From d88cabfd9abcd01c7729e5383919357da732ada9 Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Thu, 28 Mar 2024 19:17:10 -0600 Subject: nfp: Avoid -Wflex-array-member-not-at-end warnings -Wflex-array-member-not-at-end is coming in GCC-14, and we are getting ready to enable it globally. There is currently an object (`tl`), at the beginning of multiple structures, that contains a flexible structure (`struct nfp_dump_tl`), for example: struct nfp_dumpspec_csr { struct nfp_dump_tl tl; ... __be32 register_width; /* in bits */ }; So, in order to avoid ending up with flexible-array members in the middle of multiple other structs, we use the `struct_group_tagged()` helper to separate the flexible array from the rest of the members in the flexible structure: struct nfp_dump_tl { struct_group_tagged(nfp_dump_tl_hdr, hdr, ... the rest of members ); char data[]; }; With the change described above, we now declare objects of the type of the tagged struct, in this case `struct nfp_dump_tl_hdr`, without embedding flexible arrays in the middle of another struct: struct nfp_dumpspec_csr { struct nfp_dump_tl_hdr tl; ... __be32 register_width; /* in bits */ }; Also, use `container_of()` whenever we need to retrieve a pointer to the flexible structure, through which we can access the flexible array if needed. So, with these changes, fix 33 of the following warnings: drivers/net/ethernet/netronome/nfp/nfp_net_debugdump.c:58:28: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] drivers/net/ethernet/netronome/nfp/nfp_net_debugdump.c:64:28: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] drivers/net/ethernet/netronome/nfp/nfp_net_debugdump.c:70:28: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] drivers/net/ethernet/netronome/nfp/nfp_net_debugdump.c:78:28: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] drivers/net/ethernet/netronome/nfp/nfp_net_debugdump.c:87:28: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] drivers/net/ethernet/netronome/nfp/nfp_net_debugdump.c:92:28: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] Link: https://github.com/KSPP/linux/issues/202 Signed-off-by: Gustavo A. R. Silva Link: https://lore.kernel.org/r/ZgYWlkxdrrieDYIu@neat Signed-off-by: Jakub Kicinski --- .../net/ethernet/netronome/nfp/nfp_net_debugdump.c | 41 +++++++++++++--------- 1 file changed, 25 insertions(+), 16 deletions(-) (limited to 'drivers/net/ethernet/netronome') diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_debugdump.c b/drivers/net/ethernet/netronome/nfp/nfp_net_debugdump.c index a614df095b08..2dd37557185e 100644 --- a/drivers/net/ethernet/netronome/nfp/nfp_net_debugdump.c +++ b/drivers/net/ethernet/netronome/nfp/nfp_net_debugdump.c @@ -34,8 +34,11 @@ enum nfp_dumpspec_type { /* generic type plus length */ struct nfp_dump_tl { - __be32 type; - __be32 length; /* chunk length to follow, aligned to 8 bytes */ + /* New members must be added within the struct_group() macro below. */ + struct_group_tagged(nfp_dump_tl_hdr, hdr, + __be32 type; + __be32 length; /* chunk length to follow, aligned to 8 bytes */ + ); char data[]; }; @@ -55,19 +58,19 @@ struct nfp_dump_common_cpp { /* CSR dumpables */ struct nfp_dumpspec_csr { - struct nfp_dump_tl tl; + struct nfp_dump_tl_hdr tl; struct nfp_dump_common_cpp cpp; __be32 register_width; /* in bits */ }; struct nfp_dumpspec_rtsym { - struct nfp_dump_tl tl; + struct nfp_dump_tl_hdr tl; char rtsym[]; }; /* header for register dumpable */ struct nfp_dump_csr { - struct nfp_dump_tl tl; + struct nfp_dump_tl_hdr tl; struct nfp_dump_common_cpp cpp; __be32 register_width; /* in bits */ __be32 error; /* error code encountered while reading */ @@ -75,7 +78,7 @@ struct nfp_dump_csr { }; struct nfp_dump_rtsym { - struct nfp_dump_tl