD_WRITE; + count_max = dev->msize_max - (sizeof(struct p9_header) + sizeof(uint32_t) + + sizeof(uint64_t) + sizeof(uint32_t)); + + while ( len ) + { + count = len; + if ( count > count_max ) + count = count_max; + + send_9p(dev, req, "ULD", fid, offset, count, data); + rcv_9p(dev, req, "U", &count); + if ( req->result ) + { + ret = -1; + errno = EIO; + printk("9pfs: write got error %d\n", req->result); + break; + } + ret += count; + offset += count; + data += count; + len -= count; + } + + put_free_req(dev, req); + + return ret; +} + /* * Walk from root <steps> levels with the levels listed in <*paths> as a * sequence of names. Returns the number of steps not having been able to @@ -731,6 +908,43 @@ static void intr_9pfs(evtchn_port_t port, struct pt_regs *regs, void *data) wake_up(&dev->waitq); } +static int read_9pfs(struct file *file, void *buf, size_t nbytes) +{ + struct file_9pfs *f9pfs = file->filedata; + int ret; + + ret = p9_read(f9pfs->dev, f9pfs->fid, file->offset, buf, nbytes); + if ( ret >= 0 ) + file->offset += ret; + + return ret; +} + +static int write_9pfs(struct file *file, const void *buf, size_t nbytes) +{ + struct file_9pfs *f9pfs = file->filedata; + struct p9_stat stat; + int ret; + + if ( f9pfs->append ) + { + ret = p9_stat(f9pfs->dev, f9pfs->fid, &stat); + free_stat(&stat); + if ( ret ) + { + errno = EIO; + return -1; + } + file->offset = stat.length; + } + + ret = p9_write(f9pfs->dev, f9pfs->fid, file->offset, buf, nbytes); + if ( ret >= 0 ) + file->offset += ret; + + return ret; +} + static int close_9pfs(struct file *file) { struct file_9pfs *f9pfs = file->filedata; @@ -1072,6 +1286,8 @@ void shutdown_9pfront(void *dev) static const struct file_ops ops_9pfs = { .name = "9pfs", + .read = read_9pfs, + .write = write_9pfs, .close = close_9pfs, };
Add support to read from and write to a file handled by 9pfsfront. Signed-off-by: Juergen Gross <jgross@suse.com> --- V2: - add check for max message size - return EAGAIN in case no free request got (Samuel Thibault) - loop until all data read/written (Samuel Thibault) V3: - use an exact limit for read/write (Samuel Thibault) - log read(write errors (Samuel Thibault) --- 9pfront.c | 216 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 216 insertions(+)