tl; + struct nfp_dump_tl_hdr tl; struct nfp_dump_common_cpp cpp; __be32 error; /* error code encountered while reading */ u8 padded_name_length; /* pad so data starts at 8 byte boundary */ @@ -84,12 +87,12 @@ struct nfp_dump_rtsym { }; struct nfp_dump_prolog { - struct nfp_dump_tl tl; + struct nfp_dump_tl_hdr tl; __be32 dump_level; }; struct nfp_dump_error { - struct nfp_dump_tl tl; + struct nfp_dump_tl_hdr tl; __be32 error; char padding[4]; char spec[]; @@ -449,6 +452,8 @@ static int nfp_dump_csr_range(struct nfp_pf *pf, struct nfp_dumpspec_csr *spec_csr, struct nfp_dump_state *dump) { + struct nfp_dump_tl *spec_csr_tl = + container_of(&spec_csr->tl, struct nfp_dump_tl, hdr); struct nfp_dump_csr *dump_header = dump->p; u32 reg_sz, header_size, total_size; u32 cpp_rd_addr, max_rd_addr; @@ -458,7 +463,7 @@ nfp_dump_csr_range(struct nfp_pf *pf, struct nfp_dumpspec_csr *spec_csr, int err; if (!nfp_csr_spec_valid(spec_csr)) - return nfp_dump_error_tlv(&spec_csr->tl, -EINVAL, dump); + return nfp_dump_error_tlv(spec_csr_tl, -EINVAL, dump); reg_sz = be32_to_cpu(spec_csr->register_width) / BITS_PER_BYTE; header_size = ALIGN8(sizeof(*dump_header)); @@ -466,7 +471,7 @@ nfp_dump_csr_range(struct nfp_pf *pf, struct nfp_dumpspec_csr *spec_csr, ALIGN8(be32_to_cpu(spec_csr->cpp.dump_length)); dest = dump->p + header_size; - err = nfp_add_tlv(be32_to_cpu(spec_csr->tl.type), total_size, dump); + err = nfp_add_tlv(be32_to_cpu(spec_csr_tl->type), total_size, dump); if (err) return err; @@ -552,6 +557,8 @@ nfp_dump_indirect_csr_range(struct nfp_pf *pf, struct nfp_dumpspec_csr *spec_csr, struct nfp_dump_state *dump) { + struct nfp_dump_tl *spec_csr_tl = + container_of(&spec_csr->tl, struct nfp_dump_tl, hdr); struct nfp_dump_csr *dump_header = dump->p; u32 reg_sz, header_size, total_size; u32 cpp_rd_addr, max_rd_addr; @@ -560,7 +567,7 @@ nfp_dump_indirect_csr_range(struct nfp_pf *pf, int err; if (!nfp_csr_spec_valid(spec_csr)) - return nfp_dump_error_tlv(&spec_csr->tl, -EINVAL, dump); + return nfp_dump_error_tlv(spec_csr_tl, -EINVAL, dump); reg_sz = be32_to_cpu(spec_csr->register_width) / BITS_PER_BYTE; header_size = ALIGN8(sizeof(*dump_header)); @@ -569,7 +576,7 @@ nfp_dump_indirect_csr_range(struct nfp_pf *pf, total_size = header_size + ALIGN8(reg_data_length); dest = dump->p + header_size; - err = nfp_add_tlv(be32_to_cpu(spec_csr->tl.type), total_size, dump); + err = nfp_add_tlv(be32_to_cpu(spec_csr_tl->type), total_size, dump); if (err) return err; @@ -597,6 +604,8 @@ static int nfp_dump_single_rtsym(struct nfp_pf *pf, struct nfp_dumpspec_rtsym *spec, struct nfp_dump_state *dump) { + struct nfp_dump_tl *spec_tl = + container_of(&spec->tl, struct nfp_dump_tl, hdr); struct nfp_dump_rtsym *dump_header = dump->p; struct nfp_dumpspec_cpp_isl_id cpp_params; struct nfp_rtsym_table *rtbl = pf->rtbl; @@ -607,14 +616,14 @@ nfp_dump_single_rtsym(struct nfp_pf *pf, struct nfp_dumpspec_rtsym *spec, void *dest; int err; - tl_len = be32_to_cpu(spec->tl.length); + tl_len = be32_to_cpu(spec_tl->length); key_len = strnlen(spec->rtsym, tl_len); if (key_len == tl_len) - return nfp_dump_error_tlv(&spec->tl, -EINVAL, dump); + return nfp_dump_error_tlv(spec_tl, -EINVAL, dump); sym = nfp_rtsym_lookup(rtbl, spec->rtsym); if (!sym) - return nfp_dump_error_tlv(&spec->tl, -ENOENT, dump); + return nfp_dump_error_tlv(spec_tl, -ENOENT, dump); sym_size = nfp_rtsym_size(sym); header_size = @@ -622,7 +631,7 @@ nfp_dump_single_rtsym(struct nfp_pf *pf, struct nfp_dumpspec_rtsym *spec, total_size = header_size + ALIGN8(sym_size); dest = dump->p + header_size; - err = nfp_add_tlv(be32_to_cpu(spec->tl.type), total_size, dump); + err = nfp_add_tlv(be32_to_cpu(spec_tl->type), total_size, dump); if (err) return err; -- cgit v1.2.